DREB1A allows for more water uptake in groundnut by a large modification in the root/shoot ratio under water deficit uri icon


  • High water uptake, efficient conversion of water intobiomass and high harvest index are the key componentsof the yield architecture (Passioura 1977), in particularunder conditions where water deficit is common. TheInternational Crops Research Institute for the Semi-AridTropics (ICRISAT) has been involved for many years inthe development of groundnut (Arachis hypogaea)breeding lines having high water use efficiency (WUE),assessed by its major component, evapotranspirationefficiency (TE), because WUE has been identified as amajor contributor to pod yield under intermittent waterdeficit conditions (Wright et al. 1993, 1994). However, atrait-based approach using surrogates of TE as selectioncriteria to select genotypes with high TE has not provedmore successful than a yield-based approach where linesare selected based on yield under water deficit (Nigam etal. 2005). Partly it might be because of the insufficientlystrong correlation between TE and its surrogates(Krishnamurthy et al., in press). It may also be explainedby a reported negative link between TE and the harvestindex (HI), ie, genotypes with high TE usually had lowHI (Wright et al. 1991). These results demonstrate thateach component of the yield architecture cannot beaddressed independently from the other

publication date

  • 2007