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Background Thrips tabaci Lindeman (Thysanoptera: Thripidae) is the key pest of onions that causes economic yield losses in commercial onion production in Pakistan. In this study, potential of the entomopathogenic fungi (EPF), Beauveria bassiana and Metarhizium anisopliae, as a bio agent was evaluated to manage buildup of thrips population on onion crop. Results Efficacy tests for EPF were conducted against T. tabaci infesting 3 different onion varieties (Phulkara, Swat 1, and Virio 7). Commercial formulations of B. bassiana strain GHA and M. anisopilae strain ESC-1, were evaluated at 4 different concentrations (108, 109, 1010, and 1011 conidia/ml) under field conditions for 2 years. The efficacy was assessed 3, 5, 7, and 10 days after spray application of the whole onion plant. Efficacy expressed as T. tabaci (nymphs and adults) percent population reduction in comparison to controls. Maximum corrected percent population reduction was observed in onion plants treated with B. bassiana 1011 conidia/ml, i.e., 86.62, 84.59, and 86% in Phulkara, Swat 1, and Virio 7 onion varieties respectively, after 10 days of spray application. While onion plants treated with M. anisopliae 108 conidia/ml showed minimum corrected percent population reduction, i.e., 69.42, 68.45, and 69.11% in Phulkara, Swat 1, and Virio 7 onion varieties respectively, after 10 days of spray. Conclusions Beauveria bassiana could significantly reduce thrips population and could provide a better long-term management of T. tabaci on onion. B. bassiana had a high toxic effect against offspring production of the T. tabaci under field conditions than M. anisopliae.

Eleven inbred silkworm lines (M-101, M-103, M-104, M-107, Pak-1, Pak-3, Pak-2, Pak-4, PFI-1, PFI-2, and S-1) were evaluated for various parameters of cocoon production under different temperature and relative humidity conditions (25±1, 30±1, and 35±1• C in combination with 55, 65, and 75% RH for three hrs during 4th and 5th instar. The experiment was laid out in factorial design with three replications. Significant variations in the performance of silkworm lines were noticed due to influence of temperature and RH treatment on 4th and 5th instar larvae. The silkworm lines performed significantly better when the larvae were reared at 25 ± 1• C with 70-80% RH while almost all the silkworm lines showed poor performance at higher temperature exposures for 3 hrs. Exposures to lower humidity (55%) during larval rearing in 4th and 5th instar at different temperatures (25 ± 1, 30 ± 1, and 35±1• C) resulted in lowering the cocoon production. The cumulative evaluation index values for different traits showed that Pak-4 (61.42) was the best line followed by M-101 (59.15), Pak-2 (56.37), Pak-3 (52.83) PFI-I (52.62), and M-107(50.03). The study clearly underlines the importance of optimization of environmental conditions during larval rearing in relation to commercial cocoon production. The investigations strongly recommend that temperature and relative humidity in the range of 25-26• C and 70-80%, respectively, are mandatory for excellent results of cocoon production and Pak-4, M-101, Pak-2, Pak-3, PFI-I, and M-107 were suitable for commercial rearing.

to check the efficacy of commercial biopesticides under controlled environmental conditions. Bio pesticides are important alternates for chemical control of economically damaging insect pests like leaf worm, Spodoptera litura Fabricius. In this study, two commercial products including Dipel with Bt sub speciess kurstaki and Turex with Bt sub speciess kurstaki and aizawai were tested against three early larval instars of S. litura under laboratory conditions using leaf dip method. Mortality was recorded after three and seven days of exposure. The results indicated that larval mortality increased with time and Turex (Bt sub speciess kurstaki and aizawai) after 3 days of exposure caused significantly higher mortality i.e 46.43, 43.45 and 38.69 % as compared to Dipel (Bt sub speciess kurstaki) that caused 19.05, 6.55 and 4.76 % mortality for 1 st , 2 nd and 3 rd instar, respectively. The data for 7 th day also showed significantly higher mortality as 64.29, 60.71 and 45.24 % by Turex (Bt sub speciess kurstaki and aizawai) in comparison with 55.95, 57.74 and 42.86 % mortality by Dipel (Bt sub species kurstaki) for 1 st , 2 nd and 3 rd instar, respectively. Susceptibility to both bio pesticides increased with increase in their concentration and decreased with increase in larval instar. Similarly LC 50 values suggested Turex (Bt sub species kurstaki and aizawai) to be more toxic with less LC 50 values as compared to Dipel (Bt sub species kurstaki). These results indicated that these bio pesticides if used at early insect stage can help to control this pest.

Background Bactrocera cucurbitae (Coquillett) (Diptera: Tephritidae) is the most destructive pest of bitter gourd. Conventionally, it is controlled by chemical insecticides despite their hazardous impacts. Entomopathogenic fungi are considered as eco-friendly and safer alternative of chemical. This study aimed to evaluate the efficacy of Beauveria bassiana and Metarhizium anisopliae against B. cucurbitae on bitter gourd. Results The study revealed that B. bassiana and M. anisopliae were efficient against B. cucurbitae in controlled as well as field conditions. Both mode of application (i.e., contact and oral) were found to be effective; however, high efficacies of them were observed through contact application (73.43 and 59.72%), respectively. Pathogenicity of both fungi increased with increase in concentration and time intervals. Under field conditions, significantly low fruit infestations and significantly a high population reduction of B. cucurbitae were observed at 30 DAT when both fungi were applied with 108 CFU/ml concentrations. Conclusions Beauveria bassiana and M. anisopliae had the potential to be used against B. cucurbitae; however, the former showed high efficiency comparatively.