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An in vitro experiment was conducted at the Organic Farming Research Centre (OFRC), KSNUAHS, Shivamogga, to investigate the toxicity of six different insecticides, viz., spinosad 45% SC, fenpropathrin 30% EC, cypermethrin 25% EC, chlorantraniliprole 18.5% SC, malathion 50% EC and flubendiamide 39.35% SC, against third-instar larvae of Brinjal shoot and fruit borer, Leucinodesorbonalis (Guenee), via the fruit dip bioassay method. The results indicated that chlorantraniliprole was 1.59, 3.72, 7.19, 10.16 and 11.98 times more toxic than Spinosad, flubendiamide, cypermethrin, malathion and fenpropathrin, respectively. Chlorantraniliprole 18.5% SC proved to be highly persistent among the tested insecticides where it effectively controlled L. orbonalis larvae, reducing their population for up to 11 days post-treatment, with a recorded PT50 value of 7 days. Next best persistent insecticides were spinosad and flubendiamide with PT50 values of 6 days and 4.5 days, respectively. Compared to conventional insecticides, diamide and spinosyn insecticides were more toxic to L. orbonalis. Hence, compared with other insecticides, chlorantraniliprole 18.5% SC with novel mode of action was highly toxic to larvae of L. orbonalis, with the lowest LC50 values and high persistence. [ABSTRACT FROM AUTHOR]

The invasion of maize (Zea mays L.) in 2018 by fall armyworm, Spodoptera frugiperda (J.E. Smith), threatened food security of India. In the early stage of crop growth, spray is difficult to apply because of the small size of the plant, waste of insecticide, and harm to non-target organisms. Seed treatment alone and combined with foliar spray were evaluated to manage fall armyworm in the field in June and September 2019. The experiment was a randomized block design with eight treatments. The maize seed treatments viz., chlorantraniliprole 250 g a.i./100 kg seeds alone, cyantraniliprole + thiamethoxam 238 g a.i./100 kg seeds, and cyantraniliprole + thiamethoxam 317 g a.i./100 kg seeds managed fall armyworm larvae and reduced plant damage 1 week after emergence of the crop compared with the check. A sequence of two foliar sprays resulted in the highest yield, followed by seed treatment plus a foliar spray (cyantraniliprole 19.8 + thiamethoxam 19.8 FS 8 ml/kg of seeds + emamectin benzoate 5 SG 0.4 g/liter), and seed treatments (chlorantraniliprole, cyantraniliprole+thiamethoxam). Most net returns were from cyantraniliprole 19.8 + thiamethoxam 19.8 FS 317 g a.i./100 kg of seeds and foliar application of emamectin benzoate 5 SG 12.5 g a.i./ha (US $581); the nontreated check had only US $123/ha net return. La invasión al maíz (Zea mays L.) en 2018 por el gusano cogollero Spodoptera frugiperda (J.E. Smith), amenazó la seguridad alimentaria de India. La aspersión de insecticidas es difícil de realizar en la etapa inicial de crecimiento del cultivo debido al tamaño pequeño de la planta, el desperdicio de insecticida y el daño a organismos no-objetivo. Se evaluó el tratamiento de semillas por sí solo y en combinación con aspersión foliar en junio y septiembre de 2019 para controlar el gusano cogollero en el campo. El experimento fue un diseño de bloques al azar con ocho tratamientos. Los tratamientos de semilla del maíz incluyendo clorantraniliprol 250 g i.a./100 kg de semillas solas, ciantraniliprol + tiametoxam 238 g i.a./100 kg de semillas y ciantraniliprol + tiametoxam 317 g i.a./100 kg de semillas redujeron las larvas del gusano cogollero y el daño a las plantas 1 semana después de la emergencia del cultivo en comparación con el control sin tratamiento. Una secuencia de dos aspersiones foliares dio como resultado el mayor rendimiento, seguido de un tratamiento de semillas más una aspersión foliar con (ciantraniliprol 19.8 + tiametoxam19.8 FS 8 ml/Kg de semillas – benzoato de emamectina 5 SG 0.4 g/litro) y tratamientosde semilla con (clorantraniliprol, ciantraniliprol + tiametoxam). La mayor parte de los rendimientos netos se observaron con ciantraniliprol 19,8 + tiametoxam 19,8 FS 317 gi.a./100 kg de semillas y aplicación foliar de benzoato de emamectina 5 SG 12,5 gi.a./ha (US $581); con el control sin tratamiento se obtuvieron solamente US $123/ha de rendimiento neto. [ABSTRACT FROM AUTHOR]

