Premium
Population differences in self‐fertility in the “self‐incompatible” milkweed Asclepias exaltata (Asclepiadaceae)
Author(s) -
Lipow Sara R,
Broyles Steven B,
Wyatt Robert
Publication year - 1999
Publication title -
american journal of botany
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.218
H-Index - 151
eISSN - 1537-2197
pISSN - 0002-9122
DOI - 10.2307/2656974
Subject(s) - biology , population , fertility , botany , natural population growth , demography , sociology
Individual plants of Asclepias exaltata (Asclepiadaceae) typically express an unusual self‐incompatibility system under single‐gene control. Hand‐pollinations performed in six natural populations detected occasional self‐fertile plants. The frequency of self‐fertile individuals ranged from 0 to 34.0% and differed significantly among populations. Self‐fertility appears to be under genetic control, as the ability of most plants (80.0 %) to set fruit following self‐pollinations was identical under natural and greenhouse conditions. Seed‐ and fruit‐set, however, were significantly lower from self‐ vs. cross‐pollinations. Allozyme analysis of the population with the highest frequency of self‐fertility revealed that adult plants were not significantly inbred. Finally, fruit‐set following within‐population cross‐pollinations did not differ from that following wide, between‐population cross‐pollinations.