Re: Seed Development and parentage

Dear Friends,
       Admittedly my biology is elementary and I know a bit more about 
animals than plants, but remember that an ovary produces eggs, but does not 
harbor the fertilized ova. That takes place in the uterus, or whatever the 
botanical equivalent term for the seed capsule is.
       By analog, and by experience, I can assure you that in the ovulation 
of a Bitch several ova can be released, and if this female canine is exposed 
to more than one opportunistic Dog, she can have pups in the same litter by 
multiple fathers.
       We certainly know that setting seeds in plants diminishes flowering, 
i.e., ovulation, in many species. That is why we dead head (abort) 
perennials, so they will keep ovulating. Similarly fertilization in a female 
animal inhibits ovulation until the offspring have been born and weaned. But 
during the fertile window, sperm from multiple donors is potentially 
acceptable.
       I am confident that if mixed pollen from multiple potential parent 
iris were mixed and placed on the stigmatic lip, that there would be some 
random fertilization as long as the chromosome count was compatible, perhaps 
modulated by the robustness of the pollen producer, but surely one 
fertilization does not inhibit others that are more or less simultaneous in 
time but have equal potential.
       Let's keep in mind that the plants is producing at least as many, but 
surely many more ova, than any resultant seed.
       Also let's keep in mind that the ova carry nutritive materials which 
make them appear larger, even visible in some animals, but that the DNA in an 
ovum or sperm is microscopic (and in plants I suspect for the most part that 
the ova are microscopically small as well. While we can clearly see grains of 
pollen, I am confident that these grains are comparable to drops of ejaculate 
which contain multiple but microscopic spermatozoa which are invisible to the 
naked eye.
       Apologies for my lack of precise botanical knowledge and nomenclature, 
but I believe my basic biology is correct in this case. 
       When the window of fertility is open, multiple fertilizers (and here I 
am not talking about nitrogen, phosphorus and potash) are acceptable. When an 
ova  accepts a sperm, then that window closes. (Possibly there is some more 
general system shutdown when the potential capacity of the plant to mature 
seed is reached, but surely not just because one ova accepts one sperm.) 
       I would be pleased to be instructed if these basic principles are 
incorrect. They do regress to the most basic commonalties of sexual 
reproduction which is shared by almost all animals and most plants, but 
please tell me if my general summary is incorrect.

James Harrison
Asheville, NC


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