Abstract:

The isolation and culture conditions of endophytes from branch and leaves of Pseudolarix kaempferi Gord. were investigated. Plant materials were sterilized by surface treatment with 75% ethanol, sodium hypochlorite solution and sterilized water. The optimal surface sterilization intensity for isolating endophytes was determined in a progressive decrease way with biological safety cabinet sterilization detection control, washing liquid sterilization detection control and tissue blotting sterilization detection control. The effects of three various media on isolation of endophytes were compared. A short-time sterilization with high concentration sodium hypochlorite solution was more suitable for the isolation of endophytes than a long-time sterilization with low concentration. The growth of fast-growing endophytes was inhibited in a 10% PDA medium supplemented with potassium benzylpenicillin and streptomycin sulfate at 22 ℃ and thus slow-growing ones could obtain some growing space, which was beneficial to maximize the separation of endophytes. The accuracy of isolation of endophytes was guaranteed by the setting of three detection controls.

Key words: medicinal plant, endophyte, isolation, surfacer sterilization, culture method