Fall armyworm Spodoptera frugiperda (J E Smith) has become a devastating pest in maize. Field experiments were carried out to assess the efficacy of various IPM modules against this pest. Amongst these, biointensive module recorded highest number of coccinellids (1.27/ plant) and ants (0.42/ plant), while chemical control module led to highest larval reduction over control (86.04%) and being superior with significantly higher grain yield (53.45 q/ ha). This also gave a 1.86 B:C ratio followed by the IPM module (48.06 q/ ha) with 1.85 B:C ratio. [ABSTRACT FROM AUTHOR]

The present study aimed to ascertain the sublethal effects of azadirachtin 1 EC, anosom 1 EC, derisom 2 EC and NSKE 5% on biological parameters and nutritional indices of Spodoptera frugiperda. The longest larval and pupal lengths were observed in all the treatments involving botanicals, which also significantly decreased adult longevity, fecundity and egg hatchability. Regarding nutritional indices, larvae treated with anosom recorded the least approximate digestibility index, efficiency of conversion of digested food and efficiency of conversion of ingested food of 64.7%, 13.2% and 8.4% respectively. Additionally, botanicals increased the percentage of defective and malformed adults. Thus, our findings suggest that these botanicals restrain the pests from causing damage and impede their further generations. [ABSTRACT FROM AUTHOR]

Euhamitermes Holmgren is a soldier rare, soil feeding termite of the Oriental region. Two species of this genus viz., Euhamitermes lighti (Snyder) and Euhamitermes chhotanii Maiti are hereby first reported from southern Indian states of Karnataka and Kerala, respectively. Record of E. chhotanii in Kerala makes an addition of the genus and thus to the termite fauna of Kerala. These two species are redescribed and illustrated based on soldier and workers. [ABSTRACT FROM AUTHOR]

Dewinged termite imagoes are considered to be delicious human food around the world. The nutrient composition may vary with respect to the species. In the present study, imagoes of three termite species, viz. Odontotermes obesus, Coptotermes heimi and Microtermes obesi were used to compare their protein composition. Additionally, the commonest species, O. obesus was used for proximate and mineral composition analysis. The nutritional analysis of termites indicated a higher percentage of protein in C. heimi, followed by O. obesus. The proximate analysis of O. obesus imagoes revealed a higher proportion of crude fat followed by crude protein. Macrominerals were recorded in a higher proportion with potassium as one of the major minerals followed by sodium, while in microelements iron and zinc were represented in greater quantities. [ABSTRACT FROM AUTHOR]

Invasion of fall armyworm (FAW), Spodoptera frugiperda (Lepidoptera: Noctuidae) has been implicated in reducing the incidence of native stem borers in India. The present study aimed to verify the reasons for the displacement of native stem borers using S. frugiperda and pink stem borer, Sesamia inferens (Walker) (Lepidoptera: Noctuidae). Field incidence of FAW and S. inferens was recorded during the 2020 and 2021 wet seasons, indicating negligible field incidence of S. inferens compared to FAW. In controlled greenhouse experiments, the competition was measured by releasing larvae at different densities into the maize whorl and also by varying their release at two-day intervals among the two species tested. In competition assays, the frequency of cannibalism increased with increasing density. The study documents that cannibalistic nature and early habitat occupancy in the whorls by FAW are the key factors involved in reducing the incidence of native stem borer, S. inferens. [ABSTRACT FROM AUTHOR]