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The study was carried out on occurrence of major insect pests of paddy in Guntur District of Andhra Pradesh during rabi 2020-21 in Nagarjuna Sagar Jawahar Canal area in 45 farmers’ fields of five mandals (Vinukonda, Savalyapuram, Ipuru, Nuzendla and Bollapalle). Fortnightly observations on pest population in parallel relation with meteorological parameters revealed the incidence of rice leaf folder (Cnaphaolocrocis medinalis), yellow stem borer (Scirpophaga incertulas), brown planthopper (Nilaparvata lugens), white backed planthopper (Sogatella furcifera), armyworm (Mythimna separata) and gall midge (Orseolia oryzae) in the entire crop growth period among which leaf folder, yellow stem borer and brown planthopper incidence was more evident. The highest pest activity of S. incertulas and C. medinalis was found during first fortnight of November with 3.97% dead hearts and 3.66% leaf damage respectively. Whereas peak population of N. lugens was found in the time of second fortnight of October with 3.59 hoppers/hill. The results of correlation analysis revealed that white ears caused due to S. incertulas showed significant negative correlation with maximum temperature, minimum temperature and rainfall and highly significant positive correlation with minimum temperature, whereas population of N. lugens showed significant negative correlation. KEYWORDS: Seasonal occurrence, yellow stem borer, brown plant hopper, rice leaf folder and abiotic factors |
