Bruchid pest management in pulses: past practices, present status and use of modern breeding tools for development of resistant varieties

TLDR: The present study discusses the pros and cons of different approaches for the successful management of the bruchid pests in pulses, and highlights about the integrative approach aided with molecular interventions to improve productivity by avoiding losses incurred due to bruchids, and to attain sustainable yields for major pulse crops.

Abstract: Bruchids (Callosobruchus spp.) are recognised as the most detrimental storage pest of pulses, especially in the tropics and subtropics. They invade matured pods as well as seeds during storage and, to some extent, farming fields, in turn reducing the net yield of the crops. Several approaches including cultural, biological, physical and chemical control measures have been implemented with the aim of managing these pests, but none of these have been successful across time and space. Recently, transgenic- and marker-assisted breeding approaches have appeared as promising tools for the successful management of these pests. Although some efforts have been made on the development of bruchid-resistant transgenic crops, the cultivars developed are yet to be commercialised worldwide because of various limitations. In contrast, marker-assisted breeding involving the identification of DNA-based markers linked to host resistance against bruchids, have shown some success in the quest for the development of bruchid-resistant cultivar(s). DNA markers linked to bruchid resistance have been identified in various grain legumes, particularly in the genus Vigna, and include mung bean (Vigna radiata), azuki bean (Vigna angularis), rice bean (Vigna umbellata), cowpea (Vigna unguiculata) and black gram (Vigna mungo). After their validation in different genetic backgrounds, these markers could be utilised for marker-assisted selection and breeding ventures to protect pulse crops. The present study discusses the pros and cons of different approaches for the successful management of the bruchid pests in pulses. The review also highlights about the integrative approach aided with molecular interventions to improve productivity by avoiding losses incurred due to bruchids, and to attain sustainable yields for major pulse crops.