Studies on Rhizospheric Mycoflora of Tea （Camellia sinensis） ： In vitro Antagonism with Dominant Bacteria

Species of Trichoderma, Penicillium, Aspergillus and Mucor were found to dominate the rhizosphere of tea bushes in different regions of the Indian Himalayas. The Himachal Himalayas were dominated by Monilia humiscola (45.08%) and Mucor hiemalis (33.11%). In the Uttaranchal Himalayas, Aspergillus clavatum dominated the rhizosphere (54.01%), followed by A. flavous (20.07%). Although the fungal isolates require a mesophillic temperature (15 ℃ to 35 ℃), the tea rhizospheric isolates tolerate a wide range of temperatures (5 ℃ to 45 ℃). When tested for pH tolerance, these fungi showed a wide range (2.0 to 13.0) of pH tolerance under in vitro conditions. Seasonal variations also influenced the colony forming units (cfu) of the rhizospheric fungi, with the maximum forming in November and March, and the minimum in December~February. During this period, the populations of the fungi were found inversely proportional to the bacterial populations. In addition, the dominant bacteria in the tea rhizosphere, i.e., Bacillus subtilis and B. mycoides, showed antagonistic activity against fungal isolates by inhibiting the growth and causing structural abnormalities in mycelium. Tab 5, Ref 13