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Relationships Between Cold Tolerance, Grain Yield Performance and Stability of Durum Wheat (Triticum durum Desf.) Genotypes Grown at High Elevation Area of Eastern Algeria  [PDF]
A. Mekhlouf,F. Dehbi,H. Bouzerzour,A. Hannchi
Asian Journal of Plant Sciences , 2006,
Abstract: To increase grain yield in the North African high plateaus, selection of durum wheat (Triticum durum Desf.) was accompanied by an early heading for effective utilization of the limited soil moisture and to escape terminal drought and heat stresses. Early genotypes suffer however seriously from low temperature damage during cold season. Developing cultivars resistant to low temperature stress appears critical to avoid crop failure and to stabilize grain yield. The objectives of the present study were to evaluate the genotypic variability for resistance to low temperatures using artificial tests and to investigate the relationship between the results of such tests and the agronomic performance and stability of a field grown set of durum wheat (Triticum durum Desf.) genotypes. The artificial laboratory tests employed enabled genotypes to be differentiated on the basis of their cold tolerance, results suggest that genotypes which possess the ability to cold acclimate during winter retain this feature until the booting stage. Means of agronomic traits varied significantly between seasons and genotypes, indicating the presence of significant genotypic variability and differential responses to the growth conditions experienced. No consistent relationships, between the tolerance to low temperatures and agronomic performances, were found due to the confounding effects of terminal heat and drought stresses, acting on the same yield components as the cold stress. Early, freezing tolerant and above average yielding cultivars were identified which serve as genetic source to improve tolerance to low temperatures in short cycle genetic background.
Selection criterion for improved grain yields in Ethiopian durum wheat genotypes
A Gashaw, H Mohammed, H Singh
African Crop Science Journal , 2007,
Abstract: Wheat (Triticum durum Desf.) is the most important cereal crop grown in the intermediate and highland areas of northeastern Ethiopia. Durum wheat dominates in these areas where water logging is the major production constraint. Because of the predominant problem of water logging coupled with other various biotic and abiotic production hobbling factors, the average productivity of wheat in the northeastern region never exceeds 8.4 ha -1, which is below the national average of 14.4 ha -1 (ECSA, 2002). Screening of wide durum wheat germplasm has been undertaken to improve durum wheat grain yield. But, selection based on the performance of grain yield alone, a polygenically controlled complex character, is usually not very efficient. An experiment was conducted at Geregera testing site of Sirinka Agricultural Research Centre, during the 2003-cropping season with the objective of estimating the associations between yield and yield-related traits and to identify direct and indirect effects of characters for durum wheat grain yield improvement. The experimental material consisted of 44 indigenous durum wheat genotypes, which are randomly taken from the indigenous germplasm collections. Mean sum of squares for all the characters considered showed highly significant differences (P<0.01) indicating the presence of adequate variability. Grain yield had strong positive correlations (P<0.01) with plant height, number of kernels spike-1, grain yield plant-1, biological yield and thousand-kernel weight. On the contrary, grain yield had strong negative correlation (p< 0.01) with days to heading suggesting that the usefulness of selecting early heading genotypes with long grain filling period in improving grain yield. The results of genotypic correlation indicate that maximum positive direct effect on grain yield was exerted by biological yield (1.08) followed by days to maturity (0.91) and harvest index (0.69). While, maximum negative direct effects were exerted by days to heading (-0.72) and grain filling period (-0.52). Therefore, days to heading, biological yield and harvest index could be used as an indirect selection criterion for better grain yield. Thus, selecting early heading genotypes having high biological yield and harvest index could improve grain yield.
Relationships Between Grain Yield Performance, Temporal Stability and Carbon Isotope Discrimination in Durum Wheat (Triticum durum Desf.) Under Mediterranean Conditions  [PDF]
A. Adjabi,H. Bouzerzour C. Lelarge,A. Benmahammed,A. Mekhlouf
Journal of Agronomy , 2007,
Abstract: The experiment was conducted during six cropping seasons (1997/98 to 2002/03), with the objective to study the relationships between grain yield performance, temporal stability and carbon isotope discrimination of durum wheat (Triticum durum Desf.) genotypes grown under semi-arid conditions of the eastern highlands of Algeria. The results indicated significant season and genotype x season interaction for grain yield and a non significant genotypic main effect. Mrb5 cultivar out yielded the evaluated entries during three out of six cropping seasons, Cyprus 1, Bicre and Daki were the top-yielding genotypes in two seasons and Waha, Belikh 2 and Heider/ Martes// Huevos de Oro, were high yielding during only one cropping season. Heider and Mrb16 showed a relatively high grain yield temporal stability, Derraa had the lowest value. The results of the present study indicated that grain yield measured during six cropping seasons was not significantly correlated with Δ13C measured during one season. This suggested that carbon isotope discrimination could not be suggested as an indirect selection criterion to screen durum wheat genotypes for water use efficiency under the Mediterranean climate of the high plateaus of Algeria.
