Ancient orphan legume horse gram: a potential food and forage crop of future

Abstract

Tailoring crops to withstand rising temperature and declining precipitation may be unrewarding, therefore the potential of alternative undervalued crops such as horse gram can be explored for safeguarding food and nutritional security with health benefits in the era of climate change. Horse gram [Macrotyloma uniflorum (Lam.) Verdc] under the family Fabaceae, has been cultivated for food, folklore medicine and fodder mainly by rural and tribal communities since prehistoric times in Asian and African countries. This valuable ancient legume not only offers diversification and resilience to agro-ecosystems but it also possesses high adaptation in risk-prone traditional farming systems in marginal environments of semi-arid and arid regions. Being a nutrient dense legume with remedial health-promoting effects due to the presence of various bioactive compounds, it is suitable for the development of functional food as well as for addressing micronutrient deficiencies among poor rural communities. Despite its enormous potential and a growing awareness about the utility of this underutilized crop for future climate adaptation and human well-being, this legume continues to be seriously neglected and labelled as "food of the poors". India is the major producer of horse gram and presently, cultivation of horse gram remains confined to small-scale farming systems as an inter- or mixed crop. This crop is alienated from mainstream agriculture and relegated to a status of "underutilized" due to its limited competitiveness as compared to other commercial crops. Besides a scanty basic research on this crop, no attention has been paid to the factors like improvement of plant type, yield improvement, processing, value addition to suit consumer needs and reduction of anti-nutritional factors, which restricted the diffusion of this crop outside its niche area. The present review therefore is an attempt to compile the meagre information available on crop history, evolution, genetic enhancement, nutritional and health benefits to make the crop competitive and revitalize horse gram cultivation.

Keywords: Breeding; Domestication; Genetic and genomic resources; Macrotyloma; Nutraceutical properties; Nutritional value.