Transgenic strategies for improved drought tolerance in legumes of semi-arid tropics. uri icon

abstract

  • Water deficit is the most prominent abiotic stress that severely limitscrop yields, thereby reducing opportunities to improve livelihoodsof poor farmers in the semi-arid tropics (SAT) where most of thelegumes, including groundnut and chickpea, are grown. Sustainedlong-term efforts in developing these legume crops with betterdrought tolerance through conventional breeding have been metwith only limited success mainly because of an insufficient understandingof the underlying physiological mechanisms and lack ofsufficient polymorphism for drought tolerance-related traits. Exhaustiveefforts are being made at the International Crop ResearchInstitute for Semi-Arid Tropics (ICRISAT) to improve crop productivityof the SAT crops by comprehensively addressing the constraintscaused by water limitations. The transgenic approach has beenused to speed up the process of molecular introgression of putativelybeneficial genes for rapidly developing stress-tolerant legumes.Nevertheless, the task of generating transgenic cultivars requiressuccess in the transformation process and proper incorporation ofstress tolerance into plants. Hence, evaluation of the transgenicplants under stress conditions and understanding the physiologicaleffect of the inserted genes at the whole plant level is critical. Thisreview focuses on the recent progress achieved in using transgenictechnology to improve drought tolerance, which includes evaluationof drought-stress response and protocols developed for testingtransgenic plants under near-field conditions. A trait-based approachwas considered, in which yield was dissected into components

publication date

  • 2009
  • 2009