Effets de la vitesse et de la durée du remplissage du grain ainsi que de l'accumulation des assimilats de la tige dans l'élaboration du rendement du blé dur (Triticum durum Desf.) dans les conditions de culture des hautesplaines orientales d'Algérie
Bahlouli F.,Bouzerzour H.,Benmahammed A.
Biotechnologie, Agronomie, Société et Environnement , 2008,
Abstract: Effects of speed and the duration of grain filling and the accumulation of the assimilates of the stem in developing the durum wheat yield (Triticum durum Desf.) in the culture conditions of the high plains of eastern Algeria. The present study was led on the experimental site of station ITGC in Setif. The objective is to determine the differences of duration and speed of filling and the contribution of the assimilates of the stems to the yield of 5 durum wheat genotypes (Triticum durum Desf.). The year effect is significant, what explains the fluctuation of the conditions of one growth year to another. The grain yield is associated to the great quantity of assimilates stored and transferred from the stems to the grain filling. The Mbb genotype which has an important stem height transfers more assimilates. The genotypes ADS497 and Deraa present large standard leaves. The beginning of the active phase of the grain filling corresponds to the beginning of the foliar senescence. Mbb presents a slower foliar drying rate, the speed of drying stationary recorded by ADS497 is of -0.5957 cm2 per day. The speed of grain filling is negatively related to the duration of filling. The participation of the assimilates coming from the stem decreases when the environment allows the expression of a better grain yield.
Ultrastructure and biochemical traits of bread and durum wheat grains under heat stress
Dias, Ana S.;Bagulho, Ana S.;Lidon, Fernando C.;
Brazilian Journal of Plant Physiology , 2008, DOI: 10.1590/S1677-04202008000400008
Abstract: the yield and grain quality (as well as technological traits) of two heat-stressed genotypes of bread (triticum aestivum l.) and durum wheat (triticum turgidum subsp. durum) having different tolerance to high temperatures after anthesis were investigated. heat stress, during grain filling, triggered grain shrinkage with a reduced weight and ultrastructural changes in the aleurone layer and in the endosperm cells. heat stress also decreased the sedimentation index sds, an effect associated with increased protein content in the grain but with decreased levels of essential amino acids. although the responses to heat stress were similar among the triticum genotypes, it is further suggested that during grain filling, high temperatures might affect gluten strength, diminishing the wheat flour quality.
The occurrence of fungi on roots and stem bases of common wheat (Triticum aestivum ssp. vulgare L.) and durum wheat (Triticum durum Desf.) grown under two levels of chemical protection
Irena Kiecana,Leszek Rachoń,El?bieta Mielniczuk,Grzegorz Szumi?o
Acta Agrobotanica , 2011, DOI: 10.5586/aa.2011.036
Abstract: Investigations were carried out in 2007-2009 on the plots of the Felin Experimental Station belonging to the University of Life Science in Lublin. The studies comprised two cultivation lines of durum wheat (Triticum durum L.): STH 716 and STH 717, as well as the 'Tonacja' cultivar of common wheat (T. aestivum ssp. vulgare L.). Two levels of chemical protection were applied in the cultivation: minimal and complex protection. Infection of wheat roots and stem bases was recorded in each growing season at hard dough stage (87 in Tottman's scale, 1987). After three years of study, the mean disease indexes for the analyzed wheat genotypes in the experimental treatment with minimal protection were 31.13, 30.43 and 38.83 for, respectively, the 'Tonacja' cultivar and the cultivation lines of T. durum STH 716 and STH 717. In the experimental combination with complex protection, after three years of study the disease indexes ranged from 25.26 (T. durum STH 716) to 30.83 (T. durum STH 717). The results of mycological analysis of diseased plants showed that Fusarium spp., especially F. culmorum, F. avenaceum as well as Bipolaris sorokiniana and Rhizoctonia solani, caused root rot and necrosis of wheat stem bases. The analyzed chemical protection levels did not significantly influence grain yield of the investigated genotypes of T. aestivum and T. durum.
Study of Genetic Architecture of Some Important Agronomic Traits in Durum Wheat (Triticum durum Desf.)
