Evaluation of salt tolerance in wheat genotypes on growth and carbon isotopes discrimination technique

Studies were conducted in green house to select suitable salt tolerant wheat genotypes on the basis of growth performance and carbon isotopes discrimination (cid) technique. nine newly developed double haploids (dh) wheat genotypes were tested under gravel culture,along with salt tolerant (lu-26s) and high yielding (sarsabz) checks. the crop was irrigated by non-saline (control) and saline (12ds/m) water and raised up to maturity,growth parameters (i.e. plant height,plant biomass,productive tillers,spike length,number of spiklets/spike,number of grains / spike,grain weight/ spike and grain yield/ 15 plants) were recorded after harvesting. plant samples (straw) were collected and were analyzed for carbon isotopic ratio (c12/c13) from iaea laboratories vienna austria. the data showed that there was significant decrease in all the growth parameters due to salinity. on the basis of performance in different growth parameters it was found that wheat genotypes v3-dh,v9-dh,v10-dh,v13-dh,and lu-26s had good response at 12dsm-1,thus can be categorized as better performing genotypes. studies on carbon isotopes discrimination (cid) showed a decreasing trend under salinity. mean cid values were 20.86 and 17.49‰ under two environments (non saline and saline,respectively),showing an overall 19% decrease under salinity. generally the wheat genotypes having higher grain yield also had high carbon isotopes discrimination (cid). the relationship between grain yield and cid (∆) was positive (r2 = 0.695). the genotypes v10-dh,v13-dh with lower decrease in cid (i.e. 1.2 & 11.0%,respectively),also had high grain yield under salinity. therefore the studies suggest that we can include cid technique as one of the selection criteria for salt tolerance. © 2015,pakistan botanical society. all rights reserved.