Breeding for Rust Resistance in Daylilies: 

Part 3

In this installment we look at realistic goals for our projects. Not everyone can or will have the same goals. What I outline here is my ideas concerning the goals that the entire daylily community might have overall or in the broader sense. However, each person's goals may vary, as their conditions and interest will vary. Some will have more ambitious goals, while others will have less ambitious goals, and that is ok. We can't all have the same goals, as we don't all have an equal situation or interest. There is no one goal that is 'right' while others are 'wrong'. I simply don't work from an 'either/or' proposition, but rather, from a 'both/and' position. It is up to each person to find the point that works for them. For my part, I believe we need a diversity of goals and interests, some working on the plant, others on the flower, some on both. In that way, we can push all the boundaries, and not just one or two. Please know that no matter what you decide you can or cannot do, I support you and appreciate your contribution to the vast and varied world of daylilies! Read on...

Being Realistic About Our Goals

Now that we have our terms defined, let us move on to consider what it means to be realistic about breeding for rust resistance. To begin with, from reading over many years of threads on various message boards and robins and speaking privately with many daylily breeders and growers, as well as general gardeners, master gardeners and landscapers, I see that there have been two equally unrealistic approaches to rust in the daylily world. The first I call the ‘ostrich syndrome’, which has been to ignore it, pretend it isn’t there, isn’t a big deal and won’t impact daylilies, and to either suffer through it and hope others don’t notice, not talk about it and attack anyone who does or just spray and pretend the problem is solved. The second is the opposite extreme, and is the ‘we must breed total resistance right now, at all costs’ approach. Both are too extreme and unrealistic to succeed and neither has succeeded.

On the one hand, rust has continued to spread, invading more and more gardens and moving further north each year and each year since rust appeared the word behind the scene is that daylily sales are diminishing and continue to diminish unabated, at least in the southern states (though clearly, recent economic uncertainty has contributed to this downturn in daylily sales, as has the aging and passing of many of the most committed collectors). On the other hand, many who began attempting to breed for total resistance (immunity) and nothing less have become disillusioned and stopped their pursuit of resistance breeding, either giving up entirely or throwing in the towel and getting in the ‘spray and ignore’ mode, because total resistance didn’t come about instantly. 

I believe that both approaches have been too extreme, ignoring the common middle ground where average breeders, hobbyists, gardeners and landscapers reside. Fear and uncertainty have certainly been a big part of this, but in addition to fear, I see a certain kind of laziness that manifests as a fear of the effort, as well as a lack of good information on realistically breeding for disease resistance that has caused a lot of uncertainty and only contributed to this situation.

There is much good information on breeding for disease resistance if one looks outside the daylily world. Many plant species have devoted breeders, professional/commercial breeders and/or hobby breeders, who have pursued various types of resistance in the breeding programs they have undertaken. Some have not succeeded, but many have succeeded well and should be studied and emulated. One of the most important things we can do is to get realistic about what our aims should be.

It should be obvious that I do not advocate a ‘total resistance’ or ‘absolute immunity’ approach, because I think this is highly unrealistic. The notion that we are only going to introduce plants that show immunity forgets that there is more than one strain of rust and rust will continue to mutate. In short, my aim would be to begin to focus on the production of plants showing good to high resistance through combining multiple genes for resistance, or conversely to make the removal of highly susceptible individuals a major goal of breeding, thus beginning to eliminate the introduction of more and more new rust magnets. Perhaps the most astonishing thing to me is that so many highly susceptible plants have been continually introduced since rust first reared its orange-speckled head in 2000. In my opinion, this reflects poorly on the daylily community (and is something I have heard echoed from daylily growers, master gardeners, home gardeners and landscapers alike, repeatedly).

So in practical terms, what am I actually suggesting the hobbyist do? Well, first of all, except for those few plants that show low tolerance or in those few areas of the country where rust is a continuous presence (and sometimes lethal problem), having some rust is not a great tragedy, especially where many of the plants you grow show good to high resistance and there is some effort made to reduce the presence of the least tolerant and/or most susceptible, so that the garden is still attractive and does not look like a disaster area.

It goes without saying that the first time rust shows up in your garden, you are in for a shock, because many things you grow may be highly susceptible. Sentimental favorites and expensive new introductions can quickly become hideous rust-fountains and may even show poor tolerance and be adversely effected for a whole growing season or more, but once the initial shock wears off, you can take a deep breath and start to note those that show minimal rust or even no rust. Then you can begin to research and communicate with others concerning cultivars that show good to high resistance or immunity. As you eliminate the most susceptible (or those with low tolerance are eliminated for you), you can then begin to divide and increase plantings of you own resistant plants and add new cultivars that show some resistance or immunity for other gardeners, knowing that results may be slightly variable in your garden, depending on the environment and the particular strain of rust you have as opposed to those that others have experienced.

It is a wise thing during this phase to focus on less expensive cultivars with a long track record of exposure to rust. Not buying large numbers of new introductions, unless some data about their rust resistance is available, would also be a wise approach. Or if you simply can’t part with some sentimental favorite or new expensive introduction or must have something that is unknown, spraying may be a viable option for you and information about sprays is readily available online.

Do note though that spraying is expensive and only masks the problem, so I do not feel it is actually a viable approach for breeders, but at least you won’t see rust. If you are selling plants, it will probably be necessary for you to spray, but that does not mean you have to spray year round. If you spray in spring, but then stop spraying in late summer, you can still rate cultivars and especially any seedlings you may raise for their rust response. I personally consider this the most responsible spraying regimen for sellers, as it allows some awareness and culling for rust susceptibility. It must be noted though, that no one who is spraying in order to sell is actually verifiably ‘rust free’, because spraying does not kill rust in the plant, but only suppresses the sporation, thus any plant purchased from a ‘rust free garden with a spraying program’ can sporate once they are in their new home and no spray is being applied, if there was any exposure in that sell-garden in the past. This happens frequently and is one of the major ways that rust is spread. Spraying is only a prophylactic, not a cure!

So once you are past the initial shock of your first rust outbreak, and all the heartbreak has ensued, tears have been shed, curses have been uttered and hair has been pulled, you may begin to find that once the most susceptible are gone, rust is not too unbearable in a garden setting. This has been my experience and has helped me to see the middle ground approach I am advocating here. A garden full of rust-fountains is traumatic, but a garden full of plants with some slight amount of rust and some plants with no rust at all is quite manageable and not too terribly noticeable. 

I manage a garden where this is the approach we have taken and now our annual fall outbreak is barely even noticeable unless you go out and start actively looking on the undersides of the leaves. So how was this accomplished? By removing the highly susceptible altogether and only keeping or adding those with high resistance and/or immunity, most notably by dividing those of that nature in the garden and increasing the plantings of those cultivars and by then judiciously and slowly adding new cultivars that have been shown to have some resistance and then removing any of those that failed and increasing those that have shown suitable resistance in that garden. 

I consider this approach to simply be an aspect of garden maintenance and building. With experience, you too will come to realize that not everything you plant succeeds and some things fail and must be redone, replanted, rethought. This is life in the real world. However, this garden is not a breeding garden and in such I would take a different approach, but I think the approach I have taken in this garden is a realistic approach for the average gardener.

The major difference in a breeding garden would be that I would leave a good number of the most rust susceptible in order to be sure the seedlings and potential breeders were sufficiently exposed to rust to confirm their resistance levels. The cultivars that I would personally tend to keep to ensure proper rust exposure also would tend to be those I would be most interested in using for ‘salvage projects’, so such cultivars in my hybridizing garden serve two purposes – to infect the future generations and to preserve a special trait for later blending into resistant lines.

