Friday, July 27, 2012

Extremes

The Danger of Extremes in Phenotypes


I just wanted to write a few words about the race toward extremes in phenotype that we so often see in the breeding of domestic plants and animals. While this is very common, and might in fact even be considered the essence of phenotype breeding, it can be dangerous to the health, well-being and continued popularity of any given domestic population. This, of course, depends on what the 'extremes' in question may be.

In the case of selection toward extreme examples of hardiness, disease resistance, fertility or adaptability to varied climate/environmental conditions, we would not be seeing something dangerous to the genus, usually. However, when the selection for extremes in daylilies specifically involves larger and larger flowers without the plant underneath them to support them, wider edges with bigger and bigger bubbles/teeth/ruffles that open poorly, pretty faces regardless of the plant qualities, tall/weak scapes that can't support more than one giant flower open at a time (if even the one), extreme flowers that cannot perform in average garden conditions and require ideal conditions or greenhouses to fully express there phenotypes, pretty faces that are not fertile, and plants that are weak in general, that cannot tolerate real-world conditions or have no resistance to diverse conditions including stress factors such as drought, heat, cold or disease, then the extremes can be creating a two-fold danger.

The first of these dangers is that we are creating a weaker plant that cannot thrive (or perhaps even survive) in a real-world garden, thus loosing the public interest. The second danger is the erosion of the genome of many lines that could potentially bottleneck into a dead-end due to health and/or fertility issues, leaving us with only vegetative reproduction (where such plants are able to increase enough to even be multiplied) without any hope of continued sexual reproduction and thus, no hope of new cultivars from those lines.

While what I am proposing here may seem extreme (and we are admittedly not yet at the precipice), and many may see this as only fear-mongering, all we need to do is look at the history of some of the other domestic lines of animals and plants that have been selected for extremes for a long period of time to see such negative potentials made manifest. There are many examples in the animal world and plant world of domestics that have been selected out of existence or to the brink of existence through a focus on extremes at the cost of survivability/reproducibility.

While I am not suggesting that everyone should start breeding for extremes of hardiness or resistance, I would suggest that keeping hardiness and plant qualities in the back of your mind, at all times, is a good exercise for all plant breeders. It certainly can't hurt, and maybe it will help. Maybe, the next time you have a wonderfully pretty face on a poor plant, instead of introducing it, you could just save it for use as a breeder and work to bring its lovely traits onto a better plant? I know many good breeders already do this. Good breeding requires patience, and all good things come to those who wait. While it has been suggested that patience is the reward of patience, in breeding plants or animals, the reward of patience is often a much better end product.

Tuesday, July 17, 2012

Traits of Daylilies

Traits of Daylilies:

A Consideration of Extreme Points on a Spectrum

As I discuss various trait sets below, it is important to remember that most of these traits will fall along a continuum so that only a few cultivars may fall into the most extreme ends of any given trait set. Further, please bear in mind that these descriptions are only my thoughts and opinions, based on my own experiences in my own gardens. Now, of course, I think my thoughts and opinions are right on target... for me, but they may not be on target for you. A trait that really irritates me may be one that you really like. To each their own! You have to decide what you like or don't like. Clearly, I have made some decisions about what I like and dislike. Please, never take any of my posts to mean that I am telling you that my thoughts are written-in-stone facts, or that I think you should follow my methods or agree with my thoughts. Think of all my posts as my process of thinking out loud, a process through which I am working to iron out my focus for my own breeding program. Please take anything that you like or agree with or want to integrate into your own program and ignore that which does not apply to you or your program. 


It is my belief that there are no "bad" daylily breeders. I suspect that every introduction from a given breeder was beautiful in their own rearing system. There are certain hybridizers that I have many introductions from, yet in no instance has every cultivar I have from any one of those hybridizers been a winner for me (though some have more winners in my gardens than others...). I think that would be a given for any and all hybridizers efforts. They are simply not all going to work for everyone, in every situation. I try to be realistic about that and I want to state this belief upfront. As well, I want to reiterate that I like all types of daylilies, every flower form/type, all colors/patterns, all heights and both ploidy levels. I think evergreens and semi-evergreens have there place, but that place is not necessarily in my garden.

So, with all of that said, on to the trait sets. Below is a bullet point list of the main trait sets that I will be focusing on for this series of blog posts.

  • Disease tolerance vs disease susceptibility
  • Drought tolerance vs drought susceptibility
  • Fast increase vs slow increase/non-increase
  • Plants that thrive in diverse conditions vs poor performers
  • Healthy foliage vs problem foliage
  • Dormant foliage vs evergreen foliage
  • Scape strengths vs scape weaknesses
  • Flower pigment fastness vs flower pigment spottiness
  • Reliable flower opening vs poor flower opening
  • Fertility vs infertility

I will now talk a bit about each of the trait sets to provide an introduction to my general thoughts on them.

