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The two-spotted spider mite (TSSM), Tetranychus urticae Koch is a polyphagous widespread herbivore pest and one of the most economically important species which feeds more than 1,100 plant species. The functional response at five different constant temperatures (15, 20, 25, 30 and 35 °C), prey switching, and mutual interference behaviors of the predatory coccinellid, Stethorus gilvifrons Mulsant on TSSM nymphs were assessed in laboratory conditions (25 ± 1 °C, 60 ± 5% RH and L:D 16:8 h) to evaluate its potential for biological control of TSSM. The predator showed a type II functional response at all tested temperatures. The shortest handling time (Th) and highest searching efficiency (α) were obtained at 30 °C and 20 °C, respectively. The highest and lowest values of the maximum attack rate (T/Th) of the predator were obtained at temperatures of 30 °C and 15 °C, respectively. The switching behavior was not observed in S. gilvifrons between different density proportions of TSSM nymph and adult. The highest value of total predation and lowest value of per capita predation rate belonged to the predator density of 16. The results revealed a strong predation capacity of S. gilvifrons on TSSM, especially in higher temperatures which makes it an efficient biocontrol agent in integrated TSSM management programs. [ABSTRACT FROM AUTHOR]

Nineteen insect species from four major insect orders viz., Hemiptera, Lepidoptera, Coleoptera, and Orthoptera, were found belong to sixteen families damaging common bean, which is also known as French bean cultivation in subtropical climates. Among the insect pests, sucking insects occupies maximum incidence; aphid, Aphis craccivora Koch incidence was peak in both seasons 2018 (77.4 aphids/plant) and 2019 (77.6 aphids/plant) during 8th SMW followed by Leafhoppers, Empoasca kerri Pruthi (6.4 Nos/plant). The impact of weather factors on the insect populations showed that minimum temperature negatively correlated with aphids (r =—0.189), leafhopper (r = -0.315) populations and positively correlated with whitefly, Bemisia tabaci Gennadius (r = 0.118) and thrips, Thrips palmi Karny population (r = 0.052). Relative humidity and rainfall were negatively correlated with French bean sucking pests. In defoliators, serpentine leaf miner, Liriomyza trifolii Burgess larvae incidence was high in both seasons (18.4 larva/plant) and (20.6 larva/plant) followed by hairy caterpillar, Euproctis fraterna Moore (1.4 larva/plant) and leaf folder, Nacoleia spp (1.15 larvae/plant). Among the pod borers, spotted pod borer, Maruca vitrata incidence was higher than others and influenced by both maximum (r = 0. 791) and minimum temperature (r = 0.714). Relative humidity and wind speed parameters were negatively correlated with pod borers viz., M. vitrata Fabricius and Helicoverpa armigera Hubner respectively. The model ARIMAX (3, 0, 0) of aphids showed that the incidence of the pest depended on the weather parameters such as minimum temperature, relative humidity, and rainfall significantly. The ARIMAX (2, 0, 0) model of M. vitrata showed that the weather parameters such as maximum temperature, minimum temperature and relative humidity played a significant role in the incidence of the M. vitrata. [ABSTRACT FROM AUTHOR]

Worldwide application of synthetic insecticides as a main way of controlling aphids on various crops has resulted in diverse problems such as failures in pest control, negative public health and environmental impacts, and a build-up of resistance against insecticides by insect pests. Entomopathogenic fungi can be used as an alternative to insecticides since they offer the benefit of being environmentally friendly, without the risk of insect pests developing resistance. This study assessed 19 different indigenous fungi in the laboratory for their ability to control Aphis fabae Scopoli at various conidial concentrations (104, 105, 106 and 107 spores/ml) using the detached leaf method. A. fabae adults were reared on potted cowpea in cages. Both the 19 fungus types and their respective conidial concentrations used to treat A. fabae differed significantly (P < 0.001) in their ability to kill the pest. The A. fabae mortality rate increased in line with the increase in the conidial concentration of the fungus type, and Aspergillus flavus Link S18 and S19 performed better than the other fungus types evaluated. Aspergillus flavus S18 and S19 are recommended for further tests in the greenhouse to validate the laboratory results. The fact that the Aspergillus strains isolated and tested were all aflatoxin-producing strains calls for caution regarding their potential impacts on human and animal health. Further studies are recommended to conduct similar experiments using non-aflatoxin-producing strains of A. flavus, in order to determine whether they have similar effects on A. fabae. [ABSTRACT FROM AUTHOR]