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Genotype x Environment interaction for quality traits in durum wheat cultivars adapted to different environments
M Taghouti, F Gaboun, N Nsarellah, R Rhrib, M El-Haila, M Kamar, F Abbad-Andaloussi, SM Udupa
African Journal of Biotechnology , 2010,
Abstract: The quality traits of durum wheat are important for the utilization by the industries. These traits may be influenced by genotype and interaction of genotype and environment (GxE). To evaluate the effects of genotype, environment and genotype x environment interaction on quality traits such as vitreousness, SDS sedimentation test, yellow pigment index, protein content and test weight, twelve Moroccan durum wheat cultivars representing a range of agronomic adaptation were tested in five locations representing a range of environments in three growing seasons. The results indicated significant effects of genotype, environment and GxE for all the quality traits. The extent of these effects differed; for SDS sedimentation volumes, yellow pigment and test weight, the component of variation due to genotype was larger than due to the environment, indicating the greater influence of genotypes on these traits. However, for vitreousness and protein content, the effect of environment was higher than the effect due to genotypes. Thus, these traits are controlled greatly by environmental effects than genetics. The variation due to GxE was higher than that of genotype for vitreousness and test weight, indicating high GxE interaction effect and less genotypic stability for these traits. For protein content, where the environmental effect was greater than that of genotype and GxE effect, multiple environmental trials are necessary in order to determine protein content of a cultivar. For other traits, preliminary evaluations can be done in one environment and good performing ones can be selected for multiple environmental trials.
Genotype x Environment Interaction and Phenotypic Stability Analysis for Grain Yield and several Quality Traits of Durum Wheat in the South-Eastern Anatolia Region  [cached]
Hasan KILI?,Tacettin YA?BASANLAR
Notulae Botanicae Horti Agrobotanici Cluj-Napoca , 2010,
Abstract: The objectives of this study were to assess genotype x environment (GEI) interaction and to determine stability of 14 durum wheat (Triticum turgidum var. durum Desf.) cultivars for grain yield, test weight, thousand grain weight (TGW), vitreousness, protein content, ash content and SDS sedimentation volume. Cultivars tested in a randomized complete block design with four replications across 8 environments of South-Eastern Anatolia Region of Turkey, were analyzed using four parametric stability measures (bi, S2di, R2 and a). A high GEI was determined for all traits. According to the stability analysis, ‘Balcali-2000’, ‘Firat-93’ and ‘Altintoprak-98’ were the most stable for grain yield. These cultivars had high mean grain yield and were non significant regression coefficient different from unity (bi = 1.0), coefficient of determination (Ri2) as high as possible. Although some cultivars were stable for one quality trait and unstable for another, the study of genotypic stability showed that ‘Balcali-2000’ cultivar had high stability for quality characteristics and determined to be the best within the pool of the studied cultivars. Furthermore, the estimated values of broad-sense heritability (H2) were found between 30.3% and 94.3%. H2 was low for vitreousness (30.3%) and ash contents (36.0%) while found high for thousand grain weight (94.3%), SDS volume (83.0%) and protein contents (75.2%). Grain yield (62.6%) and test weight (54.6%) were as moderate.
Epistasis and genotype-by-environment interaction of grain protein content in durum wheat
Bnejdi, Fethi;Gazzah, Mohamed El;
Genetics and Molecular Biology , 2010, DOI: 10.1590/S1415-47572010000100021
Abstract: parental, f1, f2, bc1 and bc2 generations of four crosses involving four cultivars of durum wheat (triticum durum desf.) were evaluated at two sites in tunisia. a three-parameter model was found inadequate for all cases except crosses chili x cocorit 71 at site sidi thabet and inrat 69 x karim at both sites. in most cases a digenic epistatic model was sufficient to explain variation in generation means. dominance effects (h) and additive x additive epistasis (i) (when significant) were more important than additive (d) effects and other epistatic components. considering the genotype-by-environment interaction, the non-interactive model (m, d, h, e) was found adequate. additive variance was higher than environmental variance in three crosses at both sites. the estimated values of narrow-sense heritability were dependent upon the cross and the sites and were 0%-85%. the results indicate that appropriate choice of environment and selection in later generations would increase grain protein content in durum wheat.