Disease tolerance vs disease susceptibility


Disease is a given in all organisms. Nature has provided an array of methods to fight off attack by various pests and pathogens. In domestic breeding we wish to incorporate as many methods of defense into our lines as possible. However, this is no easy task. To begin with, you actually have to see the problem you wish to breed tolerance for in your garden and then you have to select those individuals that show some level of tolerance as breeders. Gardens that suffer rust, rot, spring sickness, thrip damage, or any new problems that may arise, are in a position to select toward tolerance. Gardens that do not experience a given problem are not suited to selection for tolerance levels. Yet in time diseases may spread, and if so, tolerance will become an important aspect of breeding programs in gardens that once did not have to consider such things.

An example of this in my garden is rust. I have never seen rust in my own garden. I have, however, brought in several cultivars and seedlings that have shown high rust tolerance. I will test them out for my important criteria and then utilize any that pass in my own breeding program. However, unless I start seeing rust in my own garden (which I suspect is inevitable due to increasingly warming climates), I cannot select for rust tolerance. Until such a time as I do have rust in my garden, my path will be to send select seedlings descending from these rust tolerant individuals to gardens infected by rust to see if any of the tolerance of their ancestor(s) has passed on to them. That is all that I can do in this regard at this time, but it is still a consideration for my program.

Tolerance to disease makes a given cultivar easier to grow when such a disease is present, and more attractive in such settings. Such plants are very desirable when disease is present. Intolerant plants are unattractive, may even die and at the very least present an unattractive garden display. Such plants are undesirable in diseased settings. Further, such plants are not enjoyable and will likely reduce the desirability of the daylily, in general, to the gardening public at large.


Drought tolerance vs drought susceptibility


This year has certainly shown the need to select for drought and heat tolerance. Those cultivars that are drought susceptible are unlikely to survive this year without extensive watering, and that is something I am unwilling to do, as I practice xeriscaping, being located on a southern slope with a sand and clay mix soil and I don't want to spend all my time watering. I have grown various daylilies in this setting for the last twenty-one years and many flourish, while some do not. By using those which flourish in a dry setting, I can select toward tolerance to dry conditions. Anyone with a dry garden setting can make this type of selection, if they don't give supplemental watering, or only sparingly.

With that said, I don't blame anyone who does water. Please don't think I do! There are situations where you will want to water and not everyone will want to practice xeriscaping as I do. For instance, if you have a display garden, special seedlings you wish to increase, are raising divisions to resale or have very special seeds you wish to ensure reach maturity you will want to give supplemental watering, but I would point out that watering plants in dry conditions means you may not be able to select for tolerance to dry conditions. Consistent watering in dry conditions creates a negative selection pressure wherein those without drought tolerance (susceptibility) survive and pass their genes on to future generations. If climate conditions continue to change, we will likely see more heat and drought as a result. It is something to consider. The key is to test all potential breeders in non-watering situations. I will have more to say about this in a future post.

On the opposite side of drought tolerance is tolerance to high water/humidity levels. In rainy seasons, my soil is very saturated due to the clay content and holds a great deal of water. Daylilies are remarkable plants, in that many of them can survive a wide range of conditions. There is some suggestion that high humidity/water and heat may contribute to rot. Those cultivars that can flourish in both very wet and very dry conditions are very special. I am paying particular attention to those that show such diversity of tolerance in my own program.


Fast increase vs slow increase/non-increase


The increase of fans shows a wide range of expression. Some cultivars increase rapidly, while others never seem to increase at all. The worst end of this spectrum is those that not only don't increase, but actually decrease. I have to think that most of the slow growing cultivars probably grow well enough in their home gardens, but likely that is under the most ideal of conditions. In an average garden, some cultivars just don't grow well.

I have spoken with breeders who do not like fast growing cultivars because they say they have to be divided too often. I have also heard slow growing cultivars referred to as being preferable, "hybridizer's plants", because they do not increase as quickly and do not need frequent division. My feelings are completely different. I do not have a problem with moderately increasing cultivars, but I do not like slow growing cultivars that take years to increase a few fans or never increase at all, in my setting. To me, the advantages of fast increasing cultivars is that they can be multiplied more quickly both for distribution and for use in garden settings. I also just like a really large, mature clump of daylilies.

The one disadvantage to some cultivars when they grow into large clumps is that scape count can be suppressed. However, this does not occur in all cultivars. I have grown many older cultivars for years that can be very productive and produce a wonderful display with lots of scapes when in a large, mature clump. The key to produce such plants is, of course, to use such plants as breeders.


Plants that thrive in diverse conditions vs poor performers


Some plants perform wonderfully all over the country, in every zone. These are what I call 'generalists', being that they are adaptable to a wide range of conditions. Other cultivars only seem to prosper in very narrow bands of the continent. If you happen to live in that small region where such plants flourish, they are great, but if you don't then such plants are a great disappointment when the attempt is made to grown them. While daylily enthusiasts may understand this, the general gardening public will not and can be easily turned of by highly-touted but poorly-performing, regionally specific cultivars.

I pay special attention to plants that are known to flourish all over the country. The Lenington Award winners are often good examples of such generalist plants and are a good place to start when selecting breeding stock for diverse conditions. Those who wish to breed plants that can be successful in a wide range of environments should look for plants that are known to thrive in a wide range of regions and conditions.

