DArT Marker-based Genetic Diversity, And Evaluation Of Main Processing Quality Parameters Of Xinjiang Spring Wheat Landraces And Historical Varieties

Germplasm resources play an important role in breeding.A large number of wheat germplasms have been preserved and accumulated in Xinjiang.Xinjiang spring wheats showed high genetic diversity in quality associated traits,tolerance to drought and cold stress,and resistance to disease and insect.It's also had strong adaptability to local climate and ecological conditions.In this study,using 90 Xinjiang spring wheat landraces and historical varieties as materials,the genetic diversity of these wheats was evaluated by DArT markers.Further,the main processing quality parameters of these wheats in Northern Xinjiang Anning canal and Southern Xinjiang Zepu during two years(2016,2017)were analyzed.The main objects of present study were:(1)to understand the genetic diversity of Xinjiang spring wheat and the variation of main processing quality parameters.(2)to screen materials with special processing quality.The main results were as follows:1.A total of 34,653 effective DArT markers were obtained,of which 19,652 were clearly located on the specific chromosomes.Among them,6,681,8,369,and 4,502 markers were distributed on the A,B,and D chromosomes,with the most distributed on 7A,2B,and 2D,and the least on 1A,4B,and 5D,respectively.Genetic diversity and cluster analysis of 89 Xinjiang spring wheats were carried out with these effective DArT markers.The genetic similarity coefficients among materials were ranged from 0.382 to 0.958 with an average of 0.583.The test materials were divided into five groups at a genetic similarity coefficient of about 0.55,including 1,1,24,2,and 61 landraces or historical varieties,respectively.In the 5 groups,the third group included 11 landraces(for example 3933)from northern Xinjiang and 13 historical varieties(Viz.Xinchun 6 et al.).The fifth group included the most landraces,like 3878 and 3879 et al.,mostly from southern Xinjiang.2.It was showed that Xinjiang spring wheats had extensive variation in protein content,Zeleny sedimentation value,wet gluten content,dry gluten content,gluten index,water absorption rate,developing time,stability time,weakening degree,and farinograph quality number.The average value in these parameters in two ecological points during two years were ranged from 16.32-18.83 %,32.28-37.98 ml,33.30-40.50 %,11.36-14.09 %,62.64-80.45,59.66-62.54 %,3.52-7.81 min,6.16-11.10 min,67.38-91.03 FU,and 65.11-120.55,respectively.The protein content,wet gluten content and dry gluten content of landraces showed that Zepu Point was higher than Anning canal Point,and the content of dry and wet gluten content in the same place in 2016 was higher than in 2017,the coefficient of variation and range of the historical varieties in most quality parameters such as protein content and sedimentation value were smaller than that of the landraces as well,suggesting that the landraces mutated more widely on these traits.The coefficient of variation of different quality parameters was quite different.The coefficient of variation of protein content and water absorption rate were less than 15 %,explaining the stability was relatively good.The developing time,stability time,weakening degree and farinograph quality number had relatively large coefficient of variation,all above 30 %,and the other parameters had a coefficient of variation between 15 – 30 %.The protein content,Zeleny sedimentation value,wet gluten content,water absorption rate and stability time of 90 Xinjiang spring wheat were analyzed by clustering,which were divided into four groups,including 15,14,58 and 3 materials respectively.Relatively speaking,the second group had the best bread quality.3.According to the quality performance of 90 Xinjiang spring wheats in two years and two points,there were seven materials with better comprehensive quality parameters,namely landrace 3972,3957,3977,3881,3893 A,4080A and 3986,were selected.Theirs protein content,sedimentation value,wet gluten content,water absorption rate and stability time all met the China strong gluten wheat national standards,accounting for 7.78 %.Meanwhile,a number of materials with good performance of single quality traits were screened,including three materials(4103,3968 and 3969)with high protein content(>20 %),four materials(4080A,3996,3994 and 3986)with high sedimentation value(> 46 ml),two materials(3933 and 4031)with low sedimentation value(<27 ml),three materials(3968,4095,and 3969)with high wet gluten content(> 44 %),four materials(Xinchun 19,Xinchun 15,3969,and 3973)with high water absorption rate(>68 %),and three materials(3977,Xinchun 8 and 4080A)with high stability time(>15 min).These genetic resources have potential value for wheat quality improvement.