Ability of Seidenfadenia mitrata (Rchb.f.) Garay, pollinia stored at low temperature on fertilization, pod formation and in-vitro hybrid seed germination

Seidenfadenia mitrata (Rchb.f.) Garay, is one of the beautiful Thai orchids that is rare and has become endangered. Stored pollinia of Seidenfadenia mitrata at 10°C for 17, 42, 44, 49, 307, 314 and 339 days were used to pollinate the flowers of Vanda liouvillei, Aerides multiflora, Aerides rosea, Rhynchostylis retusa, Rhynchostylis gigantea, Vanda lilacina, and Ascocentrum miniatum, respectively to produce intergeneric hybrids. After hand-pollination, the fertilizing ability of seven crosses of intergeneric hybrids remained high with respect to pod formation (50–100%). Hybrid pods of three crosses using stored pollinia of Seidenfadenia mitrata for 17, 24 and 314 days involving Vanda liouvillei, Aerides multiflora and Vanda lilacina, respectively, produced seeds and germinated into protocorms after sowing on modified Vacin and Went agar medium supplemented with 150 mlL^-1 coconut water, 10 gL^-1 sucrose, 7 gL^-1 agar and pH 5.2 for 113, 22 and 36 days, respectively. The survival of three intergeneric hybrid plantlets was 100 % for pollinia stored for 180 days and they were successfully grown in greenhouse conditions for 360 days. Storage of Seidenfadenia mitrata pollinia at low temperatures is successful on keeping the desirable male parents for hybridization and conservation.