Estimation of Some Genetic Parameters for phenological, Morphological and productivity Traits in Two Bread Wheat Crosses

The experiment was grown in a Randomized Complete Blocks Design with three replications during two seasons. Generations means analysis method was used to study the genetic parameters for number of days to heading, number of days to maturity, plant height, number of spikes per plant, number of grains per spike and grain yield per plant of two bread wheat crosses Triticum aestivum L. (Gairwel7 x Douma4), (Azaz1 x Soued), Results have shown that both additive and dominance genetic effects were high significant in most evaluated traits, with predominance of the dominance genetic effects’ values. Also, epistatic genetic effects have contributed to inheritance of most studied traits. The signs of dominance and dominance x dominance were opposite in most examined traits indicating duplicate epistasis for all studied traits of the first cross and for number of days to maturity, plant height and number of grains per spike of the second cross, that indicates that the selection for these traits should be delayed after several generations. High phenotypic variations were composed of high genotypic variations and less of environmental variations, indicating the presence of high genetic variability for different traits and less influence of environment. Highly significant heterosis relative to mid and better parents in F1 was recorded for most characters, accompanied with inbreeding depression for all traits in F2. Narrow sense heritability and genetic advance were low in most cases due to the dominant of non-additive genetic action in controlling the genetic variation of the most studied traits.

Genetic variance, heritability, correlation and path coefficient analysis in some Bread Wheat Crosses (Triticum aestivum L.)

The present investigation was conducted during 2010/2011 and 2011/2012 growing seasons at Karahta station for field crops research, General Commission for Scientific Agricultural Researches (G.C.S.A.R.), Syria. Forty five hybrids F1 produced using a half diallel cross among ten bread wheat (Triticum aestivum L.) genotypes, in 2010/2011 season, were evaluated during 2011/2012 season in order to study som of the genetic parameters for grain yield per plant, its components, some morphophysiological and quality traits to determine the basic criteria for selection.

A Study of Yield, its Components, and Some Technological Characteristics of Local and Introduced Varieties of Bread Wheat

Eight varieties of soft wheat T.aestivum L. were used in the study, four of which were local (sham 6, sham 8, sham 10 and bohoth 4) and four introduced varieties obtained from the Scientific Agricultural Research Center (Tugela, Betta, Bezenchukskaya98 and saratovskaya210) and grown during the periods (2011-2012 and 2012-2013) at Qabu Al Awwamiyya near Lattakia City. The following readings were taken for the studied varieties (yield, plant height, spike length, number of spikelets per spike, weight of 1000 grains, protein content proportion of gluten, ash, and moisture content). Data was analyzed statistically using an analysis of variance. The results showed significant differences between the local and introduced varieties on the one hand, and between the varieties themselves on the other hand. Local varieties were better than the introduced varieties with regards to the protein content, moisture content, proportion of gluten, yield, spike length, number of spikelets per spike, and the 1000-grain weight. The introduced varieties however were superior in plant height and ash. The best varieties among local varieties were (Sham 6 and Sham 10), and Betta among the introduced ones.

The effect of salinity on proline and carbohydrate contenets in three bread wheat genotypes (Triticum aestivum L.) in vegetative growth stage in hydroponic cultures

This study was carried out in 2009-2011, in the laboratories of science faculty - Tishreen University. The seeds of three genotypes: Sham8, Sakha8,AUS 29639 of bread wheat were planted in hydroponic cultures irrigated with Hoagland liquid in a growth chamber to compare the effect of three salt concentrations (0, 100,200 mm of NaCl) on proline and carbohydrate contents in three growth stages 21, 28, 35 of the experiment. There was an increase of proline and carbohydrate contents in all cultivars with increased salinity during the three growth stages of plants. Proline contents increased in Sham8 with low rates compare with Sakha8, AUS 29639. It increased in Sakha8 with the increase of salinity which reached 348% in the third growth stage in concentration 200 mm NaCl, while Proline concentration reached the highest value in AUS 29639 (524%). The carbohydrate content reached the highest value in Sakha8 in NaCl concentration 200 in the first growth stage (238070%) compared with the control, and (204.34%) in third stage in NaCl concentration 200mM compare with the control. The results of the study indicate the superiority of Sakha8, AUS 29639 in salt tolerance through accumulating suitable rates of proline and carbohydrates. AUS 29639 was more resistant to salt stress than Sakha8. We may use these results later in other physiological and genetical studies.

