Seasonal Abundance and Population Dynamics of Aphis gossypii on Cotton in Relation to Temperature and Relative Humidity

Abstract

The cotton aphid, Aphis gossypii, is a major sap-sucking pest responsible for significant yield losses in cotton production systems worldwide. Its population dynamics are strongly influenced by prevailing environmental conditions, particularly temperature and relative humidity. The present study investigated the seasonal abundance and population fluctuations of A. gossypii on cotton in relation to abiotic factors under field conditions. Regular field sampling was conducted throughout the cropping season to monitor aphid density on cotton plants at different growth stages. Concurrent meteorological data, including temperature and relative humidity, were recorded to analyze their relationship with pest incidence. The results revealed distinct seasonal variation in aphid populations, with peak abundance occurring during warm and moderately humid conditions favorable for rapid reproduction and population buildup. Both very high temperatures and low relative humidity were associated with a decline in aphid density due to reduced survival and reproductive efficiency. Statistical analysis indicated a strong positive correlation between moderate temperature ranges and aphid population growth, while relative humidity showed a significant influence on nymphal development and adult longevity. Early crop growth stages were identified as more susceptible to aphid infestation due to tender foliage and favorable microclimatic conditions. The study highlights the importance of environmental factors in regulating the population dynamics of A. gossypii in cotton ecosystems. These findings provide valuable insights for developing weather-based forecasting models and improving integrated pest management strategies aimed at timely intervention and sustainable aphid control in cotton production systems.