Are plant seeds pre-disposed to be one sex or the other?

Question

I'm writing a paper for class and I'd like to know from all you botany buffs out there - are plant seeds pre-disposed to be one sex or the other? In my opinion, seed pre-disposition means that the seed will have one stronger chromosome than the other. In other words, a plant will have both chromosomes, but either the male or female chromosome will be dominant, with the other dormant?
If we don't agree that seeds are pre-disposed, then what does this leave? This leaves a-sexuality, and hermaphroditism. Hermaphroditism is when both chromosomes are of equal dominance in the plant. It is also presently believed that the hermaphrodite 'gene' is stronger than either just male or female on it's own (this info' came from a breeder, i haven't checked it out). Can a plant be born a-sexual? Can it determine its sex by the environment?

So what say you in the great debate of nature vs nurture, oh mighty botanist? Maybe there's no debate.. I don't know.

How about cannabis? We know that cannabis is not considered some plants and it reproduces similar to the way that we do.

Answer 1

Yes and no, but not in the way you think.

Some plants are asexual and don't reproduce through sexual reproduction. All of their offspring are in reality clones of the original.

Other plants and all flowering ones have both sex organs present in the same plant (but like humans some flowers can be only male and others can be female). They can't reproduce with themselves though only with other plants of the same or very similar species. This is where the concept of pollination comes into play. Unless the bees spread the pollen between blueberry and strawberry plants those plants won't form seeds and reproduce.

It is surprising how much of our food supply depends on bees, and this is totally because of the sexual nature of their reproduction. This is becoming a problem because for some reason the European bee in Europe and the US are dying off in record numbers. It is suspected to be a virus that came from Israel.

Sex and plants is a very complex issue and there are 11 different types of sexual reproduction methods used in plants. Some of these methods require that the plant has both sexual organs, like flowers, others are unisexual, and others have no sexual organs; most of them have

According to Wikipedia: http://en.wikipedia.org/wiki/Plant_sexuality#Individual_plant_sexuality
"Specific terms are used to describe the sexual expression of individual plants within a population.

- Androecious - plants producing male flowers only, produce pollen but no seeds, the male plants of a Dioecious species.
- Dioecious - having unisexual reproductive units with male and female plants. (flowers, conifer cones, or functionally equivalent structures) occurring on different individuals; from Greek for "two households". Individual plants are not called dioecious: they are either gynoecious or androecious.
- Gynoecious - plants producing female flowers only, produces seeds but no pollen, the female of a Dioecious species. In some plant species or populations all individuals are gynoecious with non sexual reproduction used to produce the next generation.
- Hermaphrodite - A plant that has only bisexual reproductive units (flowers, conifer cones, or functionally equivalent structures). In angiosperm terminology a synonym is monoclinous from the Greek "one bed".
- Monoecious - having unisexual reproductive units (flowers, conifer cones, or functionally equivalent structures) of both sexes appearing on the same plant; from Greek for "one household". Individuals bearing flowers of both sexes at the same time are called simultaneously or synchronously monoecious. Individuals that bear only flowers of a single sex at one time are called consecutively monoecious; protoandrous describes individuals that function first as males and then change to females; protogynous describes individuals that function first as females and then change to males.
- Subdioecious, a tendency in some dioecious species to produce monoecious plants. The population produces normally male or female plants but some are hermaphroditic, with female plants producing some male or hermaphroditic flowers or vise versa. The condition is thought to represent a transition between hermaphroditism and dioecy.
- Gynomonoecious - has both hermaphrodite and female structures.
- Andromonoecious - has both hermaphrodite and male structures.
- Subandroecious - plant has mostly male flowers, with a few female or hermaphrodite flowers.
- Subgynoecious - plant has mostly female flowers, with a few male or hermaphrodite flowers.
- Trimonoecious (polygamous) - male, female, and hermaphrodite structures all appear on the same plant.
- Diclinous ("two beds"), an angiosperm term, includes all species with unisexual flowers, although particularly those with only unisexual flowers, i.e. the monoecious and dioecious species."

I am sorry there is not much of a debat on the issue that some plants may have more males than females, since most plants are rooted they don't handle sex like animals do.