Since a small amount of rust in a garden is neither unsightly nor deeply traumatizing (to the gardener or the plants) and since the goal of breeding for total immunity is highly unrealistic for the average breeder, I tend to find that breeding for good to high resistance is the most realistic approach, with immunity both welcome and sought after, but not the only goal of the breeder. To make full immunity the sole goal of a breeding project is to invite failure and disillusionment, both of which usually lead to giving up, but when the focus is both plants with usable resistance and the removal (or non-introduction) of those with high susceptibility, we can see progress and be encouraged enough to continue our work. This is a realistic goal that is achievable and will lead to plants that can be useful and valuable to gardeners, landscapers, breeders and collectors. Further, it serves the purpose of eliminating new rust magnets, which are so disheartening and angering to so many, now that rust is simply a reality of growing daylilies.

The old rust magnets from the pre-rust days may be excusable because they were introduced before rust appeared, but the same cannot be said for those introductions made since rust appeared, especially those from recent years. I would strongly encourage the identification of resistant cultivars and the introduction of new cultivars showing resistance to help the daylily maintain its place amongst the gardens of the world and not continue to slide further and further out of favor. For the average gardener, plants showing acceptable resistance are going to become more and more important if they are to continue to grow daylilies.

I would stress that I do not advocate a rush to compost every rust magnet, or highly susceptible cultivar. There are reasons for this. The first and foremost is that one of those that is highly susceptible to a current form of rust may have resistance to a new form of rust that may emerge, or there may be other important genes there. I do think that identifying those with high susceptibility is important both to allow gardeners to avoid them and to allow those who wish to maintain them to know what they are getting into. In that vein, I do encourage that those who are going to spray anyhow to maintain as many of these as they can, just to keep the gene pool present, but I would encourage them to note their susceptibility to prospective buyers and perhaps use them with great care in breeding projects, possibly only in a salvage project wherein the offspring will be exposed to rust and culled for susceptibility.

I do not advocate the destruction of huge swaths of the domestic daylily gene pool, and I do not think a breeder should rush in and destroy all their seedlings from a given cultivar, just because it is highly susceptible. Rather, watch those seedlings carefully and look for any improvement in resistance over the susceptible parent and use them to continue the salvage project. A salvage project of this nature can take generations to achieve, after all. 

There will be a difference in what is maintained by a collector who is spraying their garden, by a breeder who is responsibly trying to continue improving the entire daylily and the average gardener or landscaper who wishes to grow daylilies. The first of these may wish to spray, the second may even spray for part of the year, but the last two aren’t likely going to spray and until we acknowledge this fact and begin to think of their interests, we condemn our beloved plant to a future of obscurity and infamy amongst such people, especially in warmer areas. Ask yourself this – How many average gardeners or landscapers use tea roses?

Now some may come along and say, “But what will you do when a new strain of rust comes your way? Then all your work will be for nothing!” Well, not necessarily. To begin with, we do not know how much variation of effect there may be in the various strains of rust. Secondly, we do not know how much variability of response there may already be in resistance genes in the current daylily gene pool, and just as new strains of daylily rust will appear, so too will new mutations for resistance appear (or be recognized as already present) in the daylily. This is a genetic dance after all between pathogen and host. 

Further, my personal approach to various strains of rust will be to simply note how a given cultivar showing high resistance over many years responds to a new strain that it has susceptibility to and then to cross it to a cultivar that shows good resistance to that strain. Thereby I can combine genes for resistance to various strains of rust. In other words, as rust continues to mutate, my work continues, so there is never a point at which one is ‘done’ and has developed ‘proven lines of daylilies that can never get rust’. In reality, there is no such thing, so rust resistance becomes just another trait that the breeder is observing, recording information about and selecting for, just as any other trait such as branching, foliage type, sun-fastness, water resistance of flowers (non-water-spotting), etc. In the end, time and time again, we see that most breeders can walk and chew gum at the same time…I believe selection for rust resistance is just another aspect of selection and nothing more.

To end this section, let us reiterate the practical methods of dealing with rust for various settings.

1. For average gardeners and landscapers, identification and use of good to highly resistant or immune cultivars is paramount, as is removal of highly susceptible cultivars and replacement with another species or another cultivar of daylily known to show resistance or immunity. In this way, the garden is kept attractive and expensive spraying programs are avoided. Production of resistant, garden-worthy daylily cultivars then becomes paramount for breeders, as well as education and identification of resistant cultivars amongst collectors and sellers, in order to maintain the interest in daylilies of this segment of the gardening population.

2. Collectors and sellers use a spraying program if desired or legally required, at least through their sell/display season. They maintain both resistant and no-resistant stocks, but make some effort to know which is which, at least marginally. No more ‘ostrich syndrome’ as if it is irrelevant or they can’t be bothered with such trivialities. Become part of the solution, rather than part of the problem. Sellers should be able to advise prospective clients on those cultivars showing some resistance to attempt to ensure happy customers and to not further damage the reputation of the daylily in the eyes of people becoming increasingly wary.

3. Breeders begin to identify cultivars showing good to high resistance and/or immunity and use those cultivars. Breeders maintain a suitable number of susceptible individuals to assure rust infection of their seedlings and where they must use their highly susceptible cultivars and seedlings in their breeding work, make them part of a salvage program to bring desired traits onto a resistant plant by crossing them to known resistant and/or immune plants. The goal of the breeder is not to create total immunity, but acceptable resistance, with the presence of occasional immune individuals as an added bonus, while also eliminating (and not introducing) the highly susceptible. Breeders seek out, identify and use resistant cultivars and expose (at least) their seedlings to rust in order to eliminate the most susceptible. 

Elimination of the most susceptible individuals becomes the most important aspect of breeding programs. The more of these that can be eliminated as future breeders or introductions, the better it is for the potential resistance of your overall gene pool. In other words, exposing your seedlings and eliminating the highly susceptible becomes the most important aspect of breeding for resistance along with using cultivars and seedlings that have shown consistent resistance over a long period of time and in multiple locations. We will look at these points in much greater detail when we discuss breeding strategies.

For our next installment, we will consider the importance of identifying consistently resistant cultivars...

Breeding For Rust Resistance In Daylilies:

Part 2

In this installment, I want to focus on some basic definitions that we absolutely must have some understanding of before we can proceed further. I frequently see discussion on various forums that don't get anywhere and often because people are using the same words, but meaning different things. The greatest fallacy is that 'resistant/resistance' implies fully immunity to rust. This is not the case, as I discuss below, but the notion that this is the case seems to be one of the biggest stumbling blocks to understanding and communication.

Resistance, Immunity, Susceptibility and Tolerance

Before we begin to talk about various strategies for breeding for resistance, there are a few terms we need to define and discuss a bit. As this sections header suggests, resistance and immunity are not the same thing, and while resistance and susceptibility can encompass various points of a spectrum, they are neither the same as tolerance. So what do I mean when I use any of these terms.

First, let us consider immunity. This is the simplest of the terms to define, as immunity means exactly what it implies. An individual that shows immunity to a pathogen is not able to be infected by or show symptoms of infection of a given pathogen. In terms of rust, this means that a cultivar that is immune or that shows immunity does not display any symptoms of rust to the naked eye. Under a microscope or in lab conditions, rust may be found to be present, but such an individual will not show the visible effects of rust – spores or active, visible rust.

