The Agronomic Trait Identification And Molecular Marker Detection Of Wheat Germplasm From CIMMYT

The wheat germplasm resources bred by CIMMYT played an vital role in wheat breeding and producing programs in C hina, which could also enhance the genetic diversity of domestic wheat materials. The major agronomic characters of 480 common wheat germplasm lines which were introduced from CIMMYT were identified in this study. The partial reduced height genes, powdery mildew resistance genes and rust resistance genes in 885 CIMMYT materials had been investigated by molecular markers detection. The results listed as follows:The identification of the agronomic traits of 480 CIMMYT wheat germplasm lines which were introduced in 2013 indicated that they displayed abundant variation in phenotypic characteristics. The diversity index was ranging from 2.88 to 3.06. The plant height, ear length, ear number per plant, spikelet number per panicle, kernels per spike, 1 000-grain weight and weight of kernels per plant were 94.1cm, 11.9cm, 8.6, 19.1, 62.2, 41.4g and 16.3g respectively. The average grain crude protein content, wet gluten content, sedimentation value, dough stable time, dough deve lopment time and bulk density were 14.25%, 31.37%, 43.20 m L, 5.76 min, 4.1 min and 834.32 g/L respectively. The data showed that the germplasm lines had elastic stem, longer ear, quite larger ear number and spikelet number, higher weight of kernels per pla nt whereas they were generally higher. All the lines also had adult-plant resistance to powdery mildew and rust disease. These materials suggested that they had important usage value in domestic wheat resistance breeding programs and development of quality traits.885 wheat germplasm lines from CIMMYT had been detected by molecular marker detection in order to investigate the distribution of Rht-B1 b, Rht-D1 b, Rht5, Rht8, Rht12 and the frequency of the first four genes were 63.39%, 29.04%, 10.06%, 48.47% respectively; Rht12 could not be detected. Among these materials, 23 lines contained 4 dwarfing genes with the distribution frequency of 2.60% of the total; 134 lines contained 3 target genes with 15.14%; 392 lines contained 2 tested genes with 44.29%; 324 lines contained only 1 dwarfing gene with 36.61%; 32 lines could not detected any genes with 3.62%.The 885 CIMMYT wheat materials had been also investigated the resistance genes to the major wheat diseases. The distribution frequency of lines which contained Pm2, Pm4 b, Pm21 and Pm23 was 1.81%, 60.00%, 42.15% and 31.07% respectively. Only 1 lines contained 4 powdery mildew resistance genes with 0.20% of the total; 32 lines had 3 resistance genes with 3.62%; 220 lines had 2 tested genes with 24.86%. As for the rust resistance genes, the distribution frequency of Yr10, Yr15, Yr26, Lr9, Lr19 and Lr26 were40.00%, 4.18%, 67.80%, 2.37%, 7.23%and 0 respectively. 9 lines had 3 rust resistance genes with 1.02% of the total; 211 lines contained 2 target genes with 23.84%.