Polymorphism Of Three Drought-related Genes And Effectiveness Of Their Molecular Markers In Ningxia Wheat

Wheat is China’s most important food crops. Drought is one of the major limiting factors in wheat production, increase its production to global economic development has important significance. Droughts are important factors limiting with wheat production and accelerate the process of breeding drought-resistant wheat. In this study, average relative germination rate were basis, use molecular markers of three drought-related genes, Identify 117 wheat varieties(lines) average relative germination rate and clear molecular markers of three genes associated with drought of Ningxia.The main results obtained in this study are summarized below.1. Average relative germination rate of drought resistance identification showed that 117 Ningxia wheat varieties(lines) germination of seeds relative germination rate averaged 73.3%, the range of variation of 25.8 % ~ 98.2 %, there are significant differences between varieties(lines). Which identified 4 High resistance varieties(lines),accounting for 3.4 %; 35 Resistance varieties(lines), accounting for 29.9 %; 49 Medium resistance, accounting for 41.8%; 24 Sensitivity varieties(lines), accounting for 20.5 %; 5 High sensitivity, accounting for 4.2 %. In 117 Ningxia wheat varieties(lines) there are 88 Medium resistance and above varieties(lines), accounting for 75.2 % of the total, more than two-thirds; 29 Sensitivity and down varieties(lines), accounting 24.8 % of the total, less than a third, indicating that the overall wheat in Ningxia drought resistance. Mountainous and southern area of Ningxia average relative germination rate is relatively higher than the irrigated areas, Winter wheat of Ningxia average relative germination rate is relatively higher than spring wheat. Showed that average relative germination rate of seeds relative with ecological regions, but also with winter varieties related.2. Use RpDD gene locus closely linked SSR markers Xbarc56 and Xbarc117 of 117 Ningxia wheat varieties(lines) test results, showed that marker Xbarc56 in Ningchun 2 and other 76 varieties wheat varieties(lines) amplified 101 bp fragment size band, noted Xbarc56-101 allele types, average relative germination rate of 74.4 %, accounting for 64.9 %; Ningchun 7 and other 41 varieties wheat varieties(lines) amplified 117 bp fragment size band, noted Xbarc56-117 allele types, average relative germination rate of 62.3%, accounting for 35.1 %. Xbarc56-101 allele in the type and proportion of the average relative germination rate were significantly higher than Xbarc56-117 allele type; Xbarc117 in Heshangtou and other 74 varieties(lines) amplified 212 bp fragment size band, noted Xbarc117-212 allele types, average relative germination rate of 73.6 %, accounting for 63.3 %;Wuzhaolong and other 43 varieties(lines) amplified 219 bp fragment size band, noted Xbarc117-219 allele types, average relative germination rate of 64.6%, accounting 36.7 %, Xbarc117-212 allele in average relative germination rate was significantly higher than Xbarc117-219 allele types.3. Use Ta Nrx-B1 gene two dominant complementary STS marker TaNrx-B1a1 and TaNrx-B1b1 of 117 Ningxia wheat varieties(lines) test results,showed that Ningchun 1 and other 76 varieties(lines) amplify 841 bp fragment size band for TaNrx-B1 a allele types, average relative germination rate of 71.4 %, accounting for 64.9 %; Ningchun 6 and other 41 varieties(lines) amplify 845 bp fragment size band for TaNrx-B1 b allele types, average relative germination rate of 62.2 %, accounting for 35.1 %; TaNrx-B1 a allele in average relative germination rate was significantly higher than TaNrx-B1 b allelic variation types.4. Use TaFer-A1 gene co-dominant STS marker TaFerA1-intrl of 117 Ningxia wheat varieties(lines) test results,showed that Ningchun 1 and other 87 varieties(lines) amplified 167 bp fragment size band for TaFerA1-a allele types, average relative germination rate of 67.3%, accounting for 74.3%; Ningchun 7 and other 30 varieties(lines) amplified 170 bp fragment size band for TaFerA1-b allele types, average relative germination rate of 62.2%, accounting for 25.7%, TaFerA1-a allelic variation in average relative germination rate was significantly higher than TaFerA1-b allele types.5. 117 detected wheat in Ningxia, three kinds of drought-resistant genes have 8 kinds of combinations of allele types, each combination type average relative germination rate and proportion varies. Xbarc56-101 / TaNrx-B1 a / TaFer-A1 a combination type of average relative germination rate was up to 75.4%, accounting for 46.5%, and Xbarc56-117 / TaNrx-B1 a / TaFer-A1 b type combination lowest average relative germination rate was 63.4%, accounting for 17.1 %. On a single gene(locus), the average relative germination is RpDD> TaNrx-B1> TaFer-A1.Average relative germination rate results show that Ningxia overall wheat drought resistance are high, Phenotypic and molecular markers associated with the test results showed that the three drought molecular genetic markers on wheat drought resistance are closely related, molecular markers is an effective method of drought resistance identification.