Some individual plants may show immunity due to environmental reasons, but others may be due to an actual gene or genes giving full immunity to rust. This is likely rare. More rare would be complete immunity to multiple strains of rust, so while cultivar may prove to be immune to one strain of rust, it may not be immune to another, and the level of susceptibility to any given strain could vary, even in the individual plant is highly immune to one or two strains of rust. While full immunity to multiple strains of rust is likely very rare, if it even exists, there is always the chance that it could exist. Without gathering information on individual clones over many locations and many years, the discovery of such a multi-immune plant will be very difficult.

In many plants and animals, total immunity is often a single, dominant gene expression and is frequently more easily circumvented by new mutations of the pathogen than multigenic resistance. However, if a single dominant gene that confers immunity (or high resistance) is combined with multiple other genes giving resistance in various levels, that can create a very strong level of immunity/resistance that can be both difficult for a pathogen to breach and offer some resistance to multiple strains of a given pathogen. Thus these single gene dominants should not be ignored and make an important component of a resistance-breeding program.

Now let us consider resistance and susceptibility together, as they go hand-in-hand and are actually interchangeable terms. First, resistance is not immunity. I can’t stress this enough. The only time that resistance is immunity is if we were to refer to ‘total resistance’ or ‘complete resistance’. However, more frequently, resistance is aimed more at meaning the ability to resist a pathogen to some extent, variable by cultivar or clone, though certainly in the hobby, the term resistance is often used to mean immunity by some, but then will be used to infer variable levels of resistance, but not immunity by others. This has caused a great deal of confusion and when the term resistance is used to imply immunity or the meaning is left vague, it can leave people both intimidated as to the difficulty of achieving such a goal and disheartened when a “resistant” cultivar then shows some rust in their garden. We need to be very clear about what we are actually meaning when we use a given term.

When dealing with multigenic, quantitative traits, we generally use a bell curve to express the array of phenotype expressions seen. So the two extreme points of any bell curve could be strong resistance/poor resistance with many shadings in between, or equally, the two extremes could be called low susceptibility/high susceptibility and be equally accurate. Said either way, they basically are saying the same thing. However, I have heard those who don’t want to acknowledge the importance of highly resistant plants to the actuality of there being genetic resistance that is selectable within the Hemerocallis suggest that because the two terms are interchangeable, that means that all daylilies get rust and even if you have one that is highly resistant and you see a few spores on it, then you still have rust, so it is really no better than the most susceptible rust magnet. This is complete nonsense, of course and is usually being stated by persons selling or breeding and selling daylilies. Any grower who has ever experienced rust knows that the visual effect, as well as the effect on the health of the plants, is profoundly different between a cultivar that gets a few rust spores and one that is such a magnet as to become an orange rust-fountain. We will discuss this more a little later in this section when we look at realistic goals for our breeding projects. Suffice to say for now that ‘resistance’ and ‘susceptibility’ is interchangeable terms that describe a wide range of expressions, but not necessarily immunity.

Tolerance is a somewhat different term that means the ability to be infected by a pathogen, express the pathogen, and yet show little negative impact on health, vigor or performance. In short for our example, it is the ability of a plant to have rust, show sporation and yet have little negative impact on the performance and/or health of the given plant, even in some instances when the rust expression is extreme (low resistance or high susceptibility). This is also an important point in breeding consideration and one that is often overlooked. There are plants that will contract rust and show strong negative effects either the year that rust is present and/or in the next growing season, even if the rust is eradicated by winter freezes or spraying. These plants may show symptoms such as reduced scapes count and/or height, poor bud count, poor branching, poor plant habits, reduced increase or fan-count, or even withering of the overall plant size along with several of the other expressions mentioned here. In extreme cases, some plants are so compromised by rust that they never fully recover or perform at full capacity again, and in areas where rust is seen in both spring and fall, such plants may become so compromised that they die outright, even if their other cultural needs are being met.

In our breeder selection and breeding consideration, especially where we want to pursue a ‘salvage project’ with a very susceptible plant, we may make better strides by using a highly susceptible plant that shows high tolerance to the presence of rust, rather than one that is highly compromised by rust infection. Then, at the very least, even if we do not make great strides toward high resistance in the first generation, our f1 should at least flourish and survive to make an F2 or BC1 (back cross first generation) and perhaps then draw together the flower traits we want with higher resistance. In short, tolerance to rust can’t hurt and likely will help, but low tolerance to rust can be deadly and certainly creates more obstacles to overcome.

Breeding for Rust Resistance in Daylilies - Part 1

Breeding for Rust Resistance in Daylilies:

Part 1

This is the first part in a series of blog posts that are actually one document I have been working on for the last couple of years. It is simply far too long, with far too many topics and too much information to be made into one post. For our first installment, I wanted to give a short overview of my background and experience and then introduce one simple concept - the difference between hobby breeding and professional research breeding. The first few posts will deal with concepts. Then we will move on to actual breeding methods in the later posts. It is important to get our concepts and definitions under out belt before we get into any complicated breeding strategies.

With that said, one of my goals with this series of posts is to make this information accessible to hobbyists. I will at times use the language of science, but I will also go out of my way to either offer examples or use more common language that the average hobbyist can relate to. The goal of this series is to demystify 'resistance breeding' and to help you, the hobbyist breeder, to see that breeding for some level of rust resistance is not some magical endeavor beyond the scope of the average backyard breeder, and that it is actually possible to approach selection for rust (or any other pathogen) just in the manner you currently approach any other trait you select for.

You don't have to have a PhD, a laboratory or many acres of grow-out fields to make some progress in selecting for resistance, any more than you have to have those things to make progress selecting for better branching, cool morning opening, dormant foliage or any of the many other traits you already select for. 

Introduction and Bio

First, I would like to present some of my background for those who do not know me and are not familiar with my work in selection and breeding for disease resistance over the last two decades.

It is important to state first and foremost that I am not a professional genetic researcher affiliated with any university or industry. I am an independent researcher and breeder, but I have worked with several professional researchers over the last two decades in my research and the practical application of my findings through breeding and selection.

My road to working with immuno-genetics (the study of genetic, heritable disease resistance) started early due to the fact that every group of animals or plants I worked with from childhood on was beset by some plague or another. For many years, through my childhood and into my early twenties, I followed the standard prescription of ‘medicate, and then medicate some more’. Over time though, I came to realize that this was no answer, only a prophylactic to keep the problem invisible.

In the early nineteen-nineties I began breeding rare chickens to study their feather color and patterning genes as well as their feathering and form genes. However, the most immediate issue became clear very quickly: chronic disease. At first I considered inbreeding to be the source of the suppressed immune systems, but even in very wide outcrosses, the problems persisted. Then I had blood work done and found the causative pathogens. Medications were prescribed, but they did nothing more than mask the problems and as soon as the treatment was withdrawn, the problems returned within 7-10 days.

So that set me on a path of research to understand how people in the pre-medication past dealt with such problems, what the poultry research community had learned about genes that impart resistance to given pathogens and how to practically apply that information to a breeding program to produce lines of genetically resistant birds. To spare the reader and daylily enthusiast the pain of reading many pages of details about breeding for chicken disease resistance, I will simply state that through combining multiple genes for resistance, I have been able to create lines that are fully immune for two major pathogens: Mycoplasma gallisepticum and the Marek’s Virus complex.

Practical Breeding versus Scientific Research

I want to state for the record that there is a difference between what we do as breeders and the research and experimentation we may pursue, and the research that is done by scientists in university or industry settings. It is so important to emphasize that they are not the same thing. I have done both types of ‘research’ and I know that they are both useful and have their place. I want to stress the difference in these two approaches, because I do not want any of the real professional researchers who may read this to assume that I don’t know the difference, or that I am leading any lay-persons reading this to believe that one is the equivalent of the other.

