PLANT GROWTH PROMOTING ENDOPHYTIC FUNGI ISOLATED FROM TEA (CAMELLIA SINENSIS) SHRUBS OF ASSAM, INDIA

The present paper deals with isolation of endophytic fungi from root, stem and leaves of tea (Camellia sinensis) shrubs collected from different tea gardens of Assam, India and evaluation of their plant growth promoting activities in vitro. Out of ten different endophytic fungi isolated the highest IAA (indole acetic acid) activity was observed for Aspergillus niger (36.49+ or -1.17 mu g/ml) followed by Penicillium sclerotiorum (36.35 + or - 2.07 mu g/ml). The highest GA3 activity was exhibited by the fungus Fusarium oxysporum (12.46 + or - 0.84 mu g/ml) followed by P. chrysogenum F1 (10.95 + or - 0.37 mu g/ml). Evaluation of insoluble mineral solubilization activities of endophytic fungi revealed P. sclerotiorum as most efficient phosphate solubilizer (215.98 + or - 0.2 mu g/ml), A. niger as the highest potassium solubilizer (solubilization index 1.74 + or - 0.2) and P. sclerotiorum as the most efficient zinc solubilizer. It was also observed that plant growth promoting activities of the fungal endophytes increased up to a certain period of incubation and thereafter it decreased. As these fungal endophytes were found to be efficient in plant growth promoting activities they may have the potential to develop a biofertilizers consortium.