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The fall armyworm, Spodoptera frugiperda (J. E. Smith), identified as an invasive pest worldwide, has severely threatened agricultural production and food security in India. To formulate eco‐friendly integrated pest management strategies for S. frugiperda in its new invasive habitat, the basic knowledge about demographic parameters and damage potential of this pest is crucial. The effects of five host crops viz. maize (Zea mays L.), popcorn (Zea mays everta Sturt), sweet corn (Zea mays saccharata Sturt), sorghum (Sorghum bicolor (L.)) and soybean (Glycine max (L.) Merr.) on the development and food consumption of S. frugiperda were examined. Population projection curves based on life table and consumption rates were drawn on different hosts using computer simulation.The pre‐adult development of S. frugiperda was fastest on popcorn (28.02 days), maize (28.04 days) and sweet corn (28.31 days) but slowest on soybean (34.83 days). The highest net reproductive rate, intrinsic rate of increase and finite rate of increase were observed on maize. The feeding potential of S. frugiperda was also highest on maize. The maximum consumption of the sixth larval instar was observed on maize (19470.47 mm2) while lowest on soybean (9033.67 mm2). In the simulation period of 90 days, the fastest growth of S. frugiperda was expected on maize, popcorn and sweet corn while the slowest on soybean.High larval and pupal survival recorded on the non‐maize hosts (sorghum and soybean) reflects that fall armyworm could be an obstacle in their production as well as in the success of maize‐soybean intercropping system. Simulations based on age‐stage, two‐sex life table could be helpful in predicting the most appropriate time for the pesticide application as well as augmentative releases of egg and larval parasitoids for the control of fall armyworm. [ABSTRACT FROM AUTHOR]

Phytoseiids are an essential group of predators that feed on phytophagous mites. Studies on the detrimental impacts of plant protection chemicals on phytoseiids are crucial for their successful utilization as biocontrol agents. In the present study, the toxicity and side effects of fungicides on the predatory mite Neoseiulus longispinosus (Evans) (Acari: Phytoseiidae) were examined fed on Tetranychus urticae Koch (Acari: Tetranychidae) in tomato under laboratory conditions. Gravid females of N. longispinosus were exposed to fungicides using the leaf dip method for 48 hours. Results showed that the fungicide metalaxyl + mancozeb caused the highest mortality of 60%, followed by mancozeb (52.50%), copper oxychloride (35%), and thiophanate methyl (17.50%). Additionally, residual toxicity from metalaxyl + mancozeb and mancozeb treatments significantly affected the biological and life table parameters of the predatory mite. However, the effects of the other two fungicides were moderate to negligible, implying that the application of metalaxyl + mancozeb and mancozeb could negatively impact the biological performance of N. longispinosus in tomato fields. [ABSTRACT FROM AUTHOR]

The HIV capsid (CA) protein is a promising target for anti‐AIDS treatment due to its critical involvement in viral replication. Herein, we utilized the well‐documented CA inhibitor PF74 as our lead compound and designed a series of low‐molecular‐weight phenylalanine derivatives. Among them, compound 7t exhibited remarkable antiviral activity with a high selection index (EC50 = 0.040 µM, SI = 2815), surpassing that of PF74 (EC50 = 0.50 µM, SI = 258). Furthermore, when evaluated against the HIV‐2 strain, 7t (EC50 = 0.13 µM) demonstrated approximately 14‐fold higher potency than that of PF74 (EC50 = 1.76 µM). Insights obtained from surface plasmon resonance (SPR) revealed that 7t exhibited stronger target affinity to the CA hexamer and monomer in comparison to PF74. The potential interactions between 7t and the HIV‐1 CA were further elucidated using molecular docking and molecular dynamics simulations, providing a plausible explanation for the enhanced target affinity with 7t over PF74. Moreover, the metabolic stability assay demonstrated that 7t (T1/2 = 77.0 min) significantly outperforms PF74 (T1/2 = 0.7 min) in human liver microsome, exhibiting an improvement factor of 110‐fold. In conclusion, 7t emerges as a promising drug candidate warranting further investigation. [ABSTRACT FROM AUTHOR]

AbstractLeopard moth Zeuzera multistrigata (Lepidoptera: Cossidae) is a xylophagous insect whose larval stages are cryptic woodborers in apple and many other horticultural and forestry crops. The present study was carried out to test effectiveness of some biocontrol agents along with most effective pesticide against this pest on apple (cv. Royal Delicious) in Himachal Pradesh, India, for three consecutive years by injecting biocontrol agents/chemicals directly into galleries made by pest larvae. Investigations were conducted to observe the effect of Beauveria bassiana, Metarhizium anisopliae, Steinernemma feltiae, Heterorhabditis bacteriophora and azadirachtin along with a synthetic pesticide chlorpyriphos. The application of chlorpyriphos (0.04%) caused a 100%%larval mortality, whereas among the biocontrol agents H. bacteriophora (5000 IJs/gallery) exhibited the highest mortality of 66.7 to 80.0%% during these three years, which was significantly at par with application of azadirachtin (Neem baan) 1500 ppm @ 2 ml/Litre and S. feltiae @ 5000 IJs/gallery. The lowest mortality (33.3%) was observed with B. bassiana (5 g/Litre) for the first two years and with M. anisopliae (5 g/L) in the third year i.e. 40.0%. Application of entomopathogenic nematode H. bacteriophora (5000 IJs/gallery) is proven to be best among all biocontrol agents. [ABSTRACT FROM AUTHOR]

