Molecular breeding for drought tolerance: Progresses, issues, orientations

Water deficit, often referred to as “drought”, is the most prominent abiotic stress, severely limiting crop yields and opportunities to improve livelihoods of poor farmers in the semi-arid tropics. For example, it is estimated that annually, drought causes US$ 520 M losses in groundnut alone (Subbarao et al., 1995). One of the major research objectives at ICRISAT is to exploit modern science techniques to develop crops that are more resilient to low and erratic rainfall patterns. Conventional breeding of early maturing varieties, capable to escape drought and mature before water deficit becomes too severe, has been a common approach in most mandate crops of ICRISAT. However, substantial variation for drought tolerance, beyond earliness has not been identified nor utilized extensively. However, conventional, yieldbased selection for drought tolerance.......