My sunflowers have what I'm guessing are fairly normal looking anthers, but I really am a noob at botany, particularly the reproductive parts. I'd like to know if they have CMS or not before they set seed, so I can make informed decisions about what to save. If anyone wouldn't mind taking a look for me, I have some pictures I hope are close up enough. (If I need better pictures, please let me know how I can make them more useful, and I'll try again.)
Complete flowers have all four floral organs. The floral organs consist of sepals, which are small, green, leaflike structures at the base of petals; petals, which are the colorful part of the flower; female sex organs, including the ovary and ovule, which together are called the pistil; and the male sex organs, including the pollen-producing anthers, which together are called the stamen. If a flower is missing any of those parts, it is incomplete but still could be considered perfect. If, for example, a flower is missing sepals but has male and female reproductive organs, it would be a perfect flower; because not all four floral organs are present, however, the flower is also incomplete. Sunflower ray florets are missing both stamen and pistil, making them sterile. Sunflower disc florets are perfect flowers and create fruit when fertilized. That fruit is sunflower seed.
I had not heard of CMS so would you explain how this would affect the seed production?
Invasive plants are Earth's way of insisting we notice her medicines.
Everyone learns what works by learning what doesn't work.
Anne Miller wrote:I had not heard of CMS so would you explain how this would affect the seed production?
Joseph Lofthouse has written on it a fair bit, but most of his pictures are of carrots. It's Cytoplasmic Male Sterility. Plants with CMS can't produce pollen. Therefore any seeds produced by that plant have a different variety as the father. Needless to say, the trait is inherited from the mother. Not always SO terrible, but if you grow only one variety, you either won't get fertile seeds, or the ones you get will be 50% what your neighbor grew, or 50% a wild relative. (In carrots, this can mean the F1 is 50% Queen Anne's Lace, F2 is 75%, etc.) You can pretty quickly loose the genetics you were trying to preserve. Joseph culls out any plant with CMS so his saved seeds won't have it. I think that may be wise for me to consider as well.
Forgot to mention: My understanding is that CMS can be caused by genetic modification (GMO), but isn't necessarily. In at least some species, it occurs naturally. No idea which is the case for sunflowers.
Jan White wrote:I'm far from an expert, but the anthers seem to be present so as long as they get pollen on them you're good to go. No?
I would think so. I tapped 'em a few times and didn't see anything, but I hear things can shed pollen one part of the day, but not another. I'm hoping I was just there at the wrong time, but we'll see. My next move will be to check out the article linked above. Maybe I'll learn something useful.
Jan White wrote:https://www.gardeningknowhow.com/ornamental/flowers/sunflower/pollenless-sunflower-varieties.htm
I just skimmed the first article in my search results, but it sounds like they won't produce seed anyway.
I think, but don't know for sure, that the author was mistaken, or only partially right. Since a typical sunflower has both male and female sex organs, if the male part isn't working, that particular plant can't produce seeds alone. I don't see why it couldn't produce seed with the help of a pollen donor. That would be a hybrid, which I don't mind, but in the next generation the mother's genetics are already half gone, and it'll happen again because CMS is inherited from the mother. In a few generations the genetics of the mother will be diluted into oblivion, all except for the CMS. The offspring get to keep that forever.
Here's a link to something Joseph wrote on the subject. I suspect it's a little more enlightening than my writing.
I'd forgotten the terms until one of the articles reminded me, but it looks to me as if they have styles. On the red one, I think I can see anthers. Not really sure on the yellow one. I'll try to get a look at the actual flowers. I'm not sure my pictures are high enough resolution. I'll also try to watch for pollen and pollenators. Only a few sunflowers survived from our first planting, but we planted again last week. Some of them actually came from Joseph in a trade. I think there's still time before frost to get a look at those blooms. I know they'll be normal, so that should give me something to compare to.