Insect species inventories along with pest prevalence, foraging behavior of pollinators and their effect on fruit set of mango were studied in a mango‐based agroforestry area in Bangladesh during January to June 2013. Of 1751 collected insects, 11 species in five orders and nine families were pests, 13 species in six orders and eight families were predators and eight species belonging to three orders and seven families were found as pollinators. The pests exerted significantly higher abundance but lower diversity than pollinator, predator and other insects. The pollinator richness was found to be lowest but showed higher as well as similar diversity to other category insects. Three pest species prevailed throughout the season and hoppers showed significant abundance. Among the predators, ants were most abundant. Sulphur butterfly and syrphid fly revealed statistically identical and higher abundance than other pollinators. During the flowering season, pests were dominant and the abundance of insects was observed to peak at 11.00 h. The pollinators differed in their landing duration on flowers and their activity led to higher levels of fruit set. This study provides baseline information on insect abundance in an agroforestry system, which stresses the importance of conservation of beneficial insects.

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The abundance, infestation, and severity of the mite Polyphagotarsonemus latus were studied on the chili (Capsicum frutescens L., Solanaceae) varieties BARI Morich 1, BARI Morich 2, BARI Morich 3, BINA Morich 1, and Bogura Morich from November 2017 to June 2018. The abundance of mites was found from 05 February to 28 May, and the peak abundance on the chili varieties occurred on 09 April. Mite population showed the highest and the lowest occurrences on BINA Morich 1 and BARI Morich 2, respectively. The abundance of P. latus on the chili varieties showed significant positive correlation with temperature, and the relationship with relative humidity and rainfall was negative. Mite population was negatively correlated with leaf trichomes of all the chili varieties, and depicted significant negative correlation with the leaf area of BARI Morich 1, BARI Morich 3 and BINA Morich 1. The number of flower of the chili varieties BARI Morich 3 and BINA Morich 1, and number of fruit of the varieties BARI Morich 1, BARI Morich 3, BINA Morich 1 and Bogura Morich showed significant negative correlation with mite population. The chili varieties demonstrated significant differences within their leaf curl indices (LCI), and infestation levels of flower and fruit. The BARI Morich 2 revealed the lowest level of mite infestation on flowers and fruits. The varieties BARI Morich 1, BARI Morich 2, and Bogura Morich contained <50% LCI, which were categorized as moderately resistant, and the rest varieties were categorized as susceptible due to >50% LCI.

The population abundance, infestation, and harmful effects of the aphid Aphis craccivora Koch (Hemiptera: Aphididae) were studied on four bean plant species, namely the country bean (Lablab purpureus var. BARI Seem 1), the yard‐long bean (Vigna sesquipedalis var. BARI Borboti 1), the hyacinth bean (Dolichos lablab var. BARI Seem 6), and the bush bean (Phaseolus vulgaris var. BARI Jar Seem 3). Aphid abundance and infestation on the leaves, inflorescences, flowers, and pods differed significantly among the bean plant species, with P. vulgaris and V. sesquipedalis having the lowest and highest results, respectively. Aphid severity grade and the number of trichomes of the bean plant species were negatively correlated. The duration of the growth stages among the bean plant species were significantly different, with V. sesquipedalis having the shortest durations. Aphid abundance and infestation significantly affected the physical and phytochemical characteristics of the bean plant species. The highest reduction of number of leaves, flower inflorescences, and pod inflorescences per plant, and moisture and chlorophyll content in the leaves was found in L. purpureus. The results for V. sesquipedalis revealed the highest reduction in plant height, seed weight, and pH, while those of D. lablab showed the highest reduction in leaf area.

The study was conducted with the aim of furthering our understanding of seasonality in the population dynamics and infestation rates of the fruit fly Bactrocera spp. in sweet gourd (Cucurbita moschata) during winter and summer in 2017. We also investigated the effects of using methyl eugenol traps on fly abundance and infestation. Two fruit fly species, namely, B. cucurbitae and B. dorsalis, were present in the sweet gourd field, and we observed fluctuations in their abundance. Compared to B. dorsalis, B. cucurbitae was significantly more abundant in both winter and summer. Infestation level was found to be the highest in fields lacking methyl eugenol traps in both seasons. Fruit fly larval population per infested fruit was higher in summer than in winter. Fly abundance was significantly and positively correlated with mean temperature and rainfall but significantly and negatively correlated with light intensity. Relative humidity was insignificantly but positively correlated with fly abundance. The temperature, light intensity, relative humidity, and rainfall individually explained 48.9, 24.1, 0.8, and 1.6% of variation in fruit fly abundance, respectively. The combined effect of the weather parameters on fruit fly abundance was 75.4% and was significant predictor of fruit fly abundance.