Many insect pests, including the brown planthopper (BPH), undergo windborne migration that is challenging to observe and track. It remains controversial about their migration patterns and largely unknown regarding the underlying genetic basis. By analyzing 360 whole genomes from around the globe, we clarify the genetic sources of worldwide BPHs and illuminate a landscape of BPH migration showing that East Asian populations perform closed-circuit journeys between Indochina and the Far East, while populations of Malay Archipelago and South Asia undergo one-way migration to Indochina. We further find round-trip migration accelerates population differentiation, with highly diverged regions enriching in a gene desert chromosome that is simultaneously the speciation hotspot between BPH and related species. This study not only shows the power of applying genomic approaches to demystify the migration in windborne migrants but also enhances our understanding of how seasonal movements affect speciation and evolution in insects. [ABSTRACT FROM AUTHOR]

Tobacco, being an established risk factor for significant mortality and morbidity, causes over 7 million annual deaths globally. India is a country with over 270 million active tobacco users. On the one hand, although the willingness to quit amongst tobacco users is as high as 55.4%, the actual quit rates translate to less than 20%. Taking a cue from the economic principle of commitment and consistency, paying a nominal fee can serve as a form of public commitment and motivation to decrease the dropout rate amongst those committed to quitting. This study uses contingent valuation assessment to determine the willingness to pay (WTP) values for an effective tobacco cessation service across individuals with different socio-demographic characteristics. A cross-sectional observational study with multistage cluster sampling in Rajasthan was conducted to recruit 360 active tobacco users from 8 districts. Q-Q plots were used to determine the non-parametric distribution, and statistical differences between median WTP values were compared using Mann-Whitney U and Kruskal-Wallis H tests, considering a p-value less than 0.05 to be statistically significant. The majority of participants were males (57.78%) between the ages of 26 and 35 (40.28%), married (82.50%), and with children (65.83%), with an annual income between USD 7500-10,000 (23.61%) and graduate-level education (40.56%). Exclusive smokers formed the majority of the cohort (48.06%), and 50.83% were willing to quit as well as willing to pay for cessation. Median WTP values were maximum for males (USD 54.05; p<0.05), age group 26-35 years (USD 54.05; p<0.05), post-graduates (USD 81.08; p<0.05), and annual income above USD 20,000 (USD 121.62; p<0.05). Weak positive and significant correlations were observed between WTP and annual spending on tobacco, annual spending on health, and annual income. The study emphasizes the critical importance of early-age interventions for effective tobacco cessation prior to transitioning into dependency, resulting in reduced financial parity for availing health services. These are the first such WTP values from the Southeast Asian region, tailored for different population subsets, specifically for tobacco cessation. Our findings contribute to the growing body of evidence to support innovative approaches to enhance tobacco cessation efforts through financial commitments.

The fall armyworm (FAW), Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae) is a highly destructive polyphagous pest that primarily damages maize. Maize is considered a most versatile crop for growing intercrops due to the wide row it needs. Maize-pea intercropping is preferred by small and marginal farmers worldwide due to various advantages including higher yield and improved economic benefits. However, the success of this intercropping system may be hampered if pea could sustain the FAW population. Thus, to clarify the fitness and potential effect of S. frugiperda on pea, we analysed the survival and development of S. frugiperda fed on pea leaves in the laboratory and constructed age-stage and two-sex life tables. Results showed that FAW successfully completed its life cycle when fed on pea and produced fertile offspring. The pre-adult duration was significantly higher on pea than maize. The net reproductive rate, intrinsic and finite rate of population increase on pea (135.06 offspring per individual, 0.12 offspring per individual per day and 1.13 times per day) were all significantly different from those on maize (417.64 offspring per individual, 0.19 offspring per individual per day and 1.21 times per day). The probability of survival of S. frugiperda at each stage was lower when fed on pea leaves than that of maize-fed larvae. Due to the overlapping growth periods of the maize and pea, S. frugiperda can easily proliferate throughout the year by shifting between adjacent crops. Thus, this study revealed the adaptability of S. frugiperda for pea and provides the foundation for further assessment of FAW risk to other inter-crops.

Many insect pests, including the brown planthopper (BPH), undergo windborne migration that is challenging to observe and track. It remains controversial about their migration patterns and largely unknown regarding the underlying genetic basis. By analyzing 360 whole genomes from around the globe, we clarify the genetic sources of worldwide BPHs and illuminate a landscape of BPH migration showing that East Asian populations perform closed-circuit journeys between Indochina and the Far East, while populations of Malay Archipelago and South Asia undergo one-way migration to Indochina. We further find round-trip migration accelerates population differentiation, with highly diverged regions enriching in a gene desert chromosome that is simultaneously the speciation hotspot between BPH and related species. This study not only shows the power of applying genomic approaches to demystify the migration in windborne migrants but also enhances our understanding of how seasonal movements affect speciation and evolution in insects.