N. NAGARAJUAVINASH PHULEKAR2023-05-082023-05-082023-02-14Th-13587https://krishikosh.egranth.ac.in/handle/1/5810197144In recent years, endophytes have become increasingly important due to the harmful effects of chemical pesticides. An attempt to exploit endophytes as a potential biocontrol agents against tomato leaf curl virus and its vector whitefly, Bemisia tabaci was made in the present study. A total of 26 endophytes were isolated from plant tissues of tomato, of which 18 were fungi and 8 were bacteria. The endophytes viz., RF4, SF7 and RB3 showed antivector activity against eggs and adults of B. tabaci with decreased egg hatchability respectively by 69.40, 67.56 and 71.10 per cent at 10 days after treatment. However maximum mortality of adult whiteflies was observed at 3 DAT (76.67, 73.33 and 70.00% respectively). The endophytes RF4, SF7 and RB3 were found efficient in production of lytic enzymes. The chitinase activity was observed in RF4 and SF7, while protease and esterase activity was evident in SF7 and RB3. Among the different treatments, T4 [endophyte (seed treatment, seedling dip and spray) followed by virus inoculation] showed the maximum plant height (RF4-95.00, SF7-92.66 and RB3-94.33 cm), T5 [endophyte (seed treatment and spray) followed by virus inoculation] displayed maximum number of branches (RF4-3.66, SF7-3.66 and RB3-4.00) and lowest disease severity was displayed by T4 (RF4-8.33, SF7-16.66 and RB3-25.00%) at 45 DAT. Molecular characterization of endophytic fungi revealed RF4 as Fusarium oxysporum f. sp. lentis and SF7 as Fusarium sp. whereas endophytic bacteria (RB3) as Acinetobacter sp. Finally, RF4 (Fusarium oxysporum f. sp. lentis) showed its potential anti-vector and anti-viral activities.EnglishThesis