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The fall armyworm, Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae), is a highly destructive insect pest that negatively affects various agricultural crops. For environmentally safe means of its control, we evaluated the effectiveness of four plant essential oils: mint, Mentha piperita, citrus lime, Citrus sinensis, lemongrass, Cymbopogon citratus, and eucalyptus, Eucalyptus camaldulensis, against S. frugiperda larvae in terms of mortality rate and their antifeedant activity. A total of 78, 73, 52 and 26 compounds were detected in EOs of C. citratus, E. camaldulensis, C. sinensis and M. piperita, respectively. A high variation in the major compounds and percentages of these compounds was: C. citratus (3,8-nonadien-2-one, 4,8 dimethyl, 23.66%), E. camaldulensis (eucalyptol, 42.21%), C. sinensis (apiol, 5.59%) and M. piperita (cubenol, 8.43%). Three different concentrations (1.0%, 3.0% and 5.0%) of each essential oil were tested against 3rd larval instar. All essential oils caused mortality, but M. piperita and E. camaldulensis were the most effective at higher concentration. At concentration of 5.0%, M. piperita caused 93.3% larval mortality after 72 h of application. Similarly, E. camaldulensis oil caused 83.3% larval mortality after 72 h with 5.0% concentration. Furthermore, at 5.0% concentration, M. piperita oil had an antifeedant activity of 80.4%, and E. camaldulensis oil showed 71.3%. The findings indicate the potential use of M. piperita and E. camaldulensis oils to control S. frugiperda. The utilization of these oils offers an environment friendly approach, which can effectively address the issue of insecticide resistance in S. frugiperda. [ABSTRACT FROM AUTHOR]

Citrus is one of the major fruit crops worldwide due to its contribution to food security. Citrus orchards serve as a habitat for arthropods plethora including beneficial and harmful arthropods. Extensive field surveys were conducted to assess the diversity and abundance of arthropods from citrus plantations at six tehsils (Kotmomin, Bhalwal, Silanwali, Shahpur, Sahiwal, and Sargodha) of district Sargodha. Different traps were installed for the collection of arthropods i.e., pitfall, yellow pan, yellow sticky cards, and soil sampling. The traps were visited after every two weeks for the collection of arthropods for two consecutive years. The relative abundance of Pseudococcidae was higher (0.35%) followed by Scarabaeidae (0.14%), Carabidae (0.07%), and Chrysomelidae (0.07%) in pitfall traps. In the case of the yellow pan, the abundance of Nitidulidae (0.27%), Psyllidae (0.17%), Tetranychidae (0.23%), and Aphididae (0.09%) was higher compared to other families. Similarly, Psyllidae (0.60%), Aleyrodidae (0.25%), and Aphididae (0.24%) families of arthropods were abundant when yellow sticky cards were used. While from the soil samples, more individuals from Isotomidae (0.41%), Oribatulidae (0.39%), and Hypogastruridae (0.27%) families were collected. Based on the extensive surveys, a total of 50,966.5 citrus-associated arthropods were collected during 2018-2019, among which 20,873 were Coleopterans belonging to 7 different families. Our findings provide the baseline information for the development of Integrated Pest Management (IPM) measures against insect pests in citrus orchards to increase our citrus production. [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]

The armyworm, Spodoptera litura Fab. (Lepidoptera: Noctuidae) is an economically important insect pest of vegetables, ornamentals and other agricultural crops. Synthetic insecticides have remained primary means for the management of S. litura than any other management tool. We tested the effectiveness of some insecticides against different larval instars of S. litura in laboratory as well as in field on the prevailing instars in two fodder crops lucern/alfalfa, Medicago sativa L. and jantar/sesbania, Sesbania sesban L. In the laboratory, emamectin benzoate provided the most control 69-91% followed by lufenuron 70-85% of all larval instars after 48 hours of application. In the lucern field, emamectin benzoate reduced the larval population of S. litura up to 79.32% and with the application of lufenuron 73.55% reduction occurred. Similarly, in jantar crop, lufenuron and emamectin benzoate proved to be more toxic against S. litura population. The abundance of ladybird beetle, Coccinella septempunctata L. (Coleoptera; Coccinellidae), honeybee, Apis mellifera L. (Hymenoptera; Apidae) and green lacewing, Chrysoperla carnea Stephen (Neuroptera; Chrysopidae) were found higher in emamectin and lufenuron treated plots compared to methoxyfenozide and chlorpyrifos. These results indicate that new chemistry insecticides; emamectin benzoate and lufenuron have a potential for the management of S. litura and are relatively safer for beneficial insects as compared to conventional insecticides, methoxyfenozide, and chlorpyrifos. [ABSTRACT FROM AUTHOR]

Background: Temperature alters host suitability for the development of parasitoids through direct (thermal effect) and indirect (parental effect) pathways. The effects of three temperature regimes on the development and survival of two parasitoid species, Citrostichusphyllocnistoides (Narayanan) and Cirrospilusingenuus Gahan (Eulophidae: Hymenoptera) of the citrus leafminer, Phyllocnistiscitrella Stainton (Lepidoptera: Gracillariidae) was evaluated. The experiment was conducted at 20, 25, and 30°C temperatures with 65 ± 2% relative humidity (R.H.) and 16h: 8h (L: D) photoperiod. Results: In C.phyllocnistoides, the pre-ovipositional period was longer at 20°C, while non- significant difference was observed in the pre-ovipositional period of C.ingenuus under the effect of different temperatures (P > 0.05). The ovipositional period of C.phyllocnistoides and C.ingenuus was higher at 20°C and gradually decreased by increasing the temperature. Non- significant (P > 0.05) difference was found in post-ovipositional period of both parasitoid species. Both species exhibited the maximum fecundity at 25°C, while, the minimum fecundity was recorded at 30°C. However, the adult longevity of both parasitoid species was highest at 20°C and gradually decreased by increasing the temperature. In both parasitoids, the parasitism rate was highest at 25°C. Conclusion: This study highlighted the importance of thermal effects on some parasitoid species of insect pests to predict the future of trophic dynamics in global warming situations. [ABSTRACT FROM AUTHOR]