INFLUENCE OF WEATHER PARAMETERS ON POPULATION DYNAMICS OF MAJOR INSECT PESTS OF BASMATI RICE Ankur Prakash Verma 1 *, Hem Singh 1 , Gaje Singh 1 , D. V. Singh 1 , Ramesh Singh 2 and Akash Tomar 3 1 Department of Entomology, Sardar Vallabhbhai Patel University of Agriculture & Technology, Meerut - 250 110, India. 2 Department of Plant Pathology, Sardar Vallabhbhai Patel University of Agriculture & Technology, Meerut - 250 110, India. 3 Department of Recombination Techniques, S. V. Patel University of Agriculture & Technology, Meerut - 250 110, India. *e-mail: ankur.pv@gmail.com (Received 28 March 2021, Revised 23 May 2021, Accepted 2 June 2021) ABSTRACT : The present investigation was carried out at the Crop Research Centre of Sardar Vallabhbhai Patel University of Agriculture & Technology, Meerut during the Kharif season, 2019 and 2020 to assess the effect of weather parameters on the population dynamics of major insect pests of basmati rice. Results revealed that yellow stem borer, Scirpophaga incertulas Walker and leaf folder, Cnaphalocrocis medinalis Guenee were highly notorious during both seasons. During Kharif season 2019, the highest population of yellow stem borer and leaf folder was observed around the 32 nd and 34 th meteorological standard weeks (MSW) with an infestation of 10.51 and 8.04 %, respectively. During Kharif 2020, the maximum infestation by yellow stem borer was found during the 33 rd MSW with 9.59 % dead hearts, while infestation by leaf folder was highest during the 34 th MSW with 7.86 % leaf damage. Correlation studies revealed that infestation by yellow stem borer was non-significant and positively correlated with minimum temperature and average relative humidity while non-significant and negative with maximum temperature and rainfall. The infestation by leaf folder showed a significant positive correlation with the minimum temperature, while a non-significant and positive with average relative humidity. Maximum temperature and rainfall showed a non-significant negative correlation. Key words : Basmati rice, correlation, leaf folder, weather parameters, yellow stem borer. How to cite : Ankur Prakash Verma, Hem Singh, Gaje Singh, D. V. Singh, Ramesh Singh and Akash Tomar (2021) Influence of weather parameters on population dynamics of major insect pests of basmati rice. J. Exp. Zool. India 24, 1275-1280. DocID: https://connectjournals.com/03895.2021.24.1275 INTRODUCTION Rice is the world’s most important food crop and is the staple food for 50 % of the world’s population (Barrion et al, 2007). Basmati rice is a special group of rice cultivars having long grain size, good quality and aroma. India is considered the largest exporter of Basmati Rice in the world. Basmati rice is grown mainly in the Himalayan regions, Haryana, Punjab and Western regions of Uttar Pradesh. The crop is attacked by several insect pests from nursery to harvest, which cause severe yield loss in one region of the country or another (Asghar et al, 2009). The major insect pests that attack the crop includes yellow stem borer, Scripophaga incertulas (Walker), leaf folder, Cnaphalocrocis medinalis (Guenee), white- backed planthopper, Sogatella furcifera (Horvath), brown planthopper, Nilaparvata lugens (Stal.), gundhi bug, Leptocorisa acuta (Thunberg) and others. Among these yellow stem borer and leaf folder are the most notorious pests causing significant losses (Sachan et al, 2006; Dhaliwal et al, 2010 and Saini et al, 2015). Abiotic factors are believed to greatly influence the pest population (Singh et al, 2009). Climatic factors such as temperature, rainfall and relative humidity greatly influence the outbreak of the insect population (Heong et al, 2007; Siswanto et al, 2008). Population dynamics of yellow stem borer and leaf folder like any other species are thus liable to fluctuate according to the dynamic condition of its environment (Khaliq et al, 2014). Quantification of important factors leading to change in pest scenario due to environmental conditions is needed to reliably forecast insect populations. Besides, knowledge of the seasonal abundance and population build J. Exp. Zool. India Vol. 24, No. 2, pp. 1275-1280, 2021 www.connectjournals.com/jez ISSN 0972-0030 DocID: https://connectjournals.com/03895.2021.24.1275 eISSN 0976-1780