UTTAR PRADESH JOURNAL OF ZOOLOGY

The present study was conducted to determine the seasonal incidence of D. citri on Kinnow mandarin and its relationship with prevailing abiotic factors under the agro-climatic conditions of the Bundelkhand region in Banda district, Uttar Pradesh, India. The experiment was conducted at the College of Horticulture, Banda University of Agriculture and Technology, Banda, during two consecutive years, 2024-25 and 2025-26. The study aimed to determine the seasonal prevalence of D. citri on Kinnow mandarin and its relationship with prevailing climatic factors in the Bundelkhand region. Weekly observations were recorded on five randomly selected Kinnow trees, with five twigs sampled from each direction on each tree, and the number of nymphs per twig was calculated. The nymphal population of D. citri ranged from 0.00 to 37.10 nymphs twig^-1 in 2024 and from 0.00 to 39.50 nymphs twig^-1 in 2025. Nymphal incidence first appeared during the 8^th and 9^th SMWs of February, with 0.90 and 1.25 nymphs twig^-1, respectively, and peak incidence was recorded in the 42^nd SMW, with 37.10 and 39.50 nymphs twig^-1 during 2024-25 and 2025-26, respectively. Correlation analysis indicated significant positive associations between nymphal population and maximum temperature (r = 0.435*) and minimum temperature (r = 0.469*) in 2024; relative humidity also showed a significant positive association (r = 0.425*). In 2025, significant positive correlations were observed with maximum temperature (r = 0.457*), minimum temperature (r = 0.453*), and relative humidity (r = 0.420*). Rainfall showed a negative but non-significant association with psyllid population in both 2024 (r = -0.253^NS) and 2025 (r = -0.038^NS).