Fertilizing Ability of Cryopreserved Pollinia of Luisia macrantha, an Endemic Orchid of Western Ghats

A successful protocol for long-term preservation of pollinia of Luisia macrantha Blatter & McCann., an endemic and endangered orchid of Western Ghats has been devised through different pollen cryopreservation methods and by confirming fertilizing ability. Pollinia subjected to 0-30 min dehydration at 27 ± 2°C within a laminar air flow cabinet showed maximum germination of 65 - 67% in desiccated controls and 54% in LN treated samples. The treated pollinia retained fertilizing ability, giving 100% fruit set upon sib-mating. Pollinia dried under charged silica gel for 120 min gave 51 - 52% pollen germination, in LN treated and desiccated control samples. Exposure to vitrification solution (PVS2) was optimized at 10 min to achieve 57% and 56% germination in control and LN treated samples, respectively. These pollinia exhibited 51% pollen germination after 668 days storage in LN. Cryopreserved pollinia (10 min PVS2) used for hybridization with Vanda tessellata gave 87% fruit set and 21% viable seeds. The viable seeds germinated and developed into healthy seedlings. Thus cryopreservation has been proved useful for the successful storage of L. macrantha germplasm and their utilization in breeding.