Mallesha, B . CSWATHI, M2017-08-022017-08-022015-07-09http://krishikosh.egranth.ac.in/handle/1/5810027025Yeast population on phyllosphere of six different tree species of Western Ghats of Hassan district varied from 148.6 to 3004.5 cfu /cm2. Totally 15 different yeast isolates were isolated. Further, these yeast isolates were characterized for utilization of different carbon sources. Out of 15 yeast isolates eight yeast isolates viz., HAP1-I, HAP1-II, HAP1-III, HAP3-I, HAP4-II, HAP5-II, HAP5-III and HAP5-V produced lipase enzyme. They were screened for biocontrol activity against fungal pathogens viz., Fusarium sp., Pythium sp. and Rhizoctonia solani by dual culture method. Seven yeast isolates have shown the biocontrol activity against fungal pathogens. Among these isolates, HAP1-III yeast isolate of Artocarpus hirsutus showed maximum inhibition of all the three fungal pathogens (33.33 % of Fusarium sp., 21.66 % of Pythium sp. and 21.42 % of Rhizoctonia solani). Based on 16S rRNA sequencing HAP1-III yeast isolate was identified as Acremonium kiliense. Five yeast isolates produced relatively higher concentrations of IAA ranging from 0.34-1.44 μg/ml and the maximum IAA was produced by HAP4-I isolate which was identified as Rhodotorula mucilaginosa strain AUMC 7248. All the yeast isolates produced relatively lower concentrations GA in the range of 0.05-0.39 μg/25ml. Greenhouse study revealed that the application of HAP4-I yeast isolate on soybean showed significantly higher plant height (44.23 cm), number of branches (10.67 per plant), number of pods (14.33 per plant), root length (34.87 cm) and plant biomass. A higher level of IAA production in soybean (1.69 μg/g of leaf sample) was observed in plants inoculated with HAP4-I yeast isolate. July, 2015ennullThesis