Salinity is an increasing stress with adverse effects on farming systems, and especially those in arid and semi-arid regions of the world, and in Australia. Chickpea is a salt sensitive cool-season legume crop that has been grown in semi-arid regions as a major source of protein for humans. Salt tolerance in chickpea has received relatively little attention, as previous studies indicated low levels of salt tolerance in chickpea. A recent large scale screening at ICRISAT, however, revealed 5 fold variation in yield under salinity. Information on the physiological basis of ion regulation in plant tissues was contradictory, and no information was available on the inheritance of key agronomic and physiological traits and identification of genomic regions for salt tolerance in chickpea. Thus, this thesis had the following objectives; 1a) study the sensitivity/tolerance of vegetative and reproductive growth stages with an altered treatment at flower initiation stage, 1b) assess ion toxicity in different tissues like shoot, root and floral structures; 2) study the type of gene action involved in controlling different traits under salinity using ‗Generation mean analysis‘ from six populations (P1,P2, F1, F2, BC1P1 and BC1P2). Parents were selected based on seed yield in two years of screening using 80 mM NaCl in pots of soil; 3) Development of F8 RILs (ICC6263 x ICC1431) and, construct a linkage map to identify the quantitative trait loci (QTL) for various agronomic traits under saline conditions. Results showed that both vegetative and reproductive phases were sensitive to salt and high ion concentrations (Na+ and Cl-) were observed in floral structures along with shoot and root. Pollen viability was not affected in plants grown in saline treatment, but in vitro germination of pollen was reduced significantly even at 40 mM NaCl in the germination medium.
|Qualification||Doctor of Philosophy|
|Publication status||Unpublished - 2010|