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Fall armyworm (FAW) Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae), is a global pest causing damage to several crops. However, its management using chemical control is a challenge due to its capacity to evolve resistance to insecticides. After 6 generations of selection with lambda-cyhalothrin, the LC50 for the insecticide-resistant strain (Lambda-Sel) was 486 ppm, higher than that of the field strain (FAW-MUL) (7.5 ppm), susceptible laboratory strain (Lab-PK) (0.46 ppm), and laboratory unselected strain (UNSEL) (5.26 ppm). Laboratory selection with lambda-cyhalothrin increased resistance from 16.3- to 1056.52-fold and 1.43- to 92.4-fold to lambda-cyhalothrin compared to Lab-PK and UNSEL strains, respectively. The selected strain of S. frugiperda (Lambda-Sel) presented low cross-resistance to chlorpyrifos, moderate to deltamethrin and indoxacarb, very low to spinosad, and no cross-resistance to emamectin benzoate. The realized heritability (h 2) of lambda-cyhalothrin resistance in the Lambda-Sel strain was very high (0.88). The reciprocal cross progenies of F1 (Lambda-Sel ♀ × Lab-PK ♂), F1ʹ (Lambda-Sel ♂ × Lab-PK ♀), BC1 (F1 ♀ × Lambda-Sel ♂), and BC2 (F1 ♀ × Lab-PK ♂) showed high resistance ratios of 545.64-, 396.52-, 181.18-, and 146.54-fold, respectively compared to Lab-PK. The degree of dominance values for lambda-cyhalothrin in F1 and F1ʹ indicates incompletely dominant resistance. The difference between observed and expected mortality in backcross populations (BC1 and BC2) revealed a polygenic resistance. In conclusion, the resistance to lambda-cyhalothrin was autosomal, incompletely dominant, and polygenic. These findings provide new insights for insect resistance management strategies to mitigate the occurrence of resistance in this global pest. [ABSTRACT FROM AUTHOR]

Aphids, as notorious pests in wheat cultivation, pose a significant threat to crop yield and quality. The dynamics of aphid populations in wheat fields are intricately linked to various climatic factors, making it crucial to understand and manipulate these interactions for effective pest management. The study was conducted over growing seasons 2022-23, involving the systematic collection of data from wheat fields exposed to varying climatic conditions. These data were then analyzed to investigate the relationship between climatic factors, such as temperature, humidity, and rainfall, and aphid infestations. Additionally, varietal screening was performed to identify wheat cultivars with varying levels of resistance or susceptibility to aphids. The survey findings indicate that the aphid population on various wheat varieties exhibited a range of infestation levels. The findings of this study reveal the complex interplay between climatic factors and aphid population dynamics in wheat fields. Aphid population was maximum (1382.39/trap/week), when maximum and minimum temperature was 28.02 °C and 14.0 °C, respectively with relative humidity 80.83% and 49.62% at 8am and 5pm, respectively. However, for varietal screening of 14 wheat varieties and advance lines, the lowest aphid population was recorded on wheat varieties/lines viz., Arooj-22(4.311), HYT-74(4.378), Dilkash-21(4.433), V-19308(4.778) and HYT-76 (4.789), and these were statistically at par with each other. While maximum aphid population was observed on V-19532 (12.711) followed by V-19317(11.433), V-19559 (10.711), V-19317 (11.433), V-19347 (10.244), Akbar-19 (7.656), and Subhani-21 (6.044). Overall, this manuscript contributes to the body of knowledge on integrated pest management strategies in wheat farming, emphasizing the importance of both surveillance and varietal screening in mitigating aphid-related threats in the face of changing climate patterns. [ABSTRACT FROM AUTHOR]