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Simple Summary: This is the first study providing important time-specific, age-specific, and reproduction-specific data for managing Spodoptera frugiperda infestations in maize crops using chlorantraniliprole. The application of chlorantraniliprole insecticide suppressed the population of S. frugiperda. The results revealed that fecundity was affected by chlorantraniliprole in the second filial generation, which suggests that the insecticide application during spring will prevent S. frugiperda infestation in maize crops during the autumn season. Fall armyworm [Spodoptera frugiperda (J. E. Smith, 1797)] was first reported in the Americas, then spread to all the continents of the world. Chemical insecticides are frequently employed in managing fall armyworms. These insecticides have various modes of actions and target sites to kill the insects. Chlorantraniliprole is a selective insecticide with a novel mode of action and is used against Lepidopteran, Coleopteran, Isopteran, and Dipteran pests. This study determined chlorantraniliprole's lethal, sub-lethal, and trans-generational effects on two consecutive generations (F0, F1, and F2) of the fall armyworm. Bioassays revealed that chlorantraniliprole exhibited higher toxicity against fall armyworms with a LC50 of 2.781 mg/L after 48 h of exposure. Significant differences were noted in the biological parameters of fall armyworms in all generations. Sub-lethal concentrations of chlorantraniliprole showed prolonged larval and adult durations. The parameters related to the fitness cost in F0 and F1 generations showed non-significant differences. In contrast, the F2 generation showed lower fecundity at lethal (71 eggs/female) and sub-lethal (94 eggs/female) doses of chlorantraniliprole compared to the control (127.5–129.3 eggs/female). Age-stage specific survival rate (Sxj), life expectancy (Exj) and reproductive rate (Vxj) significantly differed among insecticide-treated groups in all generations compared to the control. A comparison of treated and untreated insects over generations indicated substantial differences in demographic parameters such as net reproduction rate (R0), intrinsic rate of increase (r), and mean generation time (T). Several biological and demographic parameters were shown to be negatively impacted by chlorantraniliprole. We conclude that chlorantraniliprole may be utilized to manage fall armyworms with lesser risks. [ABSTRACT FROM AUTHOR]

Sucking pests of cotton (Gossypium hirsutum L.), such as thrips, or Thrips tabaci Lindeman, and jassid, or Amrasca biguttula Ishida, are among the most threatening insect pests to young cotton plants in Pakistan. New chemical insecticides have been trialed to control their damage in commercial fields. Formulations that show good suppression of these pest's populations, while sparing bio-controlling agents, are always preferred for obtaining better crop yield. Six different commercially available insecticides, namely Fountain® (fipronil and imidacloprid), Movento Energy® (spirotetramat and imidacloprid), Oshin® (dinotefuran), Concept Plus® (pyriproxyfen, fenpyroximate, and acephate), Maximal® (nitenpyram), and Radiant® (spinetoram) were evaluated in the present study to shortlist the best available insecticide against targeted pests. Harmful impacts of selected insecticides were also evaluated against naturally occurring predators, such as spiders and green lacewings (Chrysoperla carnea). Radiant® (spinetoram) and Movento Energy®, respectively, were best at controlling thrips (with 61% and 56% mortality, respectively) and jassid (62% and 57% mortality, respectively) populations during 2018 and 2019. Radiant® proved itself as the best option and showed minimal harmful effects on both major arthropod predators of cotton fields i.e., spiders (with 8–9% mortality) and green lacewings (with 12–16% mortality). Movento Energy® also showed comparatively less harmful effects (with 15–18% mortality) towards natural predatory fauna of cotton crops, as compared to other selective insecticides used in the study. The findings of current study suggest that the judicious use of target-oriented insecticides can be an efficient and predator-friendly management module in cotton fields. However, the impact of these chemicals is also depended on their timely application, keeping in consideration the ETL of pests and the population of beneficial arthropods. [ABSTRACT FROM AUTHOR]

