Potential Uses of Wild Germplasms of Grain Legumes for Crop Improvement.

Nacira Muñoz,Hon-Ming Lam,Leo Kan,Ailin Liu,Man-Wah Li

doi:10.3390/ijms18020328

Abstract

Challenged by population increase, climatic change, and soil deterioration, crop improvement is always a priority in securing food supplies. Although the production of grain legumes is in general lower than that of cereals, the nutritional value of grain legumes make them important components of food security. Nevertheless, limited by severe genetic bottlenecks during domestication and human selection, grain legumes, like other crops, have suffered from a loss of genetic diversity which is essential for providing genetic materials for crop improvement programs. Illustrated by whole-genome-sequencing, wild relatives of crops adapted to various environments were shown to maintain high genetic diversity. In this review, we focused on nine important grain legumes (soybean, peanut, pea, chickpea, common bean, lentil, cowpea, lupin, and pigeonpea) to discuss the potential uses of their wild relatives as genetic resources for crop breeding and improvement, and summarized the various genetic/genomic approaches adopted for these purposes.

Highlights

Wild plants have been domesticated for thousands of years since the beginning of human civilization, as a means to ensure a stable food supply
Grain legumes were planted as companion crops of wheat and barley when agriculture began in the Near East [17,18], while some other important grain legumes have their origins of domestication in Asia and the New World
We will discuss the population approaches for dissecting the genetic variabilities and looking for important genomic regions associated with traits for nine grain legumes, especially focusing on the use of wild relatives as potential reservoirs of variability

Summary

Introduction

Wild plants have been domesticated for thousands of years since the beginning of human civilization, as a means to ensure a stable food supply. The artificial selection processes based on phenotypes (Appendix A) drove the development of new varieties with desirable features and are considered the most ancient form of plant breeding. The rationale is straightforward: wild populations must contain higher genetic variability as they were propagated in a wide range of habitats without human selection [8] Just to demonstrate this point, desirable traits such as biotic and abiotic stress resistances and special nutritional values important for crop improvement can be found in some of the wild relatives [9,10]. The seeds of grain legumes are sources of edible oils and other compounds of high nutraceutical values [16] Another unique feature of legumes is that they are able to interact with soil rhizobium to fix atmospheric nitrogen. We will discuss our perspectives on the roles of wild relatives in the new challenges that arise in agriculture

A Brief History of the Domestication of Major Grain Legumes

Plant Domestication

Traditional and Sequencing-Based Genetic Mapping Using Wild Relatives

Findings

Conclusions and Perspectives