Bijendra KumarSingh, Vivek2021-01-252021-01-252020-12https://krishikosh.egranth.ac.in/handle/1/5810160568Rice (Oryzae sativa L.) is the primary source of food cultivated all around the world. The crop is infected by numerous insects-pests and diseases which cause huge loss in the yield and to reduce these losses farmers apply cocktails of agrochemicals without knowing about the compatibility between the agrochemicals. The present investigation was envisaged to test the compatibility and fungitoxicity between agrochemicals recommended by CIB at particular growth stage against Fusarium fujikuroi, Rhizoctonia solani, Cochliobolus miyabeanus and Xanthomonas oryzae pv. oryzae attacking at vegetative, tillering and panicle emergence stage. The different combinations of insecticides, fungicides, growth regulator and fertilizer were evaluated using poisoned food technique and spectrophotometry in vitro with the objective to reduce the cost involved in separate foliar application of these agrochemicals. During the vegetative phase 34 combinations of 8 agrochemicals were evaluated where mancozeb and isoprothiolane were compatible with all the combinations however, carbendazim was found to be compatible with most of the agrochemicals except chlorpyriphos, chlorantraniliprole and chlorantraniliprole + urea. Interestingly, the addition of urea with the fungicides increased the fungitoxicity against F. fujikuroi urea increasing the fungitoxicity of all the fungicides in the combinations. Most of the combinations were safe except carbendazim + chlorantraniliprole + urea. Of the 62 combinations of 10 agrochemicals evaluated against R. solani and C. miyabeanus attacking during the tillering stage. Carbendazim alone and in combination with other agrochemicals except acetamiprid + urea and thiamethoxam + urea was found to be superior in controlling R solani however, the combination of propineb + carbendazim was found to show synergistic effect against C. miyabeanus with carbendazim showing compatibility in all the combinations except acetamiprid + urea and thiamethoxam + urea. The combination of streptomycin + propineb was found to be highly compatible among the 6 combination against C. miyabeanus during panicle Initiation stage and streptomycin + copper hydroxide, streptomycin + tricyclazole were found to be equally effective and compatible against Xanthomonas oryzae p.v. oryzae. Most of the combinations were safe to use with enhancencement of the fungitoxicity with addition of urea. However, the insecticidal property of these combinations and their efficacy under fields is unknown so evaluation of these properties should be done before recommending them to the farmers.EnglishThesis