Simple Summary: Ecdysteroids have a significant role in insect development and reproduction. Ecdysteroidogensis is regulated by a group of genes known as Halloween genes. We provide experimental evidence that Chilo suppressalis-phantom (Cs-Phm) in rice striped stem borer is a Halloween gene phantom and has important role in specific steps in ecdysteroidogensis. Three lines of experiments were done on typical protein domains of Cs-Phm, RNAi-mediated knockdown of Cs-Phm, and the rescue of larval development in dsRNA-treated groups. The results strongly suggest that Cs-Phm plays a critical role in ecdysteroidogensis in rice striped stem borer. The physiological and biochemical characterization of the "Halloween" genes has fundamental importance in the biosynthesis pathway of ecdysteroids. These genes were found to catalyze the final phases of ecdysteroid biosynthesis from dietary cholesterol to the molting hormone 20-hydroxyecdysone. We report the characterization of the Cs-Phm in a major insect pest in agriculture, the rice striped stem borer, Chilo suppressalis (C. suppressalis). A full-length transcript of Cs-Phm was amplified with an open reading frame (ORF) of 478 amino acids through 5′ and 3′ RACE. Cs-Phm shows five insect-conserved P450 motifs: Helix-C, Helix-I, Helix-K, PERF, and heme-binding motifs. Phylogenetic analysis clearly shows high similarity to Lepidoptera and evolutionary conservation in insects. The relative spatial and temporal transcript profile shows that Cs-Phm is highly expressed in the prothoracic glands and appears throughout the larval development, but with low expression at the start of the larval instar. It seems to peak in 3–4 days and decreases again before the larvae molt. Double-stranded RNA (dsRNA) injection of Cs-Phm at the larval stage efficiently knocked down the target gene and decreased its expression level. The dsRNA-treated group showed significantly decreased ecdysteroid titers, which leads to delayed larval development and higher larval mortality. Negative effects of larval development were rescued by treating 20E in the dsRNA-treated group. Thus, in conclusion, our results suggest that Cs-Phm is functionally conserved in C. suppressalis and encodes functional CYP that contributes to the biogenesis of 20E. [ABSTRACT FROM AUTHOR]

The control of Spodoptera frugiperda, the key invasive pest of maize, is a serious concern due to its biology and the current global restriction on applying synthetic pesticides. Entomopathogenic fungi are considered to be a potential biological control strategy. The pathogenicity of 12 isolates of Beauveria bassiana in the immature stages and feeding efficacy of S. frugiperda were evaluated. The B. bassiana isolates QB-3.45, QB-3.46 and QB-3.428 caused the highest egg mortality rates of 87.3, 82.7 and 79.3%, respectively, when applied at a concentration of 1 × 108 conidia/mL and measured at 7 days post-treatment. Neonate mortality rates of 45.6 to 53.6% were observed with the same isolates. The B. bassiana isolates caused significant cumulative mortality rates ranging from 71.3 to 93.3% at 14 days post-treatment and reduced larval feeding efficacy from 69.4 to 77.8% at 48 h post-treatment. This study supports using the effective B. bassiana isolates as a biological control agent against S. frugiperda. The significant mortality of the eggs and neonatal larvae and the reduction in the feeding efficacy of the second instar larvae of the S. frugiperda that were treated with isolates of B. bassiana supports the application of entomopathogenic fungi as a biocontrol agent for the effective control of the S. frugiperda population. [ABSTRACT FROM AUTHOR]

Simple Summary: Over the past few decades, the ectoparasitic mite Varroa destructor has been a significant threat to managed honey bee (Apis mellifera) colonies worldwide. Many control methods, including application of synthetic acaricides, have been adopted to control the infestation of varroa mites in honey bee colonies. Synthetic acaricides such as coumaphos and fluvalinate are only effective in reducing susceptible mites. Besides, synthetic acaricides pose multiple threats to honey bee colonies and the environment, necessitating their alteration with non-synthetic options. Naturally occurring compounds are considered an essential alternative control measure for varroa mites. Natural acaricides are derived from plants that contain essential oils or organic acids. The current study investigated the efficacy of formic acid, oxalic acid, and thymol in the control of Varroa mites. These soft acaricides were applied at various concentrations/quantities. Formic acid, oxalic acid, and thymol were all effective at lowering mite population levels. Formic acid, oxalic acid, and thymol can be used in an integrated management plan to control varroa mite populations. This scientific-based information can be shared with the beekeeping community of Pakistan and elsewhere, which will be helpful in managing this parasite that often affects honey bee productivity. Honey bees (Apis mellifera) are essential for their products—honey, royal jelly, pollen, propolis and beeswax. They are also indispensable because they support ecosystems with their pollination services. However, the production and functions of honey bees are hindered by the arthropod pest Varroa destructor, which attacks bees through its feeding activities. Efforts to control varroa mites have been made through the development of various synthetic pesticide groups, but have had limited success because the mites developed resistance and some of these pesticides are harmful to bees. Branded pesticides are rarely used in Pakistan, as beekeepers utilize acaricides from unknown sources. There is a need to create awareness of available naturally occurring acaricides that may serve as an alternative to synthetic acaricides. Although some naturally occurring compounds are considered toxic to the environment, the soft acaricides oxalic acid, thymol, and formic acid 65% are usually safe for honey bee colonies and beekeepers, when handled appropriately. The current study investigated the effectiveness of formic acid (10, 15, and 20 mL/hive), oxalic acid (4.2, 3.2, and 2.1%/hive), and thymol (6, 4, and 2 g/hive) in controlling mite infestation. The results indicated that all treatments significantly reduced the mite population (p < 0.05). The average efficacies of oxalic acid at 3.2% (94.84% ± 0.34) and 4.2% (92.68% ± 0.37) were significantly higher than those of the other treatments. The lowest efficacy was recorded in formic acid 65% at 10 mL (54.13%). Overall, the results indicated that soft acaricides—such as oxalic acid at 3.2% and 4.2% concentrations—are very effective at controlling varroa mites and can be used in broodless conditions without side effects. [ABSTRACT FROM AUTHOR]