Professional research is designed to obtain factual, quantifiable, replicable proof of a given issue. Breeding research and experimentation is to allow the breeder to make advances in their chosen goals and intelligent choices in their own breeding programs, to gain the desired results. Professional research is important, but it often does not translate well to the hobbyist breeder and may even be relatively useless for practical application by hobbyist breeders. Conversely, hobbyist research and experimentation is aimed toward achieving desired results, and often has little value to the professional researcher because it does not follow the strict controls of real scientific research programs and generally the hobbyist is not working with the numbers required to acquire sufficient data to make claims of proof. Our results in the hobby tend toward being evidence of a particular pattern of heritability, but are generally not proof as the professionals mean the term, and it is important to recognize this up front. This, of course, is generally of little concern to the hobbyist breeder who only wants to be able to replicate desired results with some accuracy.

With that said though, I will state that while the professionals are seeking quantifiable, replicable proof, the breeder is generally only seeking indications of trends that can help them achieve their desired results. For instance, professionals will often criticize hobbyist breeders for making claims such as ‘so-and-so shows resistance or immunity, recessiveness or dominance, single gene or quantitative effects, etc’, because to the professional researcher, such a claim could only be made after sufficient numbers had been observed under strict protocols to prove such a statement in a quantifiable, replicable manner. However, the breeder really doesn’t need that kind of proof to pursue a breeding program. The breeder only wants to see trends that appear to fit such patterns of inheritance so that he or she can have some idea of how to pursue a breeding program to obtain the desired results.

For instance, Dr. Stout had no proof, in the current scientific sense, that a red daylily could be created. Yet, he spent twenty years pursuing the goal and created ‘THERON’, the first red daylily hybrid, as a result. Further, no scientific research project was initiated to prove that toothed, wildly ruffled or pie-crusted edges could be bred onto daylilies. Instead, breeders simply pursued the goal of such edges based on the presence of very minute examples of such edges. Through breeding such individual cultivars together, selecting for the highest expression of the trait and continually concentrating the target trait, such edges became a reality. We can see the results of that effort and selection process today. The presence of such edges in many modern daylily cultivars is proof, after the fact, that such edges are possible, but there was no proof at the beginning, only the suggestion that such was possible. These are only two of many examples of such breeding and selection in the many cultivars of hybrid daylilies that we know today, and many more examples exist in all domestically bred plants and animals.

This is the big difference between professional researchers and hobbyist breeders and researchers. The professionals are seeking proof, while the breeder is seeking results. The professional is seeking quantifiable, replicable proof through their research that can then be peer-reviewed (which is often a rather savage process), while the hobbyist breeder is seeking trends and results through their research and experimentation. That does not mean that the research and experimentation of hobbyists cannot be pursued in a scientific manner, using sound scientific principals. It simply means that hobbyist research is not of the standard to constitute proof in the modern, scientifically accepted sense. It does though, often, produce results. Both types of research, experimentation and breeding have their place, but they are not the same thing and it is important to be aware of that and to acknowledge the difference.

Using Stress as a Selection Tool

Using Stress as a Selection Tool

In breeding any plant or animal, we often have the tendency to pamper our precious offspring, especially if we only have a few or they come from expensive and rare parents. There are instances where this may be warranted, but they are few and far between. If we are talking about a very rare parent or narrow gene pool, or if we only have a few offspring, we may pamper those few in order to get them to reproductive age and increase the rare stock. In time though, as numbers increase, our goals should shift toward selecting for the most vigorous and hardy individuals within the gene pool to continue increasing the numbers of that particular family line. In the vast majority of instances though, pampering does not help the family line nor is it helpful in gene pools that have large numbers of individuals. In fact, in those instances, it can be detrimental.

In breeding, we usually understand that the things we actively select become concentrated into our gene pools, but we often fail to realize that those things we ignore and do not actively select can become imbedded in our gene pools just as easily. I refer to this as passive selection, in order to contrast it to active selection. In active selection, we actively select for certain traits, generally seeking to increase them. With passive selection, we are not actively selecting for a trait or traits, but we accidentally select those traits through ignoring them or not creating conditions that reveal them.

An excellent example of this is crown rot. We know there is some genetic aspect involved with this deleterious trait, as crown rot is prominent in particular family lines. So when we use those family lines, we run the risk of creating more cultivars with the propensity for crown rot. In order to select against the crown rot trait, we would want to expose seedlings to the conditions that are conducive to crown rot, in order to select those seedlings for further evaluation that do not show the trait and then to also eliminate those seedlings that do show crown rot. 

I have found two techniques to test against crown rot. One is to grow seedlings in fairly moist conditions and the other is to divide and replant seedlings in hot, moist conditions. By doing these things you can identify those that have a high propensity to crown rot and eliminate them (if they don't actually eliminate themselves for you). 

This picture shows some of my seedling growing tubs. Note that the drainage holes are drilled 1/3rd of the way up on the sides, rather than on the bottom of the containers. This is done for two reasons, both involving the creation of a water reservoir. The first reason is that this reservoir ensures there is water retained there so that in very dry weather, supplemental watering is not necessary on a constant basis. The second is that in wet weather, and through much of the winter, the seedlings are kept constantly moist. In hot, wet weather this will activate rot in those families that are susceptible, while families that are not susceptible show no crown rot. This added water stress can eliminate rotters, but in those individuals that have no susceptibility, it actually increases the rate of growth, thus serving two purposes.

However, I frequently hear people talk about how they only move their seedlings late in the year when it is cool to "avoid rot". This is a way to avoid seeing rot, but by not seeing rot, you can not make selection against the trait. You are then passively selecting toward the propensity to rot because you are not actively selecting against it. There is always the chance that the seedlings you select for further breeding or introduction won't carry the rot trait, but there is just as high a chance that you will select the worst rotters and if you don't provide the conditions to reveal those traits, how will you know?

Rust is another excellent example. There are genes for resistance to rust in daylilies, but a great many breeders spray to suppress rust from going into the spore phase throughout the year so there is no way they can be selecting for those individual seedlings that show higher levels of resistance or immunity to rust.

In both instances, the breeders undoubtedly feel they are doing the right thing and taking the best possible care of their plants, but the "best possible care" of the individual plants is not always the best possible situation to select the best possible plants in the next generation, though it might allow you to select "the best" flowers, if that is your only focus. In short, the best interest of the entire gene pool is not always the same as the best interest of the individual plant.

In breeding it is very important to remember this. If we pamper our plants those individuals may flourish, but we may thus be compromising our gene pool by not having proper situations by which to select for important traits such as plant vigor or disease resistance. The only way we can really select for such traits is by creating (or allowing) the conditions that reveal the plants with the best concentration of genes for the desired traits.

So let's take a minute to think about some of these (rather obvious) points.

1. If you are concerned about drought tolerance, don't water your seedlings (and maybe your breeders too).
2. If you are concerned about disease resistance, expose your seedlings and breeders to the diseases that concern you and the conditions that accelerate the disease(s).
3. If you are concerned about flowers opening on cold mornings, grow your seedlings on the Northern side of your house or garden, or in a cold-pocket microclimate.
4. If you are concerned about water spotting, then overhead water when scapes are flowering.

While this area of my hybridizing garden may look lush, it is in fact very dry. A south facing slope, the soil is a mixture of sand and orange clay with a very thin layer of topsoil. I use this particular area to test out potential breeders and seedlings for drought tolerance. This area is too far away from the hose for convenient watering and I am highly unlikely to actually carry buckets of water very far. In the drought of 2012, I was able to produce over 7,000 seeds from this area because the cultivars I focused on there have proven themselves fertile in full sun and dry conditions over several years. Not surprisingly, the seedlings from those cultivars tend to also set seeds well in full sun and dry conditions...

