Pursuing greener farming by clarifying legume-insect pest interactions and developing marker-assisted molecular breeding

Legumes are important for both food security and sustainable agriculture. Given their relatively high protein content, more than 700 million people worldwide rely on them as food or poultry feeds. They are also important in intercropping systems for improving soil quality, due to their nitrogen-fixing ability. One major challenge to the yield of legumes is infestation by insect pests and pathogens both in the field and during storage. Most farmers have responded by planting resistant strains of legume crops and spraying them with insecticide and fungicide. Nevertheless, the continuous use of biocides, despite their cost-effectiveness, results in resistance development by the pests and pathogens, and raises environmental safety concerns for both humans and off-target beneficial species of insects and microbes. In this review, we discuss the most up-to-date thinking on the interactions between legumes and their insect pests and current farming practices, explain the latest techniques used in identifying molecular markers to aid in the breeding of insect-resistant cultivars, and highlight areas that require further development for effective and ecofriendly integrated pest management.