Effects of cultural conditions on IAA-productivity of endophytic bacterial strain Klebsiella RE3 isolated from roots of Camellia (Camellia sp)

Relevance. Camellia (in Vietnam, the camellia is called tea with yellow flowers) is not only used as ordinary tea, but also as a medicinal one. Camellia helps prevent tumors, diabetes, reduce cholesterol. Nowadays, research projects with a camellia in Vietnam have mainly focused on the studying of morphological and biological characteristics and selection of camellia. Scientific research in connection with the endophytic microorganisms of camellia was limited. Objective. The purpose of these studies was to assess the effect of cultural conditions and various carbon and nitrogen sources on the IAA producing activity of the strain Klebsiella RE3. Material and methods. The strain Klebsiella RE3 was isolated from the roots of tea shrubs (Camellia sp.) Growing in the gardens of TD-GOLDEN TEAVIET (Tra Hoa vang Tam Däo), located in Quan Ngoai village, Tam Quan municipality, Tam Dao district (Tam Däo), Vinh Phuc Province, Vietnam. Results. The research results showed that strain RE3 synthesizes the maximum IAA after 72 hours of cultivation at pH 7 (13.95 pg / ml), temperature (14.28 pg / ml). Conclusion. Of all the tested carbon and nitrogen sources, D-sorbitol and NH4NO3 are the best carbon and nitrogen sources for strain RE3 with IAA production of 12.9 pg / ml and 11.35 pg / ml, respectively.

Camellia, Klebsiella strain, IAA, productivity, roots, carbon and nitrogen sources, temperature and incubation time