These are just a few ideas. There are many, many more examples. Think of the traits (faults) that you want to work against and then think about the conditions that seem to bring out or accelerate these negatives and how you might expose your plants to these conditions in order to reveal those with the weakness, as well as, and most importantly, those that do not display the weakness. Select the later to move forward with!

I was recently watching a Youtube video where Dan Heims of Terra Nova Nurseries speaks about how new perennials enter the market. It is fascinating and I recommend you watch it, but I was particularly excited by one comment he made in regards to breeding new plants. He states that he starts all breeding projects by asking the question, "What is wrong with this plant". He says that he is looking at the problems in order to solve them through selection. His story about breeding pulmonaria for mildew resistance is fascinating and every daylily breeder should take head to the successful techniques of this master breeder. Below is the link to the Youtube video of his talk. Enjoy! 

Dan Heims, Perennials from Around the World

Thoughts and Observations: Inbreeding

Thoughts and Observations:

Inbreeding

Brian Reeder

*I wanted to note at the beginning of this post that I am writing one post this month for the blog, which will also be used for my monthly article in the Bluegrass Hemerocallis Society newsletter as well as for Exhibition Poultry E-zine. This article is a general article on breeding techniques with a focus on inbreeding and is fairly equally applicable to animal breeding and plant breeding. I may use specific examples of a particular plant or animal, so if you want it to specifically apply to your plant or animal, just change the name in your head to what you are working with. The underlying principals are the same, with only one exception - you can't self-mate (most) animals as you can with many plants.

Breeding in many ways is as much an art as a science. Science (genetics especially) is always a valuable tool in the breeder’s toolbox, but I always like to point out that our ancestors created the vast majority of domestic plants and animals long before there was any knowledge of genes, beyond perhaps the most cursory understanding that "blood will tell". The art of breeding, like any art, has a lot to do with individual taste. What I may adore, you may despise and vice-versa, but in the end, we all use basically the same set of techniques to produce our desired outcomes. 

There are really only so many approaches to breeding that one can take - outcrossing, backcrossing, line breeding, inbreeding, etc. We all use these techniques to one extent or another. It is interesting to me that in some circles though, one or the other of these techniques have taken on a superstitious veneer of 'taboo' status. For instance, in ornamental plant breeding, we see a majority of outcrossing and little inbreeding (or at least little that is openly admitted), generally due to the old notion that inbreeding is "bad". In animals, we see little outcrossing (again that is openly admitted) but lots of inbreeding, due to the equally superstitious notions of "crossbred" and "mongrel" or "un-pure" as opposed to "purebred". Each set of suppositions limits the breeders in those respective arenas.

There are no good or bad breeding techniques. There are only breeding techniques, and in some instances, each is of great value while in other instances, any given technique can be disastrous. It really all depends on the individual situation and the desired outcome. Inbreeding particularly gets a really bad rap, and there are some very negative potentialities to inbreeding if it is not applied carefully.

Inbreeding is used to concentrate genetic traits. It is that simple, and inbreeding will concentrate whatever is there, good or bad. Inbreeding can be especially valuable in determining what recessive genes are lurking in a particular population. If there are bad genes, deleterious genes, hidden in a population you can bet that inbreeding will bring them to the surface, but there is also no better way to determine what bad genes are lurking in a particular population. On the other hand, there is no better technique than inbreeding to determine what good genes are lurking in a population. As well, inbreeding can reveal how extreme a given trait can become and if a trait that is neutral in lesser expression will become dysfunctional or deleterious in higher concentrations. 

I have used inbreeding a great deal in strain development both to concentrate desired traits and to reveal undesirable traits in both plants and animals. I always approach inbreeding with a very careful eye, quick to note when there are undesired traits and I am equally quick to eliminate a line or discontinue inbreeding when it becomes clear that there are many deleterious factors carried in a line. However, in some instances, inbreeding for generation may reveal no deleterious factors and in such instance, may only concentrate and strengthen the positive traits of the lineage.

In my work with daylilies, one of the first tests I like to run on a given cultivar is to self it. That is, breed it to itself. The first thing I am looking for is if the cultivar is self-fertile. The next thing I am looking for is how clone-like the seedlings of selfing may be, or how much variation they show. The former indicates a great deal of homozygosity and/or many dominant genes, while the later indicates heterozygosity of some or many genes. In the case of the former, I will then know that I may not be able to create anything very different from the parent in an F1 outcross, and so it becomes a producer of bridge plants for further breeding. If the plant is highly heterozygous for many traits, then one can expect to produce a wide range of phenotypes in the F1, and feasibly something different enough from the parent or unique enough to potentially be an introduction in its own right. However, I still consider such a cross more for the production of breeding material than for introductions, but that is my focus anyhow. For me, introductions are really the last thing on my mind with any cross at this time, while the production of new and improved breeding materials is always paramount in my efforts.

Chickens can't be selfed, but they can be crossed with full or half siblings and they can be backcrossed to either parent. To me, this is the only really tight inbreeding that is likely to reveal the hidden traits I wish to evaluate. The breeding of cousins, for instance, while inbreeding in the broadest sense, is to my way of thinking more in line with line breeding, and less pure inbreeding. While the purest inbreeding in plants is selfing, sib x sib matings as well as backcrossing to either parent (or aunt/uncle, grandparents) are useful techniques of inbreeding and can be equally as revealing for strengths or weaknesses as selfing. Backcrossing is particularly suited to revealing the hidden details of one or the other of the parent lines. The biggest pitfall with inbreeding comes when people get so tunnel-visioned on a particular trait that they ignore problem genes, sacrificing viability for phenotype extremes.

To put it more bluntly and in more common language, if you have bad traits in a line and you inbreed, you are likely to destroy that line as the bad traits become more and more concentrated. Conversely, if you have good traits, but no bad traits, inbreeding can concentrate those good traits and make them even more prominent. In reality, most lines have some of each, and so inbreeding must be approached cautiously and with care, being always aware to stop inbreeding when bad traits become glaringly obvious, no matter how "good" the line looks otherwise.

In animals, any given breed or line is likely to be the product of some inbreeding already. With animals, inbreeding can very quickly cause a lot of problems, and only the most vigorous and hardy lines are usually good subjects for intensive inbreeding. However, inbreeding is much more common in animals, thus the many problems we see in many, many breeds of domestic animals. The only instances where I would encourage intensive inbreeding in animals is where there are no obvious deleterious factors present (so, so unbelievable rare!) or where you have outcrossed and are working to make a new line, variety or breed and wish to concentrate good traits while working very hard to eliminate bad traits.

Plants may be another thing altogether, though. In daylilies, for instance, there are no know "pure" lines, as we see in so many domestic animals. Almost all daylilies will be heterozygous for a lot of alleles and are the results of much outcrossing, starting with the hybridizing of species about a century ago. It is my opinion that daylilies may be good candidates for some careful inbreeding, in some cases. Now we don't want to get carried away (as a cautionary tale, just look at what the animal people have done to their charges through "pure-breeding"!!), but there is much that careful inbreeding may accomplish. Of course, we want to be ever vigilant about inbreeding depression and the concentration of bad traits, but since most daylilies are so heterozygous, I doubt we are on the precipice of inbreeding collapse, as are so many domestic animal breeds. I would note however that certain traits seem to be questionable in daylilies already, so concentrating those traits may be unwise. For example, think edges so profuse they don't allow the flowers to open well or weak scapes with oversized flowers, etc. Even without intensive inbreeding in daylilies, there are problem areas and these need to be admitted and faced so that they don't get concentrated into 'ruined finery', so to speak.

