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The appearance and rapid spread of the fall armyworm (Spodoptera frugiperda) (FAW) represents a serious threat to maize cultivation in India and elsewhere in South Asia. Chemical control illustrates one of the major means of reducing the infestation of FAW in maize-growing zones. However, existing information regarding the field-efficacy and non-target toxicity of different insecticides against this pest is not adequate and is also unable to capture the momentum change in the scenario of residual toxicity and insecticide resistance for redacting sustainable management. The present study was framed to establish the most suitable insecticidal schedule against FAW for maize producers. In the period from winter 2019–2020 to spring–summer 2020, seven treatment schedules against FAW were evaluated, and the efficacy was calculated according to the per cent maize plant damage (PD) by larvae, while safety was enumerated based on larval parasitization by Campoletis chlorideae and the abundance of coccinellid predators. In both seasons, the highest cumulative efficacy (9.88 and 10.19% PD) was confirmed for T3 (constituted with Barazide®, Delegate®, and Ampligo®) with a significantly higher yield (52.39 and 52.66 q ha−1), whereas T7 (Proclaim Fit®, Ampligo®, and Delegate®) and T6 (Fimecta®, Ampligo®, and Spintor®) exhibited a high cumulative efficacy (11.06 to 12.23% PD). T3 was found to be safe to coccinellid predators and the per cent larval parasitism by C. chlorideae was significantly higher in this module (2.57 and 2.75%) compared to T4 and T5 (1.00 to 1.67%). The residues of Barazide®, Delegate®, and Ampligo® were below detectable levels in maize plant, grain and soil samples. Therefore, the module could be recommended against FAW in the near future. [ABSTRACT FROM AUTHOR]

Whitefly (Bemisia tabaci Gennadius) is a devastating pest of vegetables, cotton, and many other agricultural and horticultural crops worldwide. Since control of B. tabaci on vegetable crops solely depends on the use of chemical insecticides in India; monitoring the insecticide resistance of B. tabaci populations would be very much essential for achieving successful control and for managing the resistance development. Hence, the aim of the present study was to examine the resistance in different field strains of B. tabaci to traditional organophosphates and new chemical insecticides in India. The resistance ratios were recorded in the range of 30.67-131.48 fold for acephate, 29.17-83.67 fold for triazophos, 0.38-2.51 fold for indoxacarb, 4.55-34.52 fold for dinotefuran, 6.26-27.56 fold for tolfenpyrad, 7.87-31.89 fold for spiromesifen, 1.61-30.08 fold for pyriproxyfen, and 3.09-45.92 fold for flonicamid in comparison to that of the susceptible strain in the laboratory. Resistance levels of B. tabaci populations against the tested insecticides were significantly variable among localities. The present data will be helpful for the selection of proper insecticides on vegetable crops in the field for successful management of B. tabaci in near future. [ABSTRACT FROM AUTHOR]

The cotton whitefly, Bemisia tabaci (Gennadius) is a devastating polyphagous insect pest worldwide and has been shown to be resistant to insecticides in most chemical classes. The newly commercialized pyropene insecticide afidopyropen provided a new tool to control B. tabaci because of high selectivity and its novel mode of action. This study aimed to evaluate the susceptibility of B. tabaci Asia I from ten provinces of India to afidopyropen and other commonly used insecticides. Most field-collected populations were susceptible to afidopyropen, with LC 50 values varying from 4.37 to 16.62 mg L−1. However, four field populations (W-MH, K-UP, M-WB and L-PN) exhibited moderate levels of resistance (28.53, 19.09, 35.27 and 30.81-fold, respectively), but no cross-resistance to cyantraniliprole and pymetrozine. Diethyl maleate (DEM) significantly restored the susceptibility of W-MH, M-WB and L-PN strains of B. tabaci to afidopyropen, whereas piperonyl butoxide (PBO) significantly inhibited afidopyropen resistance in K-UP, M-WB and L-PN populations. The activities of glutathione S -transferase (GST) and P450 monooxygenase increased in the afidopyropen-resistant field strains, while esterase activity did not change significantly. The present study showed a regional variation in afidopyropen toxicities among B. tabaci Asia I populations from different agro-climatic zones of India, which suggests a potential risk of afidopyropen resistance development. Metabolic detoxification mediated by GST and P450 monooxygenase was associated with afidopyropen resistance in B. tabaci Asia I. [Display omitted] • First report of afidopyropen resistance in Bemisia tabaci Asia I. • Four field-strains exhibited moderate level of resistance. • No cross-resistance of afidopyropen with cyantraniliprole or pymetrozine. • Elevated GST and P450 activities in afidopyropen-resistant populations. [ABSTRACT FROM AUTHOR]

Leucinodes orbonalis Guenee (Pyraustidae: Lepidoptera) is a fruit and shoot borer which is the key pest of eggplant (also known as brinjal and aubergine). L. orbonalis causes broad-based problems in eggplant cultivation. An effort was made to control the borer during the Indian rainy season, as this is the time when the problem is at its worst. The impact of treatments on natural enemies as well as pollinators was also assessed. Integration of phytosanitation, mechanical control and prophylactic application of neem seed kernel extract (NSKE) exerted a satisfactory impact on the incidence and damage of L. orbonalis. After two need-based applications of new generation pesticide molecules like flubendiamide or rynaxypyr or emamectin benzoate, fairly good, healthy yields were produced. A ready-mix formulation (triazophos 40% + cypermethrin 4%), and carbofuran also offered good protection against the borer but both were found highly toxic and unsafe for predators i.e. predatory coccinellids and spiders and pollinating bees. Flubendiamide and rynaxypyr appeared comparatively more unsafe for bees than emamectin benzoate, while both allowed a substantial proportion of coccinellids and spiders to survive. Naturolyte, with the active ingredient emamectin benzoate, was found safe for predators and bees and on par with the untreated check. [ABSTRACT FROM AUTHOR]