Molecular Entomology, 2025, Vol.16, No.1, 11-18 http://emtoscipublisher.com/index.php/me 16 4 Discussion This study observed the developmental cycle, behavioral characteristics, and reproductive ability of Spodoptera litura under artificially controlled environmental conditions, selecting soybean plants as the sole source of feed, and evaluated its survival challenges and adaptation in low to medium humidity environments. The process from pupae to the next generation of pupae takes a total of 45 days, which is longer than the incubation period of Hardik and Dolly (2020) in high humidity environments (65%~75% RH) (approximately 35~38 days). In a low humidity environment (23%), the success rate of Spodoptera litura during pupation and eclosion stages will decrease, making it more prone to difficulties in molting during the pupal stage, increased rates of adult deformities, and even death. This result is consistent with existing research, indicating that humidity is one of the most critical environmental factors affecting the life cycle of Spodoptera litura (Divakara and Manjulakumari, 2015). During the larval rearing process, significant feeding competition and cannibalism were observed among the larger larvae, especially under high-density rearing conditions. This cannibalistic behavior reduced individual survival rates and resulted in fewer pupae and adults in subsequent generations. Thillainayagam et al. (2022) pointed out that Spodoptera litura larvae exhibit "density-dependent aggressiveness," and it is recommended to separate individuals or provide ample space and food under high-density rearing to reduce intraspecific competition. Although soybean was chosen as the natural feed in this experiment, which is practical to some extent, the reproductive efficiency was still lower than that achieved with artificial formulated diets, which have been widely used in recent years. For example, artificial feed based on chickpeas and wheat germ has been shown to increase the average egg-laying capacity of female moths to over 2,500 eggs, whereas the data in this experiment only reached about 132 pupae (10 times the number from the previous generation of 13 pupae) (Gupta et al., 2005). Therefore, in the future, attempts can be made to add protein sources and vitamins to the natural feed, combined with humidity control, to optimize the rearing results. This study also observed the extensive destructive behavior of Spodoptera litura on soybean leaves, pods, and tender stems, confirming its status as a high-risk field pest. Using viral agents, such as nucleopolyhedrovirus (NPV), during the early instar stages has been proven effective, and mating disruption using sex pheromones can also reduce egg counts and population sizes at the source (Yang et al., 2009). On the other hand, the larvae of Spodoptera litura have a high protein content, and after detoxification or heat treatment, they can be used as animal feed or fertilizer, potentially realizing a "pest-to-benefit" resource conversion pathway, as demonstrated by successful experiences in the utilization of insect resources like yellow mealworms and legume pod borers. Acknowledgments This study was conducted at Hainan Institute of Tropical Agricultural Resources. I am deeply grateful to my academic advisor, Professor Fang Xuanjun, for his invaluable guidance during the course of my research and for his strong support in the collection of research materials. Conflict of Interest Disclosure The author affirms that this research was conducted without any commercial or financial relationships that could be construed as a potential conflict of interest. References Abbas A., Wei-Bo Q., Hafeez F., Hasnain A., Shoukat K., Ali J., Xiao F., Liu J., Ghramh H., Khan K., Ullah F., and Ri-Zhao C., 2025, Unveiling the feeding response of Spodoptera litura to natural host and artificial diet, Entomologia Experimentalis et Applicata, 173(3): 218-231. https://doi.org/10.1111/eea.13537 Baoqia L., 2015, Species and occurrence of lepidopteran pests infesting cucurbits and vegetables in Hainan, Chinese Journal of Tropical Agriculture, 2015: 87453008.
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