To consider inbreeding in daylilies, let us consider an example. Let us say that there is a new, novel trait that has appeared in daylilies and we want to perpetuate that trait and perhaps even intensify it. If the trait is strongly dominant, then we can just cross to most anything, selecting those that express the trait most strongly and those, which combine the trait with other traits for new, novel phenotypes. But if the trait is recessive, then outcrossing it willy-nilly, crossing "pretty to pretty", is liable to give us very little that we want in the F1. Granted, that F1 can be interbred to bring the trait back out, but I have encountered very few daylily breeders who are going through generations of bridge plants to get to the desired outcome. Most seem to chuck the whole batch if they don't have an intro in the F1, though that doesn't apply to everyone and there are already some notable examples of just this type of inbreeding in the history of daylilies. 

So viable options for breeding such a trait would include selfing, backcrossing to either/both parents and/or creating an F1 through outcrossing and then interbreeding those F1 or backcrossing the F1 to the parent with the desired trait and/or the grandparents that produced the trait in the parent showing the trait. While I would hesitate to do anything other than outcross and interbreed the F1 if there are problems in the parent with the new trait, I would also want to look at its parents to see how strong each of them are. 

Since daylilies are highly heterozygous (generally), a weak plant or one with a given problem may not be concentrated for that trait. If the parents of that plant are easily obtainable and/or much is known about them, you may find that the problem trait is a dominant and may be heterozygous. If that is the case, then selfing or any other inbreeding may allow you to select out the desired trait in combination with other good traits and to eliminate the undesired bad trait or weakness. Genetically, things are not always as they seem, or more technically, phenotype is not always a full indicator of genotype. It is only through some experimentation that you can really know what is what genetically, the true breeding value, and thus have a fairly clear idea of the real limitations and strengths of a given cultivar or seedling, and one outcross that produces 10 or 15 seedlings really isn't going to tell you much.

The instance that I describe above is very analogous to animal breeding where outcrossing has been done (except for the selfing, of course) and a new combination of traits is being sought; i.e., a new breed or a new variety of an existing breed. Pure breeding is rather unique to the animal people. Can you imagine the ornamental plant breeder that would be striving to produce a cultivar that never threw offspring that looked any different from itself? (While this does occur in some commercial plant breeding, especially with some of the old, true breeding food plants, it is by far the exception in breeding for ornamental plants.) The thought is laughable and ludicrous, generally speaking, but it is a deadly serious affair to animal breeders where the brainwashing tends toward the notion that each individual of a given breed or line should look like identical twins or clones. Domestic plant breeding is much more in line with the notion of 'landraces' in animals. I think there is a lot to be said for landraces, especially the fact that it is nearly unheard of to find a landrace that is so concentrated for deleterious traits that their very existence is questionable. With that said though, there is a place for inbreeding in both the plant and animal worlds but the practice must be approached with caution and an understanding of the potential pitfalls, along with an eye for the slightest indications of problems. When used wisely, inbreeding is an indispensable tool for the breeder.

What Makes A Good Daylily?

What Makes A Good Daylily?

“What makes a good daylily?” This is a question I often ask myself, and I have been thinking on it for many years. I also often ask other daylily people this question. I get some interesting answers, but in most cases, the answers people give usually starts with the flower and only concerns the flower. My personal answer starts well below the flower with the roots.

The root of a plant is the base from which all the rest of the plant stems. The ability of the roots to uptake nutrients is the source of much of the ability any given plant has to perform. So why do we rarely hear much discussion of the roots of daylilies? When digging and dividing, or planting new divisions, we all encounter the roots of our daylilies. It is true that they are hidden from view on our plants in the garden or field, but we still see them with some frequency, so why do we not think about them much? Of course, I suppose we could often ask this same thing about every part of the daylily except the flower. It is a rare daylily breeder indeed who is giving a lot of focus to any part of the daylily other than the flower.

Since we have all seen the roots on our daylilies when we plant them or divide them, do you pay much attention to the variations in daylily roots? This is something that I pay attention to. I have noted a wide range in root structure from small rounded roots to long, thin roots to long, thick roots to roots that produce rhizomatous growth. Some daylilies produce new fans that are just barely connected to each other and are easily divided, while some grow all their new fans from a solid main crown. The roots of each crown type can be very variable.

From a grower’s perspective, is there much difference in performance based on the roots? Well, in my experience, the answer is yes. I have noticed that the cultivars with small, short roots often are small plants that may not have very vigorous performance (except in some very small dwarf forms). Plants with long roots with lots of feeder roots coming off the main larger roots seem to show a very vigorous performance. Rhizomatous growth may not be desirable for everyone, but for covering an area, it is very desirable. However, in a garden situation where contained clumps are desired, rhizomatous growth is very undesirable. I would note though that I have never seen a rhizomatous type that was a weak plant with poor performance.

The variability of roots and crown structure is very interesting and may be something to which more attention should be paid. It is my experience, for example, that dividing a clump where each fan is separate from the rest in the clump is much easier than dividing a clump where every fan grows from one main crown. While this may not make much difference if you are only concerned with growing the plant in your garden, for breeders and sellers, this can make considerable difference. I would note that I have personally noticed much more crown rot in those types that have one crown from which all the fans grow and that must be cut apart to make divisions, than in other types. The cutting apart of the crown must be much more stressful when dividing than simply pulling apart individual fans.

So should a breeder never use a plant with a joined crown or that shows small roots? I would say no, because sometimes there is a desirable trait that is found with undesirable traits, and the art of the breeder is to recombine desirable traits while eliminating undesirable traits. I have a few breeder plants that show various undesirable traits. There is no way around this, especially when a given plant may have a very unique trait or offer some other very desirable traits. The key to using such plants is to mate them with plants that show good balancing traits. So a plant with one solid crown could be mated to a plant that multiples through making multiple individual fans and the offspring could be deselected based on solid single crowns. In another example, a plant with smallish roots that is not a very vigorous grower could be mated to plants with strong roots and vigorous growth and the offspring deselected for small roots and weak growth. Also bear in mind that not all goals are achieved in one generation, and some traits can be recessive in nature.

One example I would site is Grand Masterpiece, which is a lovely dark purple diploid with very strong rust resistance, but the roots are small and the plant is not a vigorous grower. However, Grand Masterpiece (either the dip or the tet conversion) can produce offspring that are much more vigorous with much stronger root growth. As well, Super Purple, one of the parents and of Grand Masterpiece, is a vigorous plant with strong root growth, so the evidence in that case suggests that Grand Masterpiece has the genes to produce more vigorous offspring and better root systems, as evidenced by some of its offspring. Would I recommend Grand Masterpiece as a garden plant? No. Would I recommend Grand Masterpiece as a breeding plant? Yes.

It is important to understand that some of the things we may grow as breeders are not desirable garden plants, but carry special genes that make them useful breeding plants. It might be a good idea to be very clear as to which cultivars are which, as average gardeners who accidentally buy a highly-touted breeding plant expecting it to be something special may think twice before they invest in more highly-touted daylilies. The public will often equate high price with special performance or garden value, but it is far too often the case that the most expensive daylilies aren’t great garden plants. Instead, such plants may only be of use to a breeder who knows how to select proper mates for them. We need to be careful not to turn off potential gardening customers. With rust on the horizon and more people having less disposable income, I am afraid that we cannot afford to turn off potential gardening customers. I am all for breeder’s plants, but they should be noted as such. I have a few very expensive plants that have many undesirable traits and I would never recommend them for the garden, but I greatly value one or two traits that I am extracting from them, struggling to recombine onto much more desirable garden plants.