Estimate Some Genetic Parameters for Grain Yield and Some of Its Contributing Traits in Bread Wheat Crosses

The Experiment was conducted during the successive growing seasons (2013/2014- 2014/2015) where half–diallel hybridization was conducted between eight genotypes of bread wheat.

Using of Photosynthetic electron transport as an indicator of photosynthesis efficiency

Photosynthetic transport was studied as an indicator of photosynthesis efficiency in two bread wheat cultivars (ACSAD 899, ACSAD 1059) under the influence of one of the salt stress. This study was carried out in sand cultures irrigated with nutrient solution in a growth chamber, and 14 days seedlings were treated with 100 mM of sodium chloride. Later the electron transport rates in those plants thylakoids were measured in 21, 28, 35 days of the experiment. Electron transport rates decreased in ACSAD 899 and reached 57% in the last day of the experiment, while it was 24.6% in ACSAD 1059. The decrease in photosynthetic electron transport rate leads to a decrease in the reduction rate of CO2 and the plant productivity as a consequence. Therefore, it could be used as criterion to express photosynthesis.

Response of Bread wheat to potassium nutrition: some growth, productivity and efficiency parameters

A pot experiment was conducted in a green house at Tishreen University in which bread wheat (cv. Sham 6) was grown at different levels of potassium nutrition (K0=0, K1=25, K2=50, K3=75, K4=100, K5=150) mg k/kg soil. The increase in potassium fertilization rates led to a significant increase in the number of total tillers and fertile tillers on the expense of non-fertile tillers. This was accompanied with no significant increase in number of main stems spikes grains, while the tillers spikes of the first level of potassium application (K1) was higher significantly compared to control treatment (K0). The same treatment (K1) gave the best weight of grain on the main stems spikes and tillers. The productivity of grain yield increased (but non-significantly) with increasing the level of potassium fertilization. The highest yield value was obtained in K5 treatment which was 13933 kg /ha. This productivity constitutes a rate of increase 18% compared to the control treatment (K0). The calculation of Agronomic Efficiency (AE) showed a high value of (about 13 kg seeds/kg of K fertilizer added) in the K1 treatment, and thereafter, AE gradually decreased with potassium fertilization to reach about 6 kg grain/kg K fertilizer for K4 and K5 treatments (100 and 150 mg K/kg).

Genotype x Environment Interaction and Yield Stability Analysis of Some Bread Wheat (Triticum aestivum L.) Genotypes at Different Locations in the Syrian Coast

Eleven genotypes of Bread Wheat (Triticum aestivum L.) were tested at three diverse locations in the Syrian Coast during the 2015-2016 season under rain-fed conditions to assess these genotypes and to study the Genotypes x Environments Interactions, and yield stability across environments using 5 statistical measures of stability:{ X¯i, bi, and i according to Eberhart and Russell (1966), Stability Variance Index (2 i) according to Wricke and Weber (1980), Ecovalance Stability Index (Wi) according to Wricke (1962)}. Genetic material included 5 promising lines and 6 local varieties (provided by ACSAD and GCSAR).The experiment was designed using randomized complete block design with three replications, statistical data analysis was done, and least significant difference (L.S.D) test at 5% was applied for comparison of means. Significant differences were observed among bread wheat genotypes for grain yield (ton/ha), combined analysis of variance of grain yield across the three environments showed significant mean squares due to genotypes, environments and genotypes x environments interaction, suggesting differential responses of genotypes across studied environments and validity of stability analysis. Stability analysis for grain yield revealed that; the promising line ACSAD-1147 and Doma6 were more stable than other genotypes. Due to they had superior ranks for both average yield over environments and yield stability, which reveals the importance of these genotypes to reach varieties that combine relatively high yield and better stability in any future breeding programs.