قرابت دو گندم پوشيينه دار با گندم هاي ديگر و وراثت صفت پوشينه

چكيده انگليسي :

Genetic Relationship Among Two Hulled Wheats with Other Wheats and Inheritance of Hulled Characteristic Fatemeh Samadi khozani f samadi 2006@yahoo com March 11 2009 Department of Agronomy and Plant Breeding Isfahan University of Technology Isfahan 84156 83111 IranDegree M Sc Language FarsiA Mirlohi Prof Supervisor mirlohi@cc iut ac irAbstract The hulled wheats are among the earliest domesticated Triticeae by humankind Hulled wheatshave thickened tough glumes and during threshing the spike will break up in to spikelets in which thegrain is surrounded by the tough glumes In the free threshing wheats the glumes are thin and easilybroken off and the chaff will separate from the grain easily A single gene the Q factor localized onlong arm of chromosome 5A is responsible for hulledness in many genotypes of wheats This type ofwheat can be found with different ploidy levels including the diploid einkorn 2n 2x tetraploidemmer 2n 4x and hexaploid spelt 2n 6x They possess many agronomic traits such as abioticstress tolerances salt drought and heat biotic stress tolerances powdery mildew rusts and fusariumhead blight higher grain protein quality and quantity and higher micronutrient concentrations Zn Fe and Mn These characteristics has made hulled wheat a useful germplasm resource and highlyvaluable in wheat breeding programs Hulled wheats are found in different regions of Iran but theirgenetic potential is not exploited owing to lack of genomic information Two hulled wheat accessions Zarne and Jonghan collected from farmers filed in two distantly located villages in the Chehar Mahal Bakhtiari province seemed to hold characteristics valuable for wheat improvement Preliminary cytogenetic studies revealed the tetraploid nature of both accessions and dismissed ourinitial presumption that they are hexaploid spelt To elucidate the genetic relationships with otherwheats we compared the two hulled accession with other 28 diploid tetraploid and hexaploid wheatgenotypes using seventeen Simple Sequence Repeats SSR primers The SSR markers designated asXGWM were obtained from a previous report mapping them on the A and B genomes of wheat These primers generated between 2 to 11 allels per locus and the average number of alleles per locuswas 4 36 The value for allelic polymorphism information content PIC ranged from 0 25 to 0 85with an average of 0 53 per locus The high value of PIC showed that a high level of polymorphismwas present for accessions classification Based on the primers representing the A 9 primers and B 8 primers genomes the results indicated that the B genome 4 07 alleles per locus was morevariable than the A genome 3 8 alleles per locus Based on the principle component analysis PCA the first second and third component PCs accounted for 19 9 6 6 and 4 8 of the total variation respectively Overall these PCs explained 31 3 of the total variation indicating that the SSR markerswere uniformly distributed over the genome The dendrogram derived from SSR data clustered twoaccessions of hulled wheat Zarne and Jonghan with two T dicoccoides wild emmer in a singleclade while T dicoccum domesticated emmer appeared in a distantly related clade The three T durum free threshing were placed in a separate cluster distant from T dicoccum These resultsshowed that Zarne and Jonghan genotypes have closer affinity to T dicoccoides than T dicoccumgenotype Separate from molecular study we attempted to determine inheritance of hulledcharacteristic using interspecific crosses In order to do this the two hulled genotypes were used aspaternal parents and were crossed to T durum Aria Shova and karkhe and T aestivum Ghods Alimited number of hybrid F1 seeds were produced possibly due to degrees of cross incompatibilities lack of ideal environmental conditions or uncontrollable experimental factors The obtained F1 hybridseeds were grown to maturity and observed for the presence or absence of the trait The seeds derivedfrom the F1 plants were all devoid of hull This

صمدي خوزاني، فاطمه

قرابت دو گندم پوشيينه دار با گندم هاي ديگر و وراثت صفت پوشينه

هيبريد , رابطه قرابتي , آغازگر SSR , نشانگرها , كاربرد ايمر