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In recent years, China's agricultural challenges facing very severe reduction in arable land remains the case, you must implement the grain yield increase 30% to 40% in order to meet the needs of the future population. As China's second largest wheat crop, to achieve its yield substantial increase for China's agricultural development is crucial. To achieve further substantial increase in wheat yields purpose, we must dig Wheat Germplasm good agronomic traits, and continuously integrated traits superior breeding new varieties. For Jiangsu Province agronomic traits in wheat evolution, there are also a number of studies related scholars, some focus on the Yangtze River, and some focus on the Great Plains, on the basis of the previous research on wheat