Determination of minimum threshold temperature and degree day requirements for the development of Spodoptera litura on different host plants

Abstract

The tobacco caterpillar, Spodoptera litura, is a highly destructive pest known for its polyphagous nature, affecting various wild and cultivated plants worldwide. Climatic factors, particularly temperature, greatly influence the development and behavior of S. litura, making it crucial to understand their thermal requirements for effective pest management strategies. Given the considerable economic impact of S. litura infestations on crops such as capsicum, tomato, and castor, there is a pressing need to study the insect's developmental biology and its response to temperature variations. The primary objective of this study is to determine the minimum threshold temperature for the development of S. litura and to calculate the degree day requirements for its development on various host plants, including capsicum, tomato, and castor. The study utilized a linear regression model to calculate the lower developmental threshold and thermal constants for different developmental stages of S. litura on castor, capsicum, and tomato. Results indicated significant variations in the minimum temperature thresholds and thermal constants across host plants, highlighting the influence of host plant species on the developmental biology of S. litura. Additionally, the study observed differences in the thermal requirements of S. litura stages, with higher values observed on capsicum and tomato compared to castor. The findings of this study provide valuable insights into the thermal requirements of S. litura, shedding light on its developmental biology and host plant preferences.