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The fall armyworm, Spodoptera frugiperda (Noctuidae; Lepidoptera), is a serious threat to food security as it has the potential to feed on over 353 plant species. To control this insect pest, endophytic colonization of entomopathogenic fungi (EPF) in plants is being considered as a safer and more effective alternative. This study evaluated the efficacy of two EPFs, Beauveria bassiana and Metarhizium anisopliae, for endophytic colonization using foliar spray and seed treatment methods on maize plants, and their impact on the survival, development, and fecundity of S. frugiperda. Both EPF effectively colonized the maize plants with foliar spray and seed treatment methods, resulting in 72–80% and 50–60% colonization rates, respectively, 14 days after inoculation. The EPF negatively impacted the development and fecundity of S. frugiperda. Larvae feeding on EPF-inoculated leaves had slower development (21.21 d for M. anisopliae and 20.64 d for B. bassiana) than the control treatment (20.27 d). The fecundity rate was also significantly reduced to 260.0–290.1 eggs/female with both EPF applications compared with the control treatment (435.6 eggs/female). Age-stage-specific parameters showed lower fecundity, life expectancy, and survival of S. frugiperda when they fed on both EPF-inoculated leaves compared with untreated leaves. Furthermore, both EPFs had a significant effect on population parameters such as intrinsic (r = 0.127 d−1 for B. bassiana, and r = 0.125 d−1 for M. anisopliae) and finite rate (λ = 1.135 d−1 for B. bassiana, and λ = 1.1333 d−1 for M. anisopliae) of S. frugiperda compared with the control (r = 0.133 d−1 and λ = 1.146 d−1). These findings suggest that EPF can be effectively used for the endophytic colonization of maize plants to control S. frugiperda. Therefore, these EPFs should be integrated into pest management programs for this pest. [ABSTRACT FROM AUTHOR]

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Simple Summary: Fall armyworm, Spodoptera frugiperda (Lepidoptera: Noctuidae), is an economically important insect pest of corn crops globally. However, some other host plants on which this pest can successfully complete its generation have also been reported. Our main objective was to study the biology of fall armyworm feeding on maize, sorghum, wheat, and rice. Our overall findings show that maize is the most preferred host plant; however, the pest completed the life cycle successfully on sorghum and wheat. The survival rate was low when rice leaves were provided to larvae as diet, suggesting that rice is a non-preferred host plant. Fall armyworm, Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae), is a polyphagous insect pest of many important crops. To evaluate the influence of host plants on the biology and survival of the Pakistani population of S. frugiperda, we examined life table parameters of S. frugiperda raised on maize, sorghum, wheat, and rice. The development rate was significantly higher on the maize crop than on the other three host plants. Different larval diets affected development time and fecundity. S. frugiperda attained the fastest larval development (16 days) on maize and the slowest development (32.74 days) on rice. Adult females from maize-fed larvae laid 1088 eggs/female, those from sorghum-fed larvae laid 591.6 eggs/female, those from wheat-fed larvae laid 435.6 eggs/female, and those from rice-fed larvae laid 49.6 eggs/female. Age stage-specific parameters also indicated the higher fecundity, higher life expectancy, and higher survival of S. frugiperda on maize plants than on the other three hosts. Larval diets had a significant varying effect on the finite and intrinsic increase rates, reflecting that maize was the most suitable diet. The findings of the present study are useful for predicting population dynamics especially in areas cultivating Poaceae crops, except maize, to develop sustainable integrated pest management strategies for this pest. [ABSTRACT FROM AUTHOR]

Fall armyworm (FAW), Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae) is a destructive insect pest of various economic crops. This species was first reported in Pakistan during 2019, and is now an emerging threat to Pakistan's Agriculture. The main objective of the study was to evaluate the efficacy of a synthetic insecticide Chlorantraniliprole in comparison to different concentrations of single botanical, i.e., neem leaf extract @ (50 ppm and 100 ppm) against FAW larvae in maize. Our findings showed a significant effect (P < 0.001) of these chemicals on the mortality and consumption rate of FAW larvae. Results show that mortality increased in all treatments with time. Recommended dose of chlorantraniliprole (50 ml/100 litre water) insecticide showed 71.0% mortality of FAW on 5th day, which increased up to 82.0% on the 7th day after application of treatments. No significant (P > 0.05) difference in larval mortality was observed for chlorantraniliprole (recommended dose) and neem at 100ppm on the 5th and 7th day after application. Higher concentration (100ppm) of neem showed 59.0% mortality of FAW larvae on 5th and 72.0% on the seventh day of application. Chlorantraniliprole reduced 62.9% food consumption on the 5th day and 71.9% on the 7th day, while 43.5% on the 5th day and 51.6% on the 7th day reduction in food consumption occurred at 100 ppm when compared to the control group. While using 50ppm concentration of neem extract, 20.90% and 27.35% consumption rate was reduced at 5th and 7th day respectively. Our findings suggest chlorantraniliprole as an effective insecticide to control FAW larvae in maize crop; however, neem extract at 100 ppm concentration also performed well against this pest. As botanicals have less harmful to humans and the environment than synthetic insecticides, neem leaf extract can be used in integrated pest management programs of FAW. [ABSTRACT FROM AUTHOR]

Fall armyworm, Spodoptera frugiperda (JE Smith) (Lepidoptera: Noctuidae), is a destructive pest of a wide array of agricultural and horticultural crops worldwide. This in vitro research assessed the combined effect of methanolic extracts of indigenous flora of Soone Valley (Khushab, Pakistan) and nine commonly used synthetic insecticides against 3rd instar larvae of S. frugiperda using the leaf-dip bioassay method. Toxicity bioassays with twelve plant extracts revealed that the extracts of Withania somnifera (L.) Dunal, Sophora mollis (Royle) Baker and Rhazya stricta Decne. were the most effective, exhibiting minimum LC50 and LT50 values. Bioassays with synthetic insecticides revealed a significantly higher mortality of S. frugiperda larvae by emamectin benzoate (45%), chlorpyrifos (40%) and chlorantraniliprole (38%). Further bioassays with 10 binary combinations of these most effective botanical and synthetic insecticides showed that seven pesticidal combinations exhibited synergistic toxicity, and three combinations comprising emamectin benzoate exhibited an additive effect on the mortality of S. frugiperda larvae. GC–MS analyses of methanolic extracts of W. somnifera, S. mollis and R. stricta revealed 1,2,4-trimethyl-benzene and 3,5-dimethyl-octane, 1-ethyl-2-methyl-benzene, and 1-monolinoleoylglycerol trimethylsilyl ether, decane, and lupeol as major bioconstituents, respectively. Our results demonstrated that combining botanicals with synthetic insecticides can synergize their toxicity against S. frugiperda larvae, suggesting their potential incorporation into future IPM programs against S. frugiperda and other lepidopterous pests. [ABSTRACT FROM AUTHOR]