Muhammad Kashif,Javed Ahmad,Muhammad Aslam Chowdhry,Khalida Perveen
Asian Journal of Plant Sciences , 2003,
Abstract: Gene action and components of variance analysis were made in a 6X6 diallel cross in durum wheat (Triticum durum Desf.). Additive gene effects were more important for all the traits. Complete dominance for yield plant-1 and spike length and over dominance for tillers plant-1 was observed. While plant height, spikelets spike-1, grains spike-1 and 1000-grain weight exhibited partial dominance. Dominant alleles were more frequent in parents for all characters except plant height and 1000-grain weight. Durum wheat genotypes, Altar 84 and Bittern "s" showed relatively higher combining ability.
Selection of High Yielding and Risk Efficient Durum Wheat (Triticum durum Desf.) Cultivars under Semi-arid Conditions  [PDF]
F. Bahlouli,H. Bouzerzour,A. Benmahammed,K.L. Hassous
Journal of Agronomy , 2005,
Abstract: An experiment was conducted, during the successive cropping seasons 1997/98 to 2002/03, to study grain yield performances and yield stability of 10 durum wheat ( Triticum durum Desf.) varieties in order to identify the productive, stable and risk efficient genotypes for a subsistence agriculture. Grain yield analysis showed high seasons and season x genotype interaction effects reducing the genotypic main effect. Regression coefficients, variance across seasons and safety-first indices based on these parameters classified differently the tested genotypes for stability and risks of giving a low yield under stress. FW index was correlated with grain yield, regression coefficient and the mean square of the contribution of the test cultivar to GxS interaction. The EV index did not show a significant correlation with the measured variables. It was possible within the set of genotypes tested to select high yielding and risk efficient cultivars compared to the check cultivar Mohammed Ben Bachir.
Genetic divergence in selected durum wheat genotypes of Ethiopian plasm
A Gashaw, H Mohammed, H Singh
African Crop Science Journal , 2007,
Abstract: Wheat of both the tetraploid (Triticum durum Desf.) and hexaploid (Triticum aestivum L.), is the most important cereal crop in Ethiopia, ranking third in total production (17%) next to maize (Zea mays L.) and tef (CSA, 2002). Wheat covers a total arable land of 110,434 ha with average productivity of about 8.4 qt ha-1, which is below the national average (14.4 qt ha-1). A field experiment was conducted at the Sirinka Agricultural Research Centre, northeastern Ethiopia, to estimate the genetic divergence among indigenous durum wheat (Triticum durum Desf.) genotypes of diverse origin, and clustering them into homogenous groups for the hybridisation programme. Genetic divergence analysis was done based on multivariate analysis using Mahalanobis’s D2 statistic, which grouped the durum wheat genotypes into ten clusters. The highest inter-cluster distance was between clusterll and cluster-lll (D2 = 57.15). There was no correspondence between geographic and genetic distances, i.e., germplasms, collected from the same geographic area were placed into different cluster groups and those collected from different geographic regions were placed into the same cluster. The presence of significant genetic variability among the evaluated durum wheat genotypes suggests an opportunity for improvement of grain yield through hybridisation of genotypes from different clusters and subsequent selection from the segregating generations.
The Effect of Drought Stress on Grain Yield, Yield Components and Some Quality Traits of Durum Wheat (Triticum turgidum ssp. durum) Cultivars  [cached]
Hasan KILI?,Tacettin YA?BASANLAR
Notulae Botanicae Horti Agrobotanici Cluj-Napoca , 2010,
Abstract: Drought, one of environmental stresses, is the most significant factor restricting plant production in majority of agricultural fields of the world. Wheat is generally grown on arid–agricultural fields. Drought often causes serious problems in wheat production areas. A field study was conducted on clay-silt soil, in the Research Field, Southeastern Anatolia Agricultural Research Institute, in Diyarbak r during 1999-2000 growing season in order to evaluate genotypes for yield, yield components and some quality traits. Fourteen wheat (Triticum turgidum ssp. durum) cultivars were grown under well watered and naturally drought conditions. Morphological traits were measured at anthesis and yield, yield components and quality traits were evaluated at ripening time. The flowering period was negatively associated with grain yield, while grain filling period, chlorophyll content, number of grains per spike and spikelets per spike were positively associated with grain yield under drought conditions. Moreover, the number of days to maturity was negatively associated with Drought Susceptibility Index (DSI), while Spike length was positively associated to DSI in drought conditions. DSI and relative yield (RY) values for grain yield were used to describe yield stability and yield potential. There were high variations in DSI and RY values within genotypes. DSI values for grain yield ranged from 0.82 to 1.07 and the mean RY values were 0.82 for well-watered plots and 0.87 for water stressed plots. The varieties ‘Gidara-II’, ‘Sar anak-98’, ‘Balcal -2000’, ‘Alt ntoprak-98’, ‘Ayd n-93’ and ‘Harran-95’ showed high yield potential and stability (DSI<1 and RY>mean RY).
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