Effect of Plant Growth Regulators on Sporophyte Formation from in Vitro Cultured Prothallus of Bracken Fern

Present studies were conducted to evaluate the effects of composts, prothallus chopping time, inoculation amounts, and growth regulators on sporophyte formation from prothallus of edible Pterdium quilinum var. latiusculum. Horticultural compost was most effective in sporophyte formation and growth from chopped prothallus among 8 different soil media containing horticultural compost, peatmoss alone or with vermiculite and perlite. On chopping the prothallus using grinder for 5 to 30 second, optimum prothallus chopping time was 10 seconds for excellent sporophyte formation and growth. Various amounts of prothalli, ranged from 0.5 to 4 g, were placed on horticultural compost. Optimum amount of prothallus inoculation for the best sporophyte formation was 2 g when growing on 9x14 cm pots. To determine the optimum kind and concentration of plant growth regulator, and soaking time on formation and growth of sporophyte from prothalli, 2 g of prothalli were soaking in 20, 50, 100 mg.L-1 of GA(3), NAA, kinetin, IAA, and BA for 1, 3, 6 hours. After wash and grind for 10 seconds, prothalli were cultured on horticultural composts. The most efficient condition for sporophyte formation was observed with soaking in 50 mg.L-1 GA(3) for 3 hours, while the vigorous growth of sporophytes was in 100 mg.L-1 NAA for 6 hours.