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Genetic variability of some agronomic traits were investigated in 60 tetraploid wheat accessions (Triticum turgidum L. ssp) under rainfed conditions. The results indicated the presence of sufficient variability for all measured traits.The highest phenotypic and genotypic coefficient of variation was recorded for yield and awn length. High heritability coupled with high genetic advance and high expected response to selection recorded for thousand-grain weight, awn length, and the number of grains per spike. Cluster analysis grouped the 60 wheat genotypes into five clusters. Clusters are relatively formed according to the geographical origin of the genotypes. Cluster III carried entries having the best combinations for all the traits; in which genotypes PI 127106, PI 192658, PI 29051 and PI67343 can represent an important reservoir of useful genes for the development of new wheat cultivars. Thousand-grain weight, biomass, awn length and harvest index could be used as a selection criterion for hybridization programs in the future. Highlights - The genetic variability of 9 traits of 60 wheat varieties was investigated. - There was great variability among wheat genotype for all measured traits. - There were wheat varieties shows highest phenotypic and genotypic coefficient of variation. - Some wheat genotypes may be desired allele reservoirs. - Some traits can be an alternative in wheat selection.

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We evaluated the phenotypic stability of 23 durum wheat genotypes using various stability parameters to select genotypes that have both high performance and stability. The research was conducted in four locations by randomized complete block design with four replications in each location during the 2008-09 and 2009-10 cropping seasons. The objectives were to assess genotype-environment interactions (GEI), determine stable genotypes, and compare the mean grain yield with the stability parameters. To quantify yield stability, seven stability statistics were calculated (bi, Pi, ASVi, CVi, S 2 di, S 2 i and W 2 i). The grain yields of all genotypes were significantly affected by environment, which accounted for 88.2 % of the total variation, whereas genotype and genotype-environment interaction accounted for 2.9 % and 8.9 %, respectively. The genotype mean yield significantly positively correlated with the regression coefficient (bi) and environmental variance (S 2 i). The correlation analysis also separated the Pi, bi and S 2 i methods, which correlated with the mean yield, and the ASV, W 2 i and S 2 di methods, where the phenotypic stability seems to be measured independently on the yield. Genotypes Bel, Amg, Miki, Bss and Msb were more stable by most statistics used. Miki, Amg and Msb were the best genotypes demonstrating high average yields and high stability of performance across the test locations.

Water stress is the most important problem in plant growth and development. Greenhouse trial is carried out on 2 durum wheat (Triticum durum Desf) genotypes (MBB and WAHA), to evaluate the effect of water stress on the biochemical content of leaves, and the possibility of reducing this effect by applying a growth regulator Indole-3-acetic acid (IAA) by seeds soaking and foliar spraying. Water stress causes a large accumulation of proline and soluble sugars and a decrease in the chlorophyll content of the leaves. The results obtained show that the effect of the hormone on the above-mentioned parameters is different according to the genotype and the mode of treatment, as well as the growth phase of the plant, without being able to promote application by soaking or spraying. The application of IAA has relatively reduced the effect of water stress by promoting the synthesis of proline and soluble sugars as osmotic regulators, and by increasing the chlorophyll content of the leaves. proline and soluble sugars concentrations showed negative and significant correlations with those of total chlorophyll. Our present study highlights some biochemical responses of plants to tolerate a water deficit and the possible involvement of exogenus application of IAA, as a phytohormone, in these regulatory mechanisms.