Ken Klemow kklemow at WILKES1.WILKES.EDU
Mon Nov 18 20:18:08 EST 1996

Scott Shumway asks:

>If dioecious plants have male and female flowers on separate plants and
>monoecious plants have male and female flowers on the same plants, then are
>plants with perfect flowers also considered to be monoecious?  My
>impression is that the answer is "no", but I have never been able to figure
>out WHY.  Can someone straighten me out?  Thank you.

Using the term monoecious to refer to bisexual plants with unisexual
flowers, and not for plants with bisexual flowers makes a lot of sense to
me precisely because it conveys the idea that the flowers are unisexual,
and thus have a fundamentally different breeding system compared to plants
with bisexual flowers.  As you may be aware, there is also the phenomenon
of polygamy, in which a plant can have both unisexual and bisexual flowers.
If the plant bears bisexual flowers and unisexual flowers of a single sex,
that plant would be polygamo-dioecious.  If it bears bisexual, pistillate
and staminate flowers, then it would be polygamo-monecious.

Terminology relating to plant sexuality can actually get much more
intricate.  Redford (1986) provides a good summary on pp. 441-444 of his
"Fundamentals of Plant Systematics" text.

Kenneth M Klemow, Ph.D.
Department of Biology
Wilkes University
Wilkes-Barre, PA 18766
(717) 831-4758
kklemow at

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