Pollination Biology of Chirita lutea Yan Liu et Y. G. Wei in China (Gesneriaceae)

Abstract:

Chirita lutea, which was published in 2004 by Liu and Wei, belonging to Gesneriaceae and only distributed in Guangxi Province of China, is a perennial herb and grows on limestone rocky hillsides or cliffs. The species can produce abundant flowers every year, but it currently presents the small populations. The pollination biology in C. lutea was studied. Flowering of C. lutea took place from early July to late August. The flowering period of individual lasted about 35~47 days, while anthesis of single flower lasted 6~12 days. Flowers opened at noset time. During anthesis, the pollen viability retained at about 80% and the stigma receptivity retained at about 75%~90%. The mean P/O was 1215.73±266.13. The stigma was obviously higher than the anther after flowering 1 day and reached the entrance of collar tube when the pollen was dispersed, which easily made it to be touched firstly by pollinator and receive allogamy. Field experiments indicated that C. lutea was self-compatible and there was no agamospermy. The pollination must depend upon insects because the occurrence of autonomous self-pollination was difficult. Pollination limitation is existent in this species, so the fruit set in the artificially pollinated flower was higher than that in the open pollinated flower. The main pollinators are Apidae sp., Crabro sp., Amegilla sp, which visited the flowers for pollens.

Key words:Chirita lutea; Floral biology; Pollination; Breeding system