Simple Summary: Fall armyworm (FAW), primarily endemic to the United States, has posed a severe threat to maize cultivation globally in recent decades. To prevent maize from being harmed by FAW, various control strategies are used, including synthetic pesticides. Synthetic chemicals are still the most effective and widely utilized technique; nonetheless, these chemicals are hazardous to humans, biodiversity, and the environment, necessitating a desperate search for safe and long-term solutions. Entomopathogenic fungi (EPFs) are thought to be an essential alternate control tool for this invasive pest. The goal of this study was to determine the effectiveness of five entomopathogenic fungal isolates (Aspergillus sp. BM-3 and SE-2-1, Cladosporium tenuissimum SE-10, Penicillium citrinum CTD-24, and Beauveria bassiana ZK-5) against immature stages (eggs, neonates, and larvae) and feeding efficacy of first to sixth instar S. frugiperda larvae at 1 × 106, 1 × 107, and 1 × 108 conidia mL−1. Among the five tested fungal isolates, C. tenuissimum SE-10, P. citrinum CTD-24, and B. bassiana ZK-5 showed significant effects on egg mortality and significantly reduced the early third instar feeding efficacy of FAW larvae at the highest concentration level. These potent fungal isolates could be suitable candidates for developing biopesticides in an integrated manner to control the FAW population. By decreasing the hatchability of eggs and reducing the feeding ability of early first to third instar FAW larvae, the findings of this study could assist in managing this invasive pest in China and enhance maize crop output. However, further research is needed to evaluate and validate laboratory outcomes in real-world situations. Maize is a major staple crop in China, and the sustainable productivity of this primary crop has been recently threatened by fall armyworm (FAW), Spodoptera frugiperda, invasion. The five fungal isolates, Aspergillus sp. BM-3 and SE-2-1, Cladosporium tenuissimum SE-10, Penicillium citrinum CTD-24, and Beauveria bassiana ZK-5 were assessed for their efficacy in causing mortality against first to sixth instar eggs and neonate larvae seven days post-treatment, and their effects on the feeding performance of sixth instar S. frugiperda larvae at 48 h post-treatment at three concentrations (1 × 106, 1 × 107, and 1 × 108 conidia mL−1) were also assessed. The six instar S. frugiperda larvae were not susceptible to the five tested fungal isolates. However, B. bassiana ZK-5 caused the highest egg mortality of 40, 70, and 85.6% at 1 × 106, 1 × 107, and 1 × 108 conidia mL−1, respectively, followed by P. citrinum CTD-24 (30.6, 50, and 75.6%) and C. tenuissimum SE-10 (25.6, 40, and 55.6%). In addition, B. bassiana ZK-5 caused the highest neonate mortality of 54.3% at 1 × 108 conidia mL−1. B. bassiana ZK-5 and P. citrinum CTD-24 caused cumulative mortality, including 93.3 and 83.3% mortality of eggs and neonates, respectively, at 1 × 108 conidia mL−1. Furthermore, B. bassiana ZK-5 reduced the feeding efficacy of first to third instar S. frugiperda larvae by 66.7 to 78.6%, while P. citrinum CTD-24 and C. tenuissimum SE-10 reduced larval feeding by 48.3 to 57.1% at 1 × 108 conidia mL−1. However, these fungal isolates were less potent in reducing the feeding activity of fourth to sixth instar S. frugiperda larvae (>46% with B. bassiana at 48 h post-treatment). The tested fungal isolates could play an essential role as microbial biopesticides in suppressing the S. frugiperda population in China after further investigations on their efficacy are obtained in the field. [ABSTRACT FROM AUTHOR]