Sixteen genotypes of spring wheat (Triticum aestivum L.) from different countries were evaluated for salt stress tolerance in the greenhouse under saline water irrigation. Five treatments, (T 1 ) = tap water (control), (T 2 ) = 25 mM NaCl, (T 3 ) = 50 mM NaCl, (T 4 ) = 75 mM NaCl and (T 5 ) = 100 mM NaCl were applied for each genotype grown in two seasons. Soil properties were also evaluated under these levels of water salinity. The results indicated that Number of tillers/plant, number of leaves/plant, leaves area/plant at vegetative stage, biomass, days to heading, number of kernels/spike, 1000-kerenl weight, grain yield, K + concentration and K + /Na + ratio were decreased under salinity treatments as compared with control, and hence Na + concentration was increased. Salinity levels, 25, 50, 75 and 100 mM NaCl reduced grain yield by 14.57%, 29.59%, 42.80% and 55.78%, respectively, as compared with the control treatment. After plant harvesting, soil pH decreased significantly in all soil treatments irrigated with saline water from 7.95 to 7.8. Soil electrical conductivity (EC) increased in all treatments from 3.28 to 6.22 dS/m. The irrigation with saline water caused increase in soluble cations and anions in all soil treatments. Available Mn, Zn and Cu increased in all treatments compared with control. This study suggests that wheat genotypes Shakha 93, HAAMA-14 and Shakha 8 can be selected to grow under salinity stress conditions. ª 2014 Production and hosting by Elsevier B.V. on behalf of Faculty of Agriculture, Ain Shams University.

Genetic stability and diversity are two of the key factors for the improvement of many crop plants. A major challenge for plant breeders is selection of high yielding genotype with wide adaptation. Therefore, thirty six wheat genotypes were evaluated under two locations (Sohag and Aswan, Egypt) on favorable and late sowing date during winter seasons of 2012/2013 and 2013/2014 to estimate its performance and stability parameters. The wide range of weather conditions resulted in a broad variation of mean yields, ranging from 6.59 t/ha in favorable sowing date to 4.99 t/ha in late sowing date as heat stress. The combined analysis of variance showed that the flag leaf area, days to heading, spike length, 1000-kernel weight and grain yield were significantly influenced by years, locations, sowing dates and genotypes. Mean environmental grain yield ranged from 2.70 t/ha to 9.27 t/ha. The results showed that sowing at the favorable date increased all studied traits. The 36 genotypes showed diversity for the slopes of the joint regression. Genotypes No. 5, 6, 14, 19, 20, 22, 24 and 32 exhibited stability for grain yield and useful in the breeding program in developing new wheat genotypes with tolerance to heat stress conditions. Positive correlation was found between bi and x for days to heading, spike length, number of kernels/spike, 1000-kernel weight and grain yield (0.89**, 0.50**, 0.07, 0.13 and 0.51**), respectively. This might be due to adaptation of these genotypes to wide differences in climatic conditions which prevailed at the two studied locations. The best genotypes in terms of both favorable and heat stress indicating that selecting for improved yield potential may increase yield in wide range of environments.

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Twenty four wheat genotypes (Triticum aestivum L.), differ in yield performance were grown in a randomized complete block experimental design with three replications during two seasons 2004/2005 -2005/2006 at Sohag University experimentalFarm. The genotypes were evaluated under three water regimes (control treatment (I 1 ), stress treatment (I 2 ) and high stress treatment (I 3 )) and two nitrogen fertilizer levels (70 Kg N and 100 Kg N/fed.). The analysis of variance for all parameters as affected by water regimes (I), two different N fertilizer levels (N) and the genotypes (G) and their interactions were carried and were fund to be significant. The treatments of nitrogen fertilizer (70 Kg N/fed.) and control irrigation treatment (I 1 ) over two years produced the highest grain yield from the five genotypes No. Giza 168, 9, 12, 18 and 21. While the five genotypes namely No. 5, 8, 18, 21 and 22 gave the highest yield when fertilizer with 70 Kg N/fed. with stress irrigation found to be more useful in discriminating the drought tolerance genotypes. It is concluded that the effectiveness of selection indices in differentiating drought tolerance genotypes varies with the high stress treatment. The correlations between control irrigation, drought stress, high drought stress and yield during two seasons were positive and highly significant (0.84**, 0.86** and 0.58**).