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Abstract Yard-long bean is one of the most popular vegetables, and is extensively grown in Southeast Asian countries including Cambodia. However, yard-long bean production is severely affected by a plethora of insect pests and diseases, and application of chemical pesticides is the main mode of pest control. In order to reduce the over-reliance on chemical insecticides, we evaluated the effectiveness of microbial pesticides (Bacillus thuringiensis and Metarhizium anisopliae formulations), and neem leaf extract alone and in combination (as an IPM package) against aphids, thrips and pod borer on yard-long bean in three different provinces of Cambodia from 2015 to early 2018. The bio-pesticides reduced the incidences of thrips (Megalurothrips usitatus), and the infestation by the aphid (Aphis craccivora) and the pod-borer (Maruca vitrata) to the levels equivalent to chemical pesticide (abamectin) during trials in 2015 and 2016. Although the yield was significantly higher in bio-pesticide treated plots than untreated plots in 2015, the yield did not differ significantly among the treatments in 2016 trials. Multi-location trials during 2016–2018 confirmed that the performance of the IPM package was on par with Farmers' practice (calendar-based application of chemical pesticides) in reducing the infestations by target pests, without compromising yield. Hence, the IPM package can be a better alternative to chemical pesticides in managing the key insect pests on yard-long bean in Cambodia. Highlights • Aphid, thrips and pod-borer are the major pests causing significant yield losses in yard-long bean in Cambodia. • So far, there have been no valid alternatives to chemical pesticides. • On station and on-farm trials confirmed the effectiveness of bio-pesticides and an IPM package. • This is the first report of an effective IPM package for yard-long bean in Cambodia. [ABSTRACT FROM AUTHOR]

Chinese mustard is an important leafy vegetable, which is grown in about 5% of total vegetable area in major vegetable producing provinces of Cambodia. Production of Chinese mustard is severely hampered by the insect pests especially lepidopteran caterpillars and the flea beetles. Chinese mustard producers predominantly rely on the application of chemical pesticides for management of these pests and produce blemish free produce. In order to reduce the extensive reliance on pesticides, efficacy of biopesticides (Bacillus thuringiensis and Metarhizium anisopliae formulations, and neem extract), either alone and in combination (as an IPM package) against diamondback moth, common armyworm, cabbage webworm and striped flea beetle on Chinese mustard was assessed in three different provinces of Cambodia during 2015–2018. The bio-pesticides reduced the incidence of diamondback moth, common armyworm, cabbage webworm and the damage by striped flea beetle to the levels equivalent to chemical pesticide (abamectin) during trials in 2015 and 2016. Although the yield was significantly higher in bio-pesticide treated plots than untreated plots in 2015, the yield did not differ among the treatments in 2016 trials. Multi-location trials during 2016–2018 confirmed that the performance of the bio-based IPM package was on par with farmers' practice of calendar-based pesticide application in reducing the damages by target pests, leading to significant yield gains. Hence, the bio-based IPM package can be a better alternative to chemical pesticides in managing the key insect pests on Chinese mustard in Cambodia. • Insect pests such as diamondback moth, common armyworm, cabbage webworm and flea beetles are major production constraints in Chinese mustard. • Pesticides are the main control option adopted and use of bio-pesticides is highly uncommon in Cambodia. • An integrated pest management strategy based on use of Bacillus thuringiensis , Metarhizium anisopliae and neem was developed for Chinese mustard. • Multi-locational on-station and on-farm trials confirmed the effectiveness of bio-based IPM package as an effective alternative to chemical pesticides. [ABSTRACT FROM AUTHOR]