Antifungal pathogen activities and growth promotion of endophytic actinomycetes on brassica seedling

• Main Authors: Kunasakdakul,K., Suwitchayanon,P., Phuakjaiphaoe,C.
• Format: Article
• Published: Chiang Mai University 2015
• Subjects: Multidisciplinary
• Online Access: http://www.scopus.com/inward/record.url?partnerID=HzOxMe3b&scp=84872236656&origin=inward; http://cmuir.cmu.ac.th/handle/6653943832/38043
• Institution: Chiang Mai University

Vegetable plants with disease symptoms were collected for isolation, identification and pathogenicity testing of the causing fungal pathogens. They were Alternaria brassicicola for Chinese kale alternaria leaf spot, Alternaria brassicae for leaf spot of cabbage, Sclerotium sp. for root rot of Chinese kale, Choanephora sp. for wet rot of Chinese kale and Fusarium sp. for wilt of lettuce. Eleven isolates of endophytic actinomycetes from the herbal plants as follows; KAE1, GAL1, GLI1, BER1, NEE1, KMI1, FIT2, FIT3 and FIT5 isolates of Streptomycete sp, HOU1 isolate of Nocardioides and LEM1 isolate of Nocardiopsis were used for testing of their abilities to inhibit the growth of the fungal pathogens mentioned above by dual culture technique. Their effects on root length, plant height and fresh weight of brassica seedling were also evaluated. We found that among the 11 isolates tested, KAE1, GAL1 and LEM1 showed broad spectrum to control vegetable pathogens. Under laboratory testing, these three endophytic actinomycetes had high inhibitory efficiency against Fusarium, soil borne pathogen, and two air borne pathogens, Choanephora and A. brassicae. Only one isolate, FIT5 showed fairly high inhibitory against all the tested fungal pathogens. HOU1 isolate was the only one isolate having significant improvement on root length of brassica seedling as compared to uninoculated control and this isolate was the best and significantly better than the other isolates except FIT5. HOU1 also showed the highest inhibitory percentage on Sclerotium, soil borne pathogen.