Interactive Effects of Temperature and Plant Host on the Development Parameters of Spodoptera exigua (Hübner) (Lepidoptera: Noctuidae)

Abstract

This study investigated the effects of different temperatures (15, 20, 25, 27, 30, 35, and 40 °C) on the development rate of Spodoptera exigua (Hübner) eggs, larvae, pupae, and total immatures on plant hosts (soybean, maize, potato, and green pea). The eggs of S. exigua developed successfully at all the tested temperatures, except at 40 °C. The total developmental time (egg-adult) decreased with an increasing temperature from 15 to 35 °C on plant hosts. Stage-specific parameters such as the lower threshold temperature (TH) were determined using linear and nonlinear models (Sharpe-Schoolfield-Ikemoto [SSI]). The lower developmental threshold (LDT) and thermal constant (K) were determined using a linear model. The LDT and K for the total immature stage had respective values of 11.9 °C and 397.27° -day (DD) on soybean, 11.6 °C and 458.34° -day (DD) on maize, 11.2 °C and 446.23° -day (DD) on potato, 10.7 °C and 439.75° -day (DD) on green pea, and 12.2 °C and 355.82° -day (DD) on the artificial diet. The emergence frequency of adult S. exigua over the full range of constant temperatures was simulated using nonlinear developmental rate functions and the Weibull function. This study predicted the spring emergence date in the first to second weeks of June, with approximately five generations for plant hosts. The interaction of temperature and plant host also influenced the development and longevity of the adults. Overall, the findings of this study may be useful for predicting the number of generations, occurrence, population dynamics in crop fields, and management of S. exigua.

Temperature and Host Plant Impacts on the Development of Spodoptera litura (Fabricius) (Lepidoptera: Noctuidae): Linear and Nonlinear Modeling

“…This influence of host plants on development of larvae is also backed by our regression analysis ( Table 5 ). These findings are supported by several previous studies, despite the fact that a coordinated comparison of the findings can be difficult as diverse host plants and natural conditions were utilized in the research [ 6 , 42 , 51 , 101 , 107 , 108 ]. A study by [ 7 ] examining the developmental variables on soybean reported the developmental time of S. litura larva as 93.0 d at 15 °C, which was much longer than in this study.…”

“…In this study, the S. litura eggs could not hatch or complete their development at the higher extreme temperature (40 °C) on either the host plants or the artificial diet. Previous studies have also reported the failure of egg development at extreme temperatures [ 42 , 92 , 93 ]. This abnormal development and the death of the eggs may be attributed to the rapid dehydration and physiological disorders mediated by the induced heat.…”

“…Pest forecasting, management, and pest risk analysis all depend on having access to information about a pest’s development, survival, and reproduction under various environmental conditions. In particular, temperature has a significant impact on the development, population dynamics, distribution, and survival of insect species [ 38 , 39 , 40 , 41 , 42 ], as well as on biological characteristics such as sex ratio [ 43 ], adult longevity, survival, and oviposition [ 44 , 45 , 46 ]. Insect development is very sensitive to temperature changes, and even slight variations in temperature can lead to huge differences in insect phenology [ 41 , 42 , 47 ].…”

“…In particular, temperature has a significant impact on the development, population dynamics, distribution, and survival of insect species [ 38 , 39 , 40 , 41 , 42 ], as well as on biological characteristics such as sex ratio [ 43 ], adult longevity, survival, and oviposition [ 44 , 45 , 46 ]. Insect development is very sensitive to temperature changes, and even slight variations in temperature can lead to huge differences in insect phenology [ 41 , 42 , 47 ]. Predicting the seasonal occurrence and abundance of any pest is essential for the accurate scheduling of control tactics.…”

Three epochs on estimating the parameter values of thermodynamic Sharpe-Schoolfield-Ikemoto (SSI) model describing the relation of temperature and insect development rate

“…There have been 3 recent studies addressing the SSI model (Ahn et al, 2022, Hu et al 2023, Maharjan et al 2023). None of the researchers of these studies used OptimSSI-P; instead, they used a new program called DEoptim.sqrt.SSI-P (named by our group) proposed by Shi et al (2017).…”