Evaluation of Pre-harvest Sprouting Resistance in Durum Wheat Germplasm  [PDF]
Reza Tavakkol-Afshari
Asian Journal of Plant Sciences , 2006,
Abstract: Pre-harvest sprouting seriously reduces durum grain quality and is considered as an important grading criterion in all market classes of wheat (Triticum sp.). In northern Iran, untimely rain and humid conditions at harvest time cause sprouting of kernels in spike. There are few researches in the literature on pre-harvest sprouting and related traits in durum wheat (Triticum turgidum L. var. durum). A two years study (2001 and 2002) was conducted to evaluate the genetic variation of sprouting resistance and related trait in the Iranian germplasm of durum wheat accessions. In 2001, a total of 532 accessions were planted under field conditions. Unreplicated samples of 10 spikes from each genotype were evaluated for spike sprouting and falling number under laboratory conditions. Using two screening methods, the 2001 study indicated that durum accessions had a similar range in sprouting score and sprouting index to the wheat check cultivars. The sprouting score for durum accessions ranged from zero to 10. Twenty-eight of selected accessions with high level of sprouting resistance were re-evaluated in a replicated study in the second year. Sprouting score and sprouting index measured in 2002 were correlated with those of 2001. According to the results of this study, there is considerable genetic variation in sprouting resistance in durum germplasm that can be exploited by breeding programs.
Variations in Content and Extractability of Durum Wheat (Triticum turgidum L. var durum) Arabinoxylans Associated with Genetic and Environmental Factors  [PDF]
Roberto Ciccoritti,Giulia Scalfati,Alessandro Cammerata,Daniela Sgrulletta
International Journal of Molecular Sciences , 2011, DOI: 10.3390/ijms12074536
Abstract: Arabinoxylans (AX) represent the most abundant components of non-starch polysaccharides in wheat, constituting about 70% of cell wall polysaccharides. An important property of AX is their ability to form highly viscous water solutions; this peculiarity has a significant impact on the technological characteristics of wheat and determines the physiologically positive influence in consumption. Durum wheat ( Triticum turgidum L. var durum), the raw material for pasta production, is one of the most important crops in Italy. As part of a large project aimed at improving durum wheat quality, the characterization of the nutritional and technological aspects of whole grains was considered. Particular attention was addressed to identify the best suited genotypes for the production of innovative types of pasta with enhanced functional and organoleptic properties. The objective of the present study was to investigate the genetic variability of AX by examining a group of durum wheat genotypes collected at two localities in Italy for two consecutive years. The environmental influence on AX content and extractability was also evaluated. Variability in the AX fraction contents was observed; the results indicated that AX fractions of durum wheat grain can be affected by the genotype and environment characteristics and the different contribution of genotype and environment to total variation was evidenced. The genotype × environment (G × E) interaction was significant for all examined traits, the variations due to G × E being lower than that of genotype or environment. The data and the statistical analysis allowed identification of the Italian durum wheat varieties that were consistently higher in total arabinoxilans; in addition, principal component analysis biplots illustrated that for arabinoxylan fractions some varieties responded differently in various environment climatic conditions.
Stability Analysis for Grain Yield and its Components of Some Durum Wheat Genotypes (Triticum durum L.) Under Different Environments  [PDF]
Mohamed S. Hassan,G.I.A. Mohamed,R.A.R. El-Said
Asian Journal of Crop Science , 2013,
Abstract: Evaluation of wheat genotypes under different environments is essential for testing stability of their performance and range of adaptations. Where, development of any crop genotypes with adaptation to changes is one of most important goal of breeding program. This study examined fifteen durum wheat accessions over different eight environments; two planting dates: Nov. 30th (favorable) and Dec. 30th (unfavorable) at two locations: Assiut and Qena during two seasons (2010/2011 and 2011/2012). The experiment was grown in a randomized complete blocks design with three replications in each location. The objective of this investigation was to study the stability parameters of the fifteen durum wheat genotypes under different environments. The combined analysis of variance for environment (E), genotype (G) and (GxE) interaction was highly significant for all studied traits, suggesting differential responses of the genotypes and the need to stability analysis. The stability parameters are useful in characterizing genotypes by showing their relative performance in various environments. Results revealed that highly yielding genotypes can also be stable. The genotype No. 12 had desired performance (grain weight/spike) compared to the grand mean, regression coefficient (bi) did not differ significantly from unity and least deviation from regression (S2d), indicating the role of linear portion of GxE interaction in the performance of this genotype. The value of regression coefficient (bi) of genotypes No. 12 for No. of grains/spike, No. 8 and 13 for grain weight/spike, No. 1, 2, 5, 8, 9, 14 and 15 for grain yield/plant were less than one (bi<1), indicating that these genotypes were considered specially adopted to unfavorable environments. Meanwhile, the value of regression coefficient of genotypes No. 9 for plant height, No. 13 for No. of grains/spike, No. 3,12 and 14 for grain weight/spike and No. 10 for grain yield/plant had bi values more than unity (bi>1) and could be adapted to optimum environment.
