Abstract

A study was conducted to determine the comparative bio-efficacy of five botanicals viz., neemazal, cedar wood oil, lemon grass oil, eucalyptus oil and camphor oil each with three concentrations against grasshopper (Oxya nitidula) population on rice at MRCFC Khudwani Anantnag during Kharif 2018. The results revealed that the mean live population of O. nitidula per hill ranged from 3.50-4.53 before treatment and ranged from 1.96-2.17 after treatment of botanicals. The data on mean percent reduction of grasshopper, O. nitidula with botanicals revealed that all the treatments were significantly superior over control. Among the botanicals, neemazal, cedar wood oil, lemon grass oil, eucalyptus oil and camphor oil resulted 42.09 and 43.68%, 60.97 and 68.88%, 68.76 and 77.81%; 32.62 and 35.69%, 48.57and 58.92%, 57.79 and 68.62%;  34.65 and 37.30%, 54.41and 62.34%, 62.17and 70.43%; 39.15 and 42.62%, 54.60 and 63.87%, 65.24 and 76.75%; and 33.15 and 34.93%, 48.37 and 55.05%, 56.69 and 67.81% reduction of grasshopper,nitidula population at 1.0, 2.0 and 3.0 ml /L of water in comparison to check (0.00%) 7th and 15th DAT, respectively. The per cent grasshopper damaged leaves per hill ranged from 11.37-14.15% one day before treatment of botanicals and 1.25-5.89, 0.73-5.06 and 0.67-3.83%, 1.66-7.17, 1.35-6.14 and 1.37-4.53%, 1.47-6.88, 1.21-5.64 and 0.95-4.68%, 1.35-6.29, 1.18-4.91 and 0.78-4.43%, and 1.49-7.37, 1.41-6.40 and 1.29-5.47% in neemazal, cedar wood oil, lemon grass oil, eucalyptus oil and camphor oil treated plots at 1.0, 2.0 and 3.0 ml/L of water in comparison to check (3.00, 5.43, 8.37 and 9.28%), respectively. Application of test botanicals had an impact in increasing the grain yield of rice and brought about yield benefits between 43.20 to 655.56 kg/ha over control. The neemazal treatment produced highest grain yield of 6955.56 kg/ha at 3ml/L of water as against 6300.00 kg/ha in untreated control. The overall bio-efficacy of the botanicals evaluated was in the order of Neemazal > Eucalyptus oil > Lemon grass oil > Cedar wood oil > Camphor oil. Hence, botanicals, particularly neemazal, may be recommended for the management of grasshopper (O. nitidula) infesting rice in Kashmir.