When looking at what makes a good daylily, I am first and foremost concerned with how any given daylily performs in a real garden, an average garden. Most average gardeners don’t have the resources to give any particular plant much pampering. It is true that many expensive modern daylilies perform beautifully when kept under shade cloth with automatic irrigation and feeding of very exacting fertilize formulas while growing in expensive and refined growing mixes, but those same daylilies often look terrible and perform even worse in a real garden situation with blazing sun, little or no irrigation or fertilize and average (or worse) soil. So when I look for a good daylily, I am first and foremost looking for a daylily that thrives in average, real-world garden situations.  Roots may play a very big role in that, but genetics and selection will play a big role also.

We can’t expect plants bred from weak stock to come out strong and vigorous in the first generation, unless, as in the example above of Grand Masterpiece, we know something of the parents of the cultivar and then mate the cultivar to vigorous plants that balance its weaknesses. Even then, we may have to go to a second or third generation to combine all the desirable traits of performance and flower that we wish to see. We also can’t expect plants bred in highly pampered conditions to show real-world hardiness, though some of them may. For a breeder who is interested in producing plants that show great garden traits that will satisfy the needs of real-world gardeners, we would probably be best served to grow our seedlings in conditions that expose the weak and highlight the hardy and vigorous.

One thing that breeders should always keep in mind is that selection follows exposure. A negative trait may only be exposed when conditions are present to allow the negative trait to be seen. However, some plants are weak or show major flaws in even the most optimum conditions. Can you imagine how poorly these plants do in average conditions? While such a plant may be introduced for breeding purposes, I would always hope that breeders are very clear about its negative traits so people who just want a nice garden display will avoid it. You may say, “Well, surely the price will keep such people from buying it”, but I fear that is not always the case, as too many people equate expensive with high quality.

So long as we pamper our plants and don’t expose them to some bit of adversity, it can be very hard to know what has good garden potential and what is only good in optimum conditions or for breeders. While many breeders may want to give their cherished specimens the best possible care (and who can fault them? I certainly don’t!), there are many clever ways to test any seedling without neglecting the entire garden. One is to simply remove one fan from your select seedlings and to grow that fan in less than idea conditions to see how it performs. Another is to send divisions to friends who love to garden but do not have great garden conditions or refuse to pamper, and see how the plant performs in their conditions. This may slow down the rate of introduction of new seedlings, but that might prove to be a very good thing. I know more than one breeder who has told me that this or that got introduced too quickly and proved to be a poor plant on down the line after introduction. In a few instances, I know of cultivars that only got introduced after several (or even many) years because of how the plant performed over time.

“Good” daylilies will vary based upon the definition of “good” that each person uses. It seems that for many, many people “good” only concerns the flower. For me, “good” is first and foremost about the plant, its ability to thrive and multiple, and its ability to do so without being pampered. While this may seem simplistic to most daylily fanatics, this is also the greatest concern of most average home gardeners. If the daylily is to remain a popular garden plant and the world at large is to learn of the wonders of modern daylilies, we need to produce daylilies that will perform well when average gardeners grow them and we must to begin to respond to serious disease issues such as rust through testing, breeding and selection. Otherwise, home gardeners are likely to stick to a few varieties they know to be reliable (Stella, Happy Returns, Little Business, etc) and all of our marvelous advancements will go unnoticed, perhaps in time even lost, with huge potential markets untapped.

Pod Parent Selection

Pod Parent Testing to Determine Breeding Qualities of Individual Clones

Brian Reeder

     As a beginner to daylily breeding, I am in no position to speak of details concerning daylily phenotype segregation and combinations, but as a long-term and experienced breeder, I am in a position to speak about breeding and strain formation. I want to state for the record that what I am going to outline below is simply what is important to me. As a breeder, it is up to you to determine what matters to you. The program I am presenting below is simply a stage in my over-all breeding goals. This phase is the foundation of strain development. While I would, as an experienced breeder, recommend strong attention be given to this phase of strain development, I am not saying you should do this. How you approach your breeding is up to you. I hope what I present here gives you good food for thought about strain formation.

In the beginning stages of strain formation, I am most interested in laying down the most basic traits that are required for the best health, vigor and reproductive ability of the given organism. These traits are paramount, as they lay the foundation upon which phenotype traits can then express and reproduce. That is not to say that the physical traits of an organism necessarily cause specific phenotypes, but rather that the heritable health, vigor and vitality of the organism, in part, determines what is possible in the way of phenotype expression. In my own way of looking at a given individual or strain of an organism, I see the advanced phenotype traits as ‘window-dressing’. In other words, they are simply the decoration we apply at the end of a long building process.

To draw this metaphor out a bit, I can say that I wouldn’t want to hang drapes until I had a house built. I would have laid the foundations, framed in the walls and built a roof, then finished out the inside of the structure before I did things like hang drapes or put up pictures, lay down rugs, paint or put up wall paper. Over my three decades of breeding many different organisms, I have come to see phenotype traits as such finishing touches. Much like house décor, these things can be changed. If we are looking at houses to buy, choosing the one with the wall paint color you like the best but a severe termite infestation would not be wise. You would look for a sound house and then paint the walls any color you want. I approach strain formation in the same way, looking for basic, foundational traits upon which to attempt to build a sound strain for later phenotype selection.

To apply that to daylilies we might say that a weak, hard to grow plant may not give the optimum flower performance, that which we might consider optimum for daylilies of similar ploidy in general. Or conversely, we could say that a strong plant may be able to give more energy to flowering. However, I have seen instances of fast growing daylilies that do not produce many scapes, so it is clearly more than vigor that creates optimum scape densities and bud counts or reblooming traits. It would seem such traits have their own genetic basis and thus we may see a slow growing plant have a high scape density or bud count, which is desirable, but simply is not be a strong plant. However, in some instances, we see a combination of vigor with scape density, high bud counts and/or rebloom. In my experience with collecting daylilies for the last thirty + years (I am 43 at the time of writing and have been growing daylilies since I was a young child) I have noticed instances of stand-out cultivars, in both ploidy levels, that show strong, vigorous growth and give excellent performance for scape density, bud count and/or rebloom. In short, such individuals are outstanding plants that are a joy to grow and reward you for the least bit of effort.

A further consideration is that the expression of such desirable traits can vary from cultivar to cultivar to some extent depending upon environmental conditions. Even environmental variations within one garden can cause variable expression of phenotypes in daylilies. So what I consider my best examples for the combinations of all these traits may not be so in another environment. With that said though, there do seem to be some cultivars that are reportedly vigorous and show good phenotype expression in a wide range of environments and even seem to be able to pass such traits on to their descendants.

At this point in my breeding program, I am at the beginning of strain formation. I am not choosing one particular ploidy, form, or color of daylily to focus on. My only focus is finding strong plants with good plant traits that are strongly fertile and are able to pass their good plant traits to their descendants. My first focus is to locate and identify my “females”; i.e., the most reliable pod parents for producing both good quality seed and good quality seedlings showing the same strong plant traits as their pod parent. There are many phenotype traits that I admire; forms, colors, etc., so I am making an effort to bring in a wide range of phenotype traits. I am working with over three hundred cultivars, about 2/3 diploid and 1/3 tetraploid, as well as a few species and species clones. I have cultivars that I have grown for nearly thirty years, to newer cultivars that have only been added in the last year or two. I have spent considerable energy in the last few years researching the traits of various daylilies that interest me, both for phenotype and plant characteristics. I have recently added some cultivars due to their advanced phenotype traits for form and/or color, while others I have added because of numerous reports of excellent plant traits.

