Genotypic variation in root and shoot growth traits of wheat seedlings and its association with salt tolerance

To improve crop yields and increase of production performance in marginal areas, the use of genetic potential of crops in terms of morphological and physiological characteristics can lead to yield improvement and increase of production performance in areas with saline water and soil salinity. In order to evaluate genotypic variation in growth and physiological traits of different bread wheat cultivars at vegetative stage, a greenhouse experiment was carried out with a factorial experiment based on completely randomized design in three replications, growing in PVC tubes. The results showed a genetic diversity in root and shoot growth and physiological response to saline stress. Salinity was caused to decease root system growth such as seminal axil root length, number of roots and distance between distal branch root by ~35, 30 and 40%, respectively, for all cultivars when compared with control. Relative water content, stomatal conductance, shoot dry weight and relative growth rate was decreased under salt stress by ~7, 80, 40 and 26%, respectively, when compared with control, but chlorophyll index was increased. The values of reduction for root and shoot growth and physiological traits were less for salt tolerant cultivars than sensitive ones. Difference in salt tolerance in terms of shoot growth and physiological responses was consistent with root growth response. A genetic variability for salt tolerance within wheat cultivars, indicating the existence of opportunities to improve salt tolerance in wheat through selection and breeding.