การปรับปรุงสูตรอาหารสำหรับเพาะเมล็ดและเลี้ยงแคลลัสกล้วยไม้ ด้วยการใช้สารอินทรีย์เป็นองค์ประกอบพื้นฐาน / วรรณวิภา อิฐรัตน์ = Improving orchid culture media for seed germination and callus culture by using organic substances as basic components
Formulation of culture media using potato, tomato, and fish emulsion as basic components and 13 inorganic salts as supplements were made for growing orchids in vitro. A total of 62 new formulations and three know formulae were used as controls. A selection of media was made on good typical growth of the germinating seeds, young seedlings, and callus formation from seeds or buds from young shoots of the members of Dendrobium. A group of selected media which supported good to very good growth was used for further tests on other genera. The genera used in testing were Brassocattleya, Rhynchostylis, Spathoglottis, Vanda and Vandopsis. The media containing three organic components and 13 inorganic salts gave much better results in seed germination and seedling growth of Dendrobium than the medium made basically with organic salts. A group of the selected media comprising ones with only organic components and the others with different combinations of organic and inorganic components were used in seed germination of Rhynchostylis, Vanda, Vandopsis and the rearing of the seedlings of Vanda. The results obtained in these genera were very much the same as the genus Dendrobium. However, much deviations were found in other genera. In a medium containing only three organic components, seed germination and seedling growth of the Brassocattleya exceeded all other media tested. Fresh weight of 4 month old seedlings was at lest five times of the ones grown in the inorganic medium (control). Similar results were observed in the culture of Rhynchostylis seedlings. Unexpected result was discovered during seed germination of Rhynchostylis. Most of the seeds proliferated into callus masses without adding any regulator. some members of Spathoglottis could not produce normal growth in the media containing organic component mentioned above. The parts that contacted the media were damaged by phenolic compound or similar substances which interfered with the adsorption of nutrients from a medium. Since orchidaceae is one of the largest family in the plant kingdom, it is expected to have great biodiversity in all aspects. Therefore, physiology of seed germination and seedling growth in expected to be specific for a given group of orchids. Twenty different media are recommended for these purposes.