شناسايي نشانگرهاي مولكولي ريز ماهواره مرتبط با صفات تحمل به خشكي در گندم دوروم

چكيده انگليسي :

AbstractThe effect of drought stress on some morpho physiological traits and to identify themicrosatellite SSR molecular markers related to these traits were studied in apopulation of 151 F3 and F4 lines derived from a cross between the drought tolerance Oste Gata and susceptible Massara 1 durum wheat genotypes Field trails wereconducted as randomized complete block designs either under stress and non stressmoisture conditions at reproductive growth stage in 2003 and 2004 The families wereevaluated for the following traits plant height peduncle length spike length awnlength length and width of flag leaf heading date days to pollination days to maturity grain weight per spike grain number per spike spike number per m2 1000 grainweight spike weight grain yield biomass harvest index spike harvest index testweight grain protein content relative water content RWC leaf water content LWC and excised leaf water retention ELWR The means of traits relating to reproductivegrowth stage such as yield yield components harvest index days to maturity RWCand LWC were higher under non stress condition than strss condition The results ofphenotypic evaluation revealed significant differences among families especially fortraits related to reproductive developmental stage The multivariate analysis showeddifferent mechanisms for drought tolerance viz early heading with shorter vegetativegrowth period stem reserve mobilization in tall plants increasing grain filling periodand physiological traits relating to reduction of water use Analysis of variance ANOVA and combined ANOVA revealed significant genotypic variation for all traitsand the presence of genotype environment interaction for most of the traits Theestimation of genotypic and phenotypic correlation indicated significant relationshipbetween grain yield and plant height peduncle length yield components andphysiological traits under two environmental conditions Identification of the associatedSSR markers and QTLs with the studied traits were performed based on single markeranalysis and composite interval mapping CIM using 23 SSR markers in the mappingpopulation The results of stepwise regression were similar to CIM in some conditions Xbarc45 2B and Xbarc124 2B markers significantly associated with plant height underboth stress and non stress conditions Associated markers with traits evaluated underdrought conditions were Xcfd22 7B for 1000 grain weight and spike length Xbarc101 3B for peduncle length Xgwm148 2B for length of flag leaf and harvest index andXwmc166 7B for grain yield A strong QTL controlling 49 37 and 31 of phenotypicvariations of plant height peduncle and spike length was detected near Xbarc124 2B intwo environments respectively Some QTLs recognized for peduncle length onchromosomes 6A and 3B and for spike length on chromosomes 1B 3B and 5B Twostrong QTLs for length of flag leaf were detected near Xgwm11 1B and Xgwm299 3Bwhich explained 24 and 18 of phenotypic variation under non stress conditions respectively The QTL of width of flag leaf was detected near Xcfd22 7B underenvironment conditions For awn length only one main QTL was detected nearXbarc124 2B explaining 13 of its phenotypic variation Some SSR markers wererelated to heading date located on chromosomes 2B 7B and 4B days to pollination onchromosomes 7A and 3B and days to maturity on chromosome 6A The resultsrevealed that about 20 of phenotypic variation of biomass could be explained byXbarc45 2B marker Similarly the related markers Xcfd22 7B and Xcfa2114 6A forharvest index and 1000 kernel weight markers Xgwm181 Xwmc405 and Xgwm148 forspike harvest index and marker Xwmc166 for grain weight per spike were identified The QTLs and markers for the following traits were not identified grain yield grainnumber per spike spike number per m2 spike weight test weight and grain proteincontent Some minor QTLs were identified for RWC LWC and ELWR onchromosomes 1B 2B 3B 4B and 6B It is concluded that important markers and QTLscontr

گل آبادي، مريم

شناسايي نشانگرهاي مولكولي ريز ماهواره مرتبط با صفات تحمل به خشكي در گندم دوروم

تاكسونوميكي گندم , واكنش ژنوتيپي﴿PA) , نقشه هاي لينكاژي , مكان يابي QTL