Mating strategies of Vitex negundo L. var. heterophylla (Franch.) Rehder
(Lamiaceae): a mixed mating system with inbreeding depression.
Plant reproductive ecology is one of the research hotspots in ecology.
With the increasing attention paid to the conservation of plant
diversity, the research on reproductive characteristics and flowering
biological characteristics of more species has attracted more attention.
However, plant reproduction is affected by multiple interacting factors
such as pollen limitation and resource availability. Vitex negundo var.
heterophylla (Franch.) Rehder (Lamiaceae) is a significant species for
water and soil conservation. Previous studies have revealed its mating
system by the biological characteristics of flowering and SSR markers,
but its reproductive strategies remain to be further studied. We
evaluated reproductive success through artificial pollination to explore
the reproductive characteristics of V. negundo var. heterophylla for the
first time. From the results of fruit set, there is a mixed mating
system dominated by outcrossing in V. negundo var. heterophylla
accompanied by self-compatibility, and it cannot carry out autonomous
selfing. Our data shows the pollinator-mediated interaction in the
success of reproduction, whereas the effect of anemophily is very weak.
And the seed germination rate of inbred line progenies was lower than
that of hybrid progenies, which is suspected to be caused by inbreeding
depression. The research will provide scientific information for the
protection and conservation of V. negundo var. heterophylla from the
point of view of reproduction. In sum, the results are necessary to
protect animal vectors in the background of insect decline.