Comparative study on cross-compatibility between Camellia sinensis var. sinensis (China type) and C. sinensis var. assamica (Assam type) tea

Tea has long been a well-known crop for its economic value and widening the genetic variability of tea family is often necessitated.Hybridization programs at intraspecific level have been greatly fascinated as potential and useful methods in tea plant breeding to widening the genetic diversity.This comparative study was intended to explore a new avenue to develop the tea plant breeding programs through evaluating remote intraspecific cross-compatibility between Camellia sinensis var.sinensis (L.) O. Kuntze and C. sinensis var.assamica (Masters).Remote intraspecific cross-compatibility was assessed by comparing and contrasting the in-vivo pollen germination and pollen tube growth using fluorescence microscopy and the subsequent fruit set following controlled self-and cross-pollinations.In-vivo pollen germination and pollen tube growth was examined at 1 day, 3 days, and 14 days after pollination treatments, but disparity was not observed in pollen germination and pollen tube growth between self-and cross-pollinations.Early fruit set was evaluated at 3 months and 6 months after pollination.Fruit set was observed in cross-pollination except self-pollination.A late-acting selfincompatibility system or post-zygotic barriers and close intraspecific cross-compatibility were confirmed within C. sinensis var.sinensis (L.) O. Kuntze.Potential remote intraspecific crosscompatibility was recorded from cultivars crossed between China type and Assam type tea.The present findings bestow the significant contribution to develop the future tea breeding programs.