Evaluating the genetic and floral type effects on inbreeding depression in dimorphic cleistogamous plant Viola philippica Cav.

Avoidance of inbreeding depression is thought to be an important selection force for maintenance of chasmogamous flowers in dimorphic cleistogamous plants. Inbreeding depression may be caused by genetic (outcrossing and selfing) and floral type (chasmogamous and cleistogamous) effects in cleistogamous plants. This study aims to distinguish genetic effects on inbreeding depression from floral type effects by comparing the performance in growth between offspring of cleistogamous flowers, selfed and outcrossed offspring of chasmogamous flowers in perennial herb Viola philippica Cav. The fitness, in terms of seed size, germination rate, plant height, number of leaves, were estimated. Data showed that the fitness of outcrossed offspring from chasmogamous flowers was the highest, followed by selfed offspring from chasmogamous flowers, and the offspring from cleistogamous flowers was the smallest. These data suggest that both genetic and floral type effects contribute to inbreeding depression in offspring from cleistogamous flowers in dimorphic cleistogamous plants, and genetic effects play a major role.