Effects of Indigenous Plant Extracts on Incidence of Stem Borer , Scirpophaga Incertulas (Walker) and Leaf Folder, Cnaphalocrosis Medinalis (Guenee) in Basmati Rice

Abstract

The present investigation was carried out in randomized block design with three replications during Kharif, 2019 at Crop Research Centre of Sardar Vallabh Bhai Patel University of Agri. & Tech., Meerut. The first incidence of rice stem borer was recorded on fourth week of June and reached its peak (9.11 per cent dead hearts) during fourth week of August when average temperature and relative humidity were 320C and 65.6 per cent, respectively. The first incidence of rice leaf folder was recorded on first week of July and reached a maximum level at the third week of September when mean temperature and relative humidity were 28.40C and 87 per cent, respectively. There was positive correlation of dead hearts with evening RH, morning RH, minimum and maximum temperature. The correlation relationship of relative humidity, minimum temperature and maximum temperature is negative with per cent white ears. The correlation of rice leaf folder was positive with minimum temperature, RH and rainfall and negative with maximum temperature. Efficacy of different plant extracts viz., Cow urine + Azadirachta indica ,Cow urine + Melia azedarach ,Cow urine + Lantana camara ,Cow urine +Jatropha gossypiflora ,Cow urine + Eucalyptus oblique ,Cow urine + Cannabis sativa and Neemoz (Azadirachtin 300 ppm) against rice stem borer and leaf folder revealed that Neemoz @ 2500 ml/ha was most effective treatment in reducing the infestation of both the insects followed by Cow urine + Melia azedarach @ 7500ml/ha. The Cow urine + Cannabis sativa @ 7500 ml/ha was recorded least effective. Cow urine + Cannabis sativa @ 7500 ml/ha was found most safe to spider population followed by Cow urine + Lantana camara @ 7500 ml/ha while Neemoz @ 2500 ml/ha was least safe to spider population. The maximum yield (37.30 q/ha) was obtained in Neemoz treated plots. The minimum yield (31.20 q/ha) was obtained in Cow urine + Lantana camara @ 7500 ml/ha treated plots. The highest cost benefit ratio (1:21.44) was obtained from Cow urine + Melia azadirah @ 7500 ml /ha treated plots. . The lowest cost benefit ratio (1:7.19) was obtained from Neemoz treated plots.