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An assay was designed to evaluate the efficacy of each entomopathogenic fungus, Beauveria bassiana, and diatomaceous (DE) and their combinations at concentrations of 1 × 106and 1 × 108conidia kg−1of wheat and 200 and 400 ppm, respectively, on the red flour beetle, Tribolium castaneum(Herbst) (Tenebrionidae: Coleoptera), infesting wheat. Percent mortality of T. castaneumwas recorded after 7, 14, and 21 days. Percent mycosis on dead cadavers was assessed after 21 days. Alive adults were removed from plastic jars after 21 days and kept for the next 60 days to assess the progeny production. The results indicated that the highest concentrations of B. bassianaand DE in their combinations were more effective for the virulence and progeny suppression of T. castaneum. Maximum mean percent mortality (88.13%) was recorded by B. bassiana(1 × 108conidia kg−1of wheat) and DE (400 ppm) in their combination after a 21-day exposure interval, while a minimum percent mean mortality (10.00%) was recorded by B. bassiana(1 × 106conidia kg−1of wheat) alone. The maximum percent mycosis (78.89%) on dead cadavers was recorded at a low concentration rate (1 × 106conidia/kg) of B. bassiana. Mean progeny adult emergence was the highest (62.67 adults) at the low concentration of B. bassianaalone. Present studies showed that B. bassianaand DE are more effective in combination against T. castaneumon wheat as both substances are advantageous.

The rice leaf roller or leaf folder, Cnaphalocrocis medinalis(Guenee) (Lepidoptera: Pyralidae), is a serious pest of rice crop in Pakistan. The present study was carried out to evaluate the virulence of the entomopathogenic fungi (EPF) Beauveria bassiana, Verticillium lecanii, and Metarhizium anisopliaeagainst the third instar of C. medinalislarvae. Larvae were exposed to fungi under controlled conditions at the available commercial concentration (1 × 108conidia ml−1). The results showed 73.33, 57.78, and 74.44% mortality rates in the in vitro assay and 56.67, 41.11 and 52.78% in the greenhouse assay of B. bassiana, V. lecanii, and M. anisopliae, respectively. The maximum mycosis from cadavers of C. medinaliswas observed at B. bassianatreatment in the in vitro assay (70%) and in the greenhouse assay (53.78%). The maximum sporulation from C. medinaliscadavers was observed at B. bassianatreatment in the in vitro assay (144.67 conidia ml−1) and in greenhouse assay (96.67 conidia ml−1). These results favor the alternative use of EPF in organic rice production for management of C. medinalis.

Background: The peach fruit fly, Bactrocera zonata(Saunders) (Diptera: Tephritidae), is a serious polyphagous pest of fruits and vegetables. Chemical management of B. zonatain fruits results in toxic residues that have adverse health effects on consumers resulting in increased demand for eco-friendly approaches. Laboratory bioassay was conducted to determine the pathogenicity of fungal and bacterial biopesticides against B. zonata. Results: The pathogenicity of all tested bioinsecticides revealed that the maximum concentration (1 × 108CFU ml−1) of Metarhizium anisopliae, Beauveria bassiana, Lecanicillium lecaniiand Bacillus thuringiensiscaused 95.8–100%, 95.9–97.9%, 32.7–39.6%, and 20.0–22.4% mortality in B. zonata, respectively at 7 d post-application interval (PAI) as compared to mortality demonstrated by the same concentration at 5 d PAI. All tested microbial insecticides induced statistically similar mortality in both male and female B. zonataat each concentration for the same PAI. Correlation coefficient (r) values reveal that concentrations of each microbial insecticide had a high positive correlation with mortalities of male and female B. zonata. Regression parameters reveal that concentrations of tested microbial insecticides had significant linear relationship with and explained significant variability in B. zonatamortality (P< 0.05). Results also revealed that M. anisopliaewas proved more pathogenic to males and females of B. zonatademonstrating the least LC50values (5.48 × 103, and 6.17 × 103CFU ml−1, respectively) 7 d post-application intervals, followed by B. bassianawhich explained LC50value of 1.14 × 104CFU and 1.15 × 105CFU ml−1for B. zonatamales and females, respectively, at the same period of application, but less than that of L. lecanii(2.77 × 109and 1.43 × 109CFU ml−1) and then B. thuringiensis(3.40 × 1010and 1.39 × 1010CFU ml−1) for the males and females, respectively, at 7 d PAIs. Conclusion: Metarhizium anisopliaeincorporated adult diet was proved more effective against B. zonata,followed by B. bassiana, L. lecanii, and B. thuringiensis. Hence, M. anisopliaecan be recommended for incorporating in bait-traps to develop attract-and-kill technology for B. zonata.

Compatibility of entomopathogenic fungi (EPFs) viz. Verticillium lecanii, Metarhizium anisopliaeand Beauveria bassianawith Azadirachta indicaextract (alone and in combinations) was evaluated against 2ndinstar larvae of the cotton pink bollworm, Pectinophora gossypiella(Saunders) (Lepidoptera: Gelechiidae) under controlled conditions. Results indicated that maximum mortality rate of P. gossypiellalarvae was recorded at combination of the highest conidial concentrations of V. lecanii+ M. anisopliae+ B. bassianaalong with A. indicaextract, while minimum mortality rate was recorded at A. indicaextract alone, 12 days post exposure interval. Maximum mycosis and sporulation from dead cadavers of P. gossypiellalarvae were recorded at the highest concentration of B. bassiana, while the lowest mycosis and sporulation were recorded at the highest conidial concentrations of V. lecanii+ M. anisopliae+ B. bassianaalong with A. indicaextract. Maximum percent of pupation and adult emergence in P. gossypiellalarvae was observed in the treatment, where A. indicaextract was applied alone, while the minimum percent of pupation and adult emergence was observed at the treatment combination of the highest concentration of B. bassiana+ V. lecanii+ M. anisopliaealong with A. indicaextract was applied. EPFs proved their enhanced long-term protection potential for cotton crop against P. gossypiella. A. indicaextract integrated with the EPFs can be a potential alternative to the chemicals and as an effective component of IPM program against P. gossypiella.