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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.
Heritability and genetic gain of some morphophysiological variables of durum wheat (Triticum turgidum var. durum)
D Kahrizi, K Cheghamirza, M Kakaei, R Mohammadi, A Ebadi
African Journal of Biotechnology , 2010,
Abstract: The purpose of this work is to estimate genetic variability parameters and relationship among 11 agrophysiological traits studied on 18 experimental durum wheat and two checks under rainfed condition. The studied traits included the grain yield (YLD), plant height (PH), number of tiller per plant (NT), peduncle length (PL), flag length (FL), leaf dry weight (LDW), stem dry weight (STW), spike dry weight (SPW), spike height (SH), leaf area index (LAI), crop growth rate (CGR), relative growth rate (RGR), leaf area ratio (LAR) and net assimilation rate (NAR). Analysis of variance showed a significantly variation among genotypes for the characters PH, NT, PL, FL, LDW, STW, SPW, SH, LAR and NAR. High correlations were found among the PL, LDW, STW, SPW, LAR and NAR. Heritability estimates were high for PH, PL, LDW, STW and NAR. High genetic gains were observed for YLD, NT, PL, LDW, STW, SPW, LAR and NAR.
Evaluating Grain Quality Traits and Their Heritabilities in Durum Wheat Genotype  [cached]
M. Eslami,S.A.M. Mirmohammady Maibody,A. Arzani
Journal of Science and Technology of Agriculture and Natural Resources , 2005,
Abstract: To evaluate heritability, phenotypic and genotypic correlation coefficients, phenotypic and genotypic variances as well as relationships between some of the grain quality traits, an investigation was conducted in a randomized complete block design replicated three times in 2001, using four durum wheat genotypes PI40100, Dipper-6, Oste/Gata, Shova and their F2 and F3 progenies derived from their crosses. Grain quality characteristics including seed hardiness, protein content, SDS sedimentation volume and gluten content were evaluated. The results indicated that wet gluten content and dry gluten content had the highest coefficient of variation. Statistical analysis showed a significant difference between genotypes for all traits with the exception of SDS sedimentation volume. Dry gluten content had the highest heritability (90.4%) while SDS sedimentation volume had the lowest heritability (48.6%). Results of correlation analysis indicated that seed hardiness correlated significantly with protein content, SDS sedimentation and dry gluten content. Protein content had a positive correlation with wet and dry gluten content. Since dry gluten content showed a high correlation with protein content (quantity) and seed hardiness had a high correlation with SDS sedimentation volume, hence these two traits can be used as the selection criteria for improving quality of protein in durum wheat.
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.
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.
Remobilization of Dry Matter, Nitrogen and Phosphorus in Durum Wheat as Affected by Genotype and Environment
Silvia Pampana,Marco Mariotti,Laura Ercoli,Alessandro Masoni
Italian Journal of Agronomy , 2008, DOI: 10.4081/ija.2007.303
Abstract: Field studies were carried out to determine dry matter (DM), nitrogen (N) and phosphorus (P) assimilation until anthesis and DM, N and P remobilization during grain filling in wheat. Twentyfive durum wheat (Triticum durum L.) varieties were grown in Tuscany at Grosseto and at Arezzo. At Grosseto 76% of DM was assimilated during pre-anthesis while at Arezzo the amount was 81%. At Grosseto 44% and at Arezzo 35% of N was accumulated until anthesis, while 33% of P was stored until anthesis in both localities. Cultivar differences in DM and N remobilization were positively related to pre-anthesis dry matter and N content at anthesis (r > 0.74). Environmental contraints on carbon, N and P availability in the plant are crucial factors in determining grain yield and N and P content in grain, affecting both accumulation and remobilization. In the low rainfall site of Grosseto, most of the grain yield originated from dry matter accumulation, while in the wetter environment of Arezzo remobilization and accumulation contributed equally to grain yield. Conversely, at Grosseto grain N content relied most on remobilization and at Arezzo remobilization and accumulation contributed equally. Finally, at Grosseto and at Arezzo accumulation of P was the main source of grain P content.
Remobilization of Dry Matter, Nitrogen and Phosphorus in Durum Wheat as Affected by Genotype and Environment  [cached]
Silvia Pampana,Marco Mariotti,Laura Ercoli,Alessandro Masoni
Italian Journal of Agronomy , 2011, DOI: 10.4081/ija.2007.303
Abstract: Field studies were carried out to determine dry matter (DM), nitrogen (N) and phosphorus (P) assimilation until anthesis and DM, N and P remobilization during grain filling in wheat. Twentyfive durum wheat (Triticum durum L.) varieties were grown in Tuscany at Grosseto and at Arezzo. At Grosseto 76% of DM was assimilated during pre-anthesis while at Arezzo the amount was 81%. At Grosseto 44% and at Arezzo 35% of N was accumulated until anthesis, while 33% of P was stored until anthesis in both localities. Cultivar differences in DM and N remobilization were positively related to pre-anthesis dry matter and N content at anthesis (r > 0.74). Environmental contraints on carbon, N and P availability in the plant are crucial factors in determining grain yield and N and P content in grain, affecting both accumulation and remobilization. In the low rainfall site of Grosseto, most of the grain yield originated from dry matter accumulation, while in the wetter environment of Arezzo remobilization and accumulation contributed equally to grain yield. Conversely, at Grosseto grain N content relied most on remobilization and at Arezzo remobilization and accumulation contributed equally. Finally, at Grosseto and at Arezzo accumulation of P was the main source of grain P content.
Genotype × Environment Interaction and Stability Analysis of Seed Yield of Durum Wheat Genotypes in Dryland Conditions  [cached]
Mohtasham MOHAMMADI,Rahmatollah KARIMIZADEH,Tahmaseb HOSSEINPOUR,Hosein Ali FALAHI
Notulae Scientia Biologicae , 2012,
Abstract: The objective of this investigation was to evaluate seed yield of twenty durum wheat (Triticum turgidum spp. durum) genotypes. Evaluation of genotype × environment interaction and stability were also carried out at five diverse locations during the 2007-2009 growing seasons. Significant differences were found among the genotypes for seed yield on individual years and combined over years, in all locations. Genotype × environment interaction showed significance (p>0.001) for seed yield. According to the coefficients of linear regression and deviations from the regression model, genotypes G2, G7 and G8 proved to be the most stable while based on α and λ parameters, genotypes G7, G12 and G13 were identified the most stable. Clustering genotypes based on all stability methods and mean yield divided them into four major classes, which Class II had relatively high stability and high mean yield performance. To compare relationships among stability statistics, hierarchical clustering procedure showed that the ten stability statistics and mean yield could be categorized into three major groups, which methods of Group C indicated dynamic concept of yield stability. The genotypic stability, stability variance, superiority index and desirability index provide information for reaching definitive conclusions. Also, the best recommended genotypes, according to the present investigation, were G2 (2697.18 kg ha-1), G7 (2644.70 kg ha-1), G8 (2580.16 kg ha-1) and G10 (2637.43 kg ha-1), which had high mean yield and were the most stable genotypes based on the above mentioned stability statistics.
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.
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