The fall armyworm (FAW), Spodoptera frugiperda, causes substantial annual agricultural production losses worldwide due to its resistance to many insecticides. Therefore, new insecticides are urgently needed to more effectively control FAW. Cyclosporin A (CsA) is a secondary metabolite of fungi; little is known about its insecticidal activity, especially for the control of FAW. In this study, we demonstrate that CsA shows excellent insecticidal activity (LC₅₀ = 9.69 μg/g) against FAW through significant suppression of calcineurin (CaN) activity, which is a new target for pest control. Combinations of CsA and indoxacarb, emamectin benzoate, or Vip3Aa showed independent or synergistic toxicity against FAW; however, the combination of CsA and chlorantraniliprole showed no toxicity. Sublethal doses of CsA led to decreases in FAW larval and pupal weight, pupation, emergence, mating rates, adult longevity, extended development of FAW larvae and pupae and the pre-oviposition period of adults, and increases in the proportion of pupal malformation. Importantly, CsA treatment reduced FAW ovarian size and female fecundity, which suggests that it has great potential to suppress FAW colony formation. Taken together, these results indicate that CsA has high potential as an insecticide for controlling FAW.

Athetis lepigone Möschler (Lepidoptera: Noctuidae) was first reported in peanut in Liaoning Province in China in 1999. It was first discovered that A. lepigone causes damage to maize crops in Anxing, Hebei Province in China in 2005 (Jiang & Xi 2006). In subsequent yr, an outbreak of this species quickly expanded and severe damage to summer maize crops occurred in the Huang-Huai-Hai Rivers Plain in China over an area of roughly 2.2 million ha in 2011(Shan et al. 2011; Wang et al. 2012). Athetis lepigone now is considered a significant pest of maize in China.

Calosoma chinense Kirby, a generalist predator, consumes a variety of pests. To better understand its predatory behavior and capacity, particularly against Spodoptera frugiperda (J. E. Smith), we identified the field species and investigated the predation capacity of the third-instar larvae and adults of both sexes against the first- to sixth-instar larvae, pupae, and male and female adults of S. frugiperda. The predation preference for different developmental stages of S. frugiperda was further examined. Our results indicated that C. chinense can prey on S. frugiperda in various stages, including larvae and adults, demonstrating robust predatory abilities. Among them, female adults of C. chinense exhibited the strongest predatory ability against first-instar larvae of S. frugiperda, with the highest daily consumption of 38.90 ± 0.79 individuals. The first-instar larvae of C. chinense also showed a certain predatory ability towards S. frugiperda, with a daily consumption of 6.95 ± 0.88 individuals per predator. The predation ability of C. chinense larvae increased with larval growth, especially for the first to third instar of S. frugiperda larvae, and C. chinense female adults had the strongest predation ability, followed by male adults and then third-instar larvae. However, there was no significant difference in predation capacity against fourth- to sixth-instar larvae and male and female adults of S. frugiperda, nor between adults of both sexes and third-instar larvae of C. chinense. The predation choice experiment revealed that the third-instar larvae and male and female adults of C. chinense showed a positive preference for S. frugiperda larvae from the first to fourth instars, while for the fifth- to sixth-instar larvae, they exhibited a negative preference. Overall, C. chinense exhibited a strong ability to prey on S. frugiperda. Our study indicates that C. chinense has the potential for application in the biological control of S. frugiperda.

Calosoma chinense Kirby is a generalist predatory that consumes multiple pests.To better elucidate the behavioral and ecological aspects of this species, we identified the field species and investigated the predation capacity of the third instar larvae and both sexes of adults against the first to six instar larvae, pupae, male and female adults of Spodoptera frugiperda.The predation choice for different developmental stage of S. frugiperda were further conducted. Our results showed that C. sinensis at different developmental stages could prey on S. frugiperda at various stages, especial to larvae and adults, which possess strong predatory abilities. Among them, female adults of C. sinensis exhibited the strongest predatory ability against S. frugiperda 1st instar larvae, with the highest daily consumption of 38.90 ± 0.79 individuals. 1st instar larvae of C. sinensis also showed a certain predatory ability towards S. frugiperda, with the daily consumption of 6.95 ± 0.88 1st instar larvae individuals of S. frugiperda per predator. The predation ability of C. sinensis larvae increased with instar, particularly for 1st to 3rd instar S. frugiperda larvae, C. sinensis female adults have the strongest predation ability, followed by male adults, and then the 3rd instar larvae. However, there was no significant difference in predation capacity between 4th to 6th instar larvae and male and female adults of S. frugiperda, nor between two sexes adults and 3rd instar larvae of C. sinensis. The predation choice experiment revealed that the 3rd instar larvae, male and female adults of C. sinensis showed a positive preference to S. frugiperda larvae from the 1st to 4th instar, while to the 5th to 6th instar exhibited a negative preference. Overall, C. sinensis exhibited a strong ability to prey on S. frugiperda, indicating it have the potential for application in biological control.

To escape or alleviate low temperatures in winter, insects have evolved many behavioral and physiological strategies. The rice pest insect, the purple stem borer, Sesamia inferens (Walker) is currently reported to be expanding their northern distributions and causing damage to summer maize in Xinxiang, China. However, their method of coping with the lower temperature in the new northern breeding area in winter is largely unknown. This paper investigates the overwinter site of S. inferens , and identifies the cold hardiness of larvae collected from a new breeding area in winter and explores a potential distribution based on low temperature threshold and on species distribution model, MaxEnt. The results show that the overwintering location of the S. inferens population is more likely to be underground with increasing latitude and,in the north, with the temperature decreasing, the larvae gradually moved down the corn stalk and drilled completely underground by February 18 ^th . Those who were still above ground were all winterkilled. The cold hardiness test shows the species is a moderate freeze-tolerant one, and Supercooling Points (SCP), Freezing Points (FP) and mortality rate during the middle of winter (January, SCP: −7.653, FP: −6.596) were significantly lower than early winter (October) or late winter (March). Distribution in the new expansion area was predicted and the survival probability area was below N 35° for the Air Lower Lethal Temperature (ALLT ₅₀ ) and below N 40° for the Underground Lower Lethal Temperature (ULLT ₅₀ ), The suitable habitat areas for S. inferens with MaxEnt were also below N 40°. This study suggests the overwinter strategies have led to the colonization of up to a five degree more northerly overwintering latitude. This behavior of S. inferens could help maize producers to propose a control method to increase pest mortality by extracting the maize stubble after harvest.