Pollination and fruit production of native
species in fragmented remnant vegetation.
Mr. David Duncan, Australian National University, Department of Botany & Zoology Grant details
This work has demonstrated a process by which even common plant species in fragmented vegetation can suffer declining reproductive success through reduced outcross pollen receipt, combined with increased inbreeding (for self compatible species).
A spacial survey of pollen load and fruit set in over 800 individuals of Dianella revoluta, Eremophila glabra, and Senna artemisioides, in edge and interior plots, showed significant clumping of high and low pollen fruit set values. However, even the most isolated plants within one hectare plots can get substantial amounts of pollen, and set fruit. So far no differences have been found between edge and interior plots in these species.
Further experimentation work with Dianella revoluta has demonstrated that most pollen deposited on stigmas during pollination visitation is self-pollen transferred within flowers (anther > stigma).
Flowers on isolated plants get similar levels of pollen visits compared with flowers near their potential mates, but the amount of out cross pollen received at isolated flowers declines sharply over relatively short distances (<50 m).