Biological control of root knot nematode of rice using native isolates of Trichoderma

Abstract

Rice crop is affected by many fungal, bacterial, viral and nematode diseases. Among the nematode, rice root knot nematode (M. graminicola) is considered as a major problem in rainfed upland and low land rice. Rice root knot nematode is widely distributed in many states of India such as Kerala, Uttar Pradesh, West Bengal, Punjab, Haryana etc. In rice wheat cropping system of western U. P. this nematode is causing considerable loss in Basmati rice production. In present study, 34 native isolates of Trichoderma were isolated from soil and screened against rice root knot nematode under pot condition. The observation on number of galls/plant and plant growth parameters were recorded. On the basis of performance one isolate S32 was selected for further study to test the performance this isolate in the management of rice root knot nematode. Culture filtrate of Trichoderma isolate S32 was tested at different concentration (100, 75, 50, 25, 10 and 5%) against larval mortality and egg hatching of M. graminicola and observation were recorded after 24, 48 and 72 hours of inoculation. Maximum larvae mortality 30%, 45% and 80% at 24, 48 and 72 hours of inoculation was recorded in Trichoderma isolate S32 @ 100% concentration respectively. Minimum egg hatching 1.67, 2.33 and 3.67 recorded at 24, 48 and 72 hours of inoculation observed @ 100 % concentration respectively. Trichoderma was applied in the form of seed treatment in different dosses, whereas at 30 days minimum (2.67 and 2.0) galls/plant and maximum plant height (22.33 and 20.00 cm) were recorded in seed treatment with Trichoderma @ 10 g/kg of seed in both experimental years. At 60 days minimum (3.0 and 4.0) galls/plant and maximum plant height (44.78 and 42.55 cm) were recorded in Trichoderma @ 10 g/kg seed during both experimental years. In case of soil application, minimum (1.55 and 1.33) galls/plant and maximum plant height (27.00 and 26.66 cm) were recorded in soil application of Trichoderma @ 10 g/Kg soil in both experimental years. Trichoderma isolate S32 was applied in combination with different chemical i.e., carbofuron, phorate and organic amendments i.e., neem cake, poultry manure and FYM. Minimum (3.33 and 3.00) galls/plant and minimum nematode population 0.67and 1.0 /g soil were recorded in Trichoderma @ 10 g + carbofuron @ 0.3 g/kg soil in both experimental years. Trichoderma isolate S32 was applied in combination with different dosses of vermicompost (5 g, 10 g, 15 g, 20 g, 25 g, and 30 g). At 30 days after sowing minimum (2.67 and 1.00) galls/plant and maximum plant height (14.00 and13.33 cm) were recorded in Trichoderma @ 10 g + vermicompost @ 30 g/kg of soil during year 2019 2020 and 2020 2021, respectively. At 60 days after sowing, minimum (4.00 and 2.00) galls/plant and maximum plant height (39.55 and 40.44 cm) were recorded in Trichoderma @ 10 g + vermicompost @ 30 g/kg soil during year 2019 2020 and 2020 2021, respectively. Another experiment was also conducted in pot condition in the form of drenching methods with different doses (1 g, 2 g, 3 g, 4 g, 5 g, 6 g, 7 g, 8 g, 9 g and 10 g) of Trichoderma isolate S32, minimum (0.67 and 1.00) galls/plant and minimum (0.33 and 0.33) nemetode population were recorded in Trichoderma @ 10 g/liter water during year 2019 2020 and 2020 2021, respectively. On the basis of present study, it has been observed that Trichoderma spp. (isolate S32) was fou nd potential bio agent for the management of rice root knot nematode. Therefore, this may be recommended for the management of rice root knot nematode particularly in rice.