So to begin the process of forming strains, I spent a great deal of time thinking on what traits mattered most to me. The list of traits below is arranged in the order to which I assign importance to the given trait. Your order of importance may vary from mine. While you are welcome to use my list if you wanted, I certainly don’t expect anyone too. These are only the traits I consider to be of importance and the order is only the order that I place value on the traits. I would say though that the basis of my trait-ordering is based on three decades of intensive breeding and the recognition of the commonality of certain of these traits across all the organisms I have worked with, as the basis of a superior strain, in both plants and animals.

Here is the list of the traits that I am looking at with each cultivar’s seeds/seedlings. My first major breeding season was 2010 followed by 2011. In 2010, I purchased many new cultivars and purchased seeds of many interesting phenotype crosses. These were to be used to select a small number of vigorous an/or unusual phenotype combinations for use as bridge plants to bring in given traits to the formation of strains. I also produced seeds on a handful of my oldest and most vigorous cultivars. In 2011, I pollinated every clump I had, old and new, in order to test all of those many cultivars against the list below. Each cultivar was generally bred to several different pollen donors but the pedigree, for the most part, was only of the pod parent, as this round of breeding was to find the best seed producers, with the best germination and seedling growth. Only later will consideration of phenotype traits be given, and those identified to have the best expression of the first few traits on the list will be taken on into pedigreed breedings in later seasons, as part of more orchestrated strain formation.

1. Ability to set seeds

2. Quality/quantity of seeds

3. Germination rate of seeds

4. Growth of seedlings

5. Percentages of foliage type from given cultivar (i.e., can cultivar produce dorms)

6. Health and vigor of foliage of seedlings

7. Average time of first bloom of seedling group from given cultivar

8. Quality of scapes of seedlings from given cultivar

9. Quality of flower (sun resistance, lack of spotting, clarity of color, etc.)

10. Potential recessive genes carried by cultivar

11. Range of phenotypes in seedlings of given cultivar (flowers)

12. Possibility of Rebloom

With the full list given, I would like to look at each one briefly below.

1. Ability to set seeds

This one is obvious. If a given clone does not produce seeds, it cannot be a pod parent. Some of these plants may be useful pollen parents. Cultivars that are totally infertile one season may show fertility in later seasons. However, my focus is to find those cultivars that show strong seed production regularly.

2. Quality/quantity of seeds

All seeds are not created equal. Some plants produce copious seeds, but those seeds germinate poorly. Other cultivars produce few seeds, but they show good germination traits. It would then seem that these are separate traits that can recombine. The recombination that I most desire is both good numbers of seeds and seeds that store and germinate well. In other words, seeds which are forgiving and germinate in spite of my care. A good example of this in tetraploids is Custard Candy, in my garden.

3. Germination rate of seeds

Once germinated, survival rates of seedlings seem to vary from cultivar to cultivar. I am paying particular attention to those cultivars that germinate well and then also show high survivability rates of the young germinated seedlings. Again, Custard Candy shows this trait in my experience.

4. Growth of seedlings

Once germinated, even when germination rates are equally high, some cultivars show better growth than others. Those that show the fastest growth are noted.

5. Percentages of foliage type from given cultivar (i.e., can cultivar produce dorms)

I prefer dormant foliage, so when I am using an evergreen or semi-evergreen, I am interested in the cultivar’s ability to produce any dormant offspring. My goal is to work toward only dormant foliage, with hard dormant being the most desired outcome. In some instances, I will probably have to use semi-evergreen or evergreen cultivars, so known dormant carriers could potentially be used to produce dormant foliage in their offspring. I prefer to cull seedlings for foliage type the first winter into spring before I have seen the first flowers.

6. Health and vigor of foliage of seedlings

Nice, bright green to blue green to reddish foliage all look nice to me. Yellowing, chlorotic, streaked, or dying foliage is not attractive to me. Those cultivars that show consistently the nicest foliage, as well as some level of frost resistance, will get special focus. Those that have scored well in all the previous points and show desired foliage traits will gain special focus in my strain formation. To me, this is an extremely important point.

7. Average time of first bloom of seedling group from given cultivar

It has been suggested to me that in breeding for the reblooming trait, those individual clones that bloom earliest, from stock known to express rebloom, show a higher likelihood to show reblooming traits themselves.

8. Quality of scapes of seedlings from given cultivar

I don’t like floppy, weak scapes. I do like strong, thick scapes that can easily support their flowers, more than one at a time. Those plants that show good scapes and also produce seedlings showing good scapes will take a special place in my foundational strain building.

9. Quality of flower (sun resistance, lack of spotting, clarity of color, etc.)

Here finally we reach flower phenotype traits. If all other criterion before this shows good scores, then the flower is considered. Like most everyone, I like sun and rain-fastness. I like a range of forms, color, and patterns. Distinct colors are nice, and clear, clarified colors are even better, but some of the smoky or grayed cultivars as well as brown cultivars, are very attractive to me. The substance of the flower is very important to in my opinion, as is the ability of the flower to open wide. I don’t especially care for more trumpet shaped flowers, though I do like some of the pleated or cristate-formed cultivars. Cultivars that have scored well on all previous criteria and show interesting and desired flower traits will then be given special focus in base-strain formation.

10. Potential recessive genes carried by cultivar

There are certain genes that I value that are thought to be recessive (classical Mendelian recessives in diploids). The ‘melon’ factors/clarification factors, reblooming genes, dormant foliage and rhizomatous root growth are all said to be one or more recessive genes. Instances of a parent that does not display the given trait but can produce it in its offspring are to be noted and made use of. Such plants may only be bridge plants, but they can produce the recessive traits that I have chosen to pay attention to. This one is not really so much a selection criterion, except in a few rare instances, as it is a nice thing to know in addition to the previous criteria. Those plants that have passed all the previous criteria well may get used enough to make determination of heterozygous traits.

11. Range of phenotypes in seedlings of given cultivar

This is the ability to recombine traits, i.e., the lack of homozygous dominant traits - this is broadly the general combining ability. Do the seedlings vary widely or are they very much like clones of the pod parent? The later may indicate a high level of homozygous dominant traits. The f1 from such a cross, while looking like the pod parent, may well carry recessive traits of value. Some cultivars produce consistently nice offspring, while others produce a few nice ones and a bunch of not so nice ones. Those that can consistently produce the most surviving strong seedling plants, with other desired phenotype traits, will be given special focus. At this point, a cultivar or seedling that has reached this level, has scored high in all previous criteria and also produces consistently strong seedlings with acceptable flower phenotype traits will move to the highest levels in strain formation becoming major pod-line founders for use in pod and pollen pedigreed breedings.

12. Possibility of Rebloom

This is my final criterion, as it is the last in the cycle of all the traits that will tend to express in the phenotype, in chronological order. Consistent rebloom is something I very much like and is a very desirable trait. Any plant that consistently reblooms and has shown good traits in all the previous categories will be foundational to reblooming strains, which I would eventually like to find in all my strains of daylilies. However, a fine plant, scoring high in all previous criteria, will still be made use of if it does not rebloom. Perhaps in time I would have enough seedlings that rebloom to go over to nothing but reblooming lines, but that day is probably a good bit away at this point.

I expect only a tiny fraction of the cultivars I have to meet many of these criteria, but it is important to isolate those few individuals that come close. These then can be used to build strains that show many desired traits all combined into single plants, both through interbreeding such plants and by outcrossing them to plants with desired phenotype traits in combination with undesirable plant traits. Such an undertaking is a slow process, but I have found that it does allow for the formation of unique strains showing the combination of many desirable traits, in both plants and animals.