description
- Globally, diets have become dominated by a narrow range of crops. This poses threats to our food system, for example if new pathogens evolve, if heatwaves reduce yield of our staple crops, or wars and diseases prevent or change patterns of trade. Use of a wider range of other less researched crops that have known importance in local and regional food-systems would increase resilience to environmental and economic change. Only a few crops have spread far beyond their regions of origins. In environmental terms this means they have successfully transgressed the more limited ecological niche of their wild progenitor, while in cultural terms this means that a food plant has been adopted and accommodated to a range of cultural food traditions. The reasons why some crops have been more successful, in terms of becoming globally widespread and ecologically transgressive, is critical in prioritising efforts at revitalization or expansion of such crops. Crop diversity is created by both biological and cultural forces, but the cultural and historical dimensions have been neglected in the agricultural and botanical sciences. To remedy this, we aim to provide insight into the interplay of the environment, antiquity and culture on crop evolution and diversification histories. We will for the first time combine genomics, archaeology and ethnobotany (the study of plants and people) to study crop domestication and evolutionary histories, through the example of lablab or hyacinth bean. Lablab was one of a small group of five African crops that spread to South Asia in prehistory starting ~4000 years ago, marking them as especially successful at transcending their original ecologies and cultures. Legume crops (beans, pulses, including lablab) are critical for future food security as they offer high levels of protein and other nutrients, yet are far less studied than cereals (wheat, corn, rice). They also are nitrogen-fixing, requiring less use of fertilizers. Legumes of tropical origins, like lablab, are especially important for food security and sustainability in large parts of the developing world. Lablab is one of the world's most adaptable crops, grown from very dry to wet tropical regions, and has different uses and forms resulting from cultural selection and environmental adaptation. It is used in different parts of the world as a dried bean, fresh beans, fermented paste, and for its pods and leaves as a vegetable, especially in east and southeast Asia; in many farming systems it is also grown as animal fodder. Our overarching aim is to resolve the genetic, ecological, and cultural basis of crop evolutionary processes, through determining: 1) the domestication, diversification, and dispersal histories of lablab, and (2) how varietal groupings, traits and genes are linked to environmental adaptation and/or human selection Existing evidence supports two domestications in East Africa, but details are lacking on subsequent dispersal routes within Africa, and across India. We will expand this through additional genomic analyses, including from new targeted collections with partners. Archaeobotanical records will document seed evolution and place this in time and space, and ethnobotanical and colonial archive sources will document cultural uses and changes in recent centuries. Taken together we will reconstruct processes of diversification and adaptation over the long-term, as well as diversity loss, contributing towards identifying where conservation is urgent, and where breeding efforts and revitalization are most promising, including for future climate resilience.