Estimates of Genotype x Environment Interactions and Heritability of Black Point in Durum Wheat  [cached]
Hasan KILI?,Abuzer SA?IR,Yunus BAYRAM
Notulae Scientia Biologicae , 2009,
Abstract: Experiments were carried out in four different locations with 14 durum wheat genotypes in two successful seasons of 1999- 2000 and 2000-2001. Black point disease of genotypes was evaluated by interactions of genotypes and environment as well as heritability (h2). It was found that black point disease affected differently in different locations and growing seasons. This indicates that the genotypes have different adaptation ability for traits studied in different locations. Heritability rate that variance analyzes accepted means squares calculated was found as phenotypic variance rate of genotypic variance was found as 49%. Variance of genotype x location x year was bigger than other variance components. Genotype x year variance was bigger than genotype x location variance too. The heritability of black point disease was founded moderate. In addition to one of factors on the black point disease genotype also environment x genotype interactions were found effective. According to evaluation of black point disease, the highest value was obtained from Sorgül (2.7%), Dicle-74 (2.56%) and Gidara-II (2.32%) varieties; the least value was obtained from Balcal -2000 variety (0.64%). Alternaria spp., Phoma sp., Fusarium spp., Helminthosporium spp., and Stemphylium spp., fungi were isolated from the grain affected by black point diseases.
Response of Different Durum Wheat (Triticum turgidum Var. Durum) Varieties to Added Nitrogen Fertilizer
Miesho Belay
Open Access Library Journal (OALib Journal) , 2014, DOI: 10.4236/oalib.1100873
Abstract: Twelve durum wheat genotypes were evaluated for their grain yield and related traits using two rates of nitrogen fertilizer application (69 kg N ha1 and 115 kg N ha1) in a randomized complete block design with three replications. The experiment was done on Vertisol at Adet Agricultural Research Center in the main cropping season 2009. All agronomic traits respond positively to applied nitrogen rates. The highest grain yield (33.8 Qt·ha1) was reported from Asassa variety. Grain yield increased by 8.8 Qt·ha1 with the increase of nitrogen rates by 46 kg N ha1. Studied traits, except days to heading, grain filling period and biomass production efficiency, others did not respond to the genotype by nitrogen interaction effect. Grain yield was positively correlated with plant height (r = 0.53), total plant biomass (r = 0.81).
SELECTION CRITERIA FOR IMPROVED GRAIN YIELD IN DURUM WHEAT
F. Kashta,a. Canko,P. Harizaj,N. Vata
Albanian Journal of Agricultural Sciences , 2011,
Abstract: An experiment was conducted during 2007-2008 period, with the objective of estimating the associations between yield and yield-related traits and to identify direct effects of characters for durum wheat grain yield improvement. The experimental material consisted of 20 durum wheat genotypes, which are randomly taken from the germoplasm collection. Significant genotypic differences (P<0.01) were observed for all the traits studied, indicating considerable amount of variation among genotypes for each character. 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 other hand, grain yield had strong negative correlation (p< 0.01) with days to heading, suggesting the usefulness of selecting early heading genotypes with long grain filling period in improving grain yield. The remaining traits recorded moderate to low phenotypic and genotypic estimates. The maximum positive direct effect on grain yield was exerted by biological yield (0.99) followed by days to maturity (0.89) and harvest index (0.73). While, maximum negative direct effects were exerted by days to heading (-0.81) and grain filling period (-0.68). 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.
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.
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