One of the major agricultural philosophies that I use is the Law of the Minimum. Stated simply, the necessary element for survival that is in the least supply limits the population. Daylily cultivars that survive the best in severe circumstances and that perform well in the widest range of areas and drastically different environments push the boundaries of the Law of the Minimum. By breeding from such plants, it may be possible to increase the definition of 'the minimum' for daylilies, in many regards.


Healthy foliage vs problem foliage


I pay a lot of attention to foliage. Stated simply, I detest ugly foliage, and lots of daylilies seem to have really ugly foliage. However, not all, as some show beautiful foliage, even in poor conditions. There are many types of problem foliage, but the biggest problem to me is yellowing, dying foliage. Some daylilies though will have foliage more yellowish in tone, but that survives well and does not brown and look hideous after two or three hot or dry days. While it is not my favorite color of foliage, I do not mind such plants. The foliage that I find most attractive is the blue-green foliage that does not yellow out badly and that shows good drought tolerance. There are many other considerations with foliage such as frost tolerance, heat tolerance, drought tolerance, etc. I will touch on this subject in more detail in future posts.


Dormant foliage vs evergreen foliage


Stated very simply, evergreen and semi-evergreen foliage drives me crazy in the cold parts of the year. I like those dormants best that go completely underground with the beginning of cold weather and don't come up too early. They appear clean and neat to me during the winter. There are evergreens and many semi-evergreens that survive and thrive in the winter, but they are simply unattractive to me. For anyone who they don't bother, they are fine, if they are winter hardy. For those in the south, I think evergreen and semi-evergreen cultivars are preferable. However, it should not be mistaken that I am saying that all evergreen and semi-evergreen are not cold hardy or that all dormants are only for the north. Some dormants flourish in the warm south, just as some evergreen and semi-evergreen flourish in the cold north. My stance on the foliage types is purely my own aesthetic. In spite of that, there are instances where I will continue to grow and breed with both evergreen and semi-evergreen cultivars. I will touch more on this in later posts.


Scape strengths vs scape weaknesses


Here is something of a major pet peeve to me. I simply hate weak scapes, in most instances. I prefer scapes that are perfectly vertical. I can tolerate scapes that may lean out as much as 15-25 degrees. Any lean beyond that is a major flaw, in my opinion, no matter what the flower looks like and makes me want to compost the plant immediately. I might on rare occasion use such a plant as a breeder if there are other very exceptional performance qualities, but that is a great rarity. The only exception to this rule is with very short border-type cultivars such as Stella De Oro and descendants where the trait is not horrible, but I don't really even like it in that group of cultivars.

There are several types of scape weakness. Some just fall over at the base or the base of the scape cracks or bursts. Other scapes are strong at the base, but then get thin part way up and curve over. Some scapes simply can't hold up their large flowers. Large flowers need very thick, strong scapes. Some cultivars have very thin scapes that haven't the ability to hold up any sized flower.

I have had people tell me that a given flower is so wonderful it is worth staking, but not in my garden. I have better things to do than run around staking up weak stems, especially when there are so many lovely daylilies with strong scapes. I will have much more to say about this trait in future posts.


Flower pigment fastness vs flower pigment spottiness


Again, a really simple thing. I don't like spotty, splotched, melted flowers, even in heavy rain or bright, strong sun. There are cultivars from every color that do not show spots and pigment bleed/melt. I see no point in working with flowers showing these flaws, as if there is any genetic basis to these traits (and there likely is), then using such plants probably passes the problems into future generations. More to come...


Reliable flower opening vs poor flower opening


I will eventually have a lot to say about this, but in simplest terms, flowers that don't open well are not popular with me. Twisted messes, stuck pie crusts, faded blooms gumming up other blooms, trumpet forms on cultivars that are supposed to open out fully, flowers too close together to allow full opening; these are things that make me contemplate the compost heap. I am more understanding of poor opening on late fall rebloom or on very cold morning. What I really hate is when the plant in optimum conditions and its normal season of bloom still doesn't open well. We will explore this more in future posts.


Fertility vs infertility

Fertility is very important to me, not just for my momentary gratification or to get out as many seeds as possible (though that is not a bad reason in and of itself), but because our selection of breeders influences the future of our lines. Using breeders with fertility problems may cause fertility problems in future generations. The issues of fertility in daylilies is a big subject and will require future posts to be explored well. In short, I place strong emphasis on breeders that show strong pod fertility with preference for strong pod and pollen fertility in a given cultivar. I may at times use pollen parents that show little or no pod fertility, but they should then always be crossed over strongly pod fertile cultivars and any breeders chosen from such a cross would be backcrossed to strongly pod fertile plants with further selection toward pod fertility applied to subsequent generations. The ideal cross though is strongly pod and pollen fertile x strongly pod and pollen fertile, where possible in my own breeding program.
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In future posts, I will write about each of the above criteria individually, looking at them in greater detail and giving more of my opinions and observations on each. I hope you enjoy these posts and find them useful, but please always remember that these are only my thoughts, opinions and observations and are only meant to apply to my own garden and breeding program. You may have different criteria and some of mine may not apply to you at all. In such a case, do not take it that I am saying my criteria should apply to you. Thank you!!
Brian Reeder
zone 6/7
AHS region 10