Potentiality of native Trichoderma harzianum in controlling damping off and foot rot of chilli and its viability in different storage conditions

Abstract

The potentiality of native Trichoderma harzianum against damping off and foot rot of chilli caused by Sclerotium rolfsii and Fusarium oxysporum, respectively as well as its shelf life as formulated product in different storage conditions was evaluated. In dual culture, native T. harzianum inhibited the mycelial growth of S. rolfsii by 60.56% and F. oxysporum by 81.67% over control. In green house conditions, soil received both formulated T. harzianum (20 g/kg of soil) and T. harzianum suspension (2.45×107 CFU/mL) resulted reduced severity of damping off by 81.80% and foot rot by 84.61% over control; however, the combined application of both the treatments was also resulted the highest seed germination (70.28%). The formulated T. harzianum (@ 50 g/polyethylene bags) was stored in table top, wooden shelve, tin container, wooden locker at room temperature, and in refrigerator at 4 °C. The spore density was constantly increased from the initial amount (22×106 CFU/g) in all the treatments and reached the peak after 45 days in wooden locker (73×106 CFU/g) and tin container (66×106 CFU/g) where, it reached the peak at 60 days in table top (126.3×106 CFU/g), wooden shelve (109×106 CFU/g) and refrigerator (89.67×106 CFU/g). However, the maximum population density (126.3×106 CFU/g) was observed in table top storage at 60 days which also remained highest even after 120 days (51.67×106 CFU/g) in comparison to other treatments. The findings of the study revealed that the native T. harzianum can be exploited as an effective bio-control agent for the successful disease control program in chilli as it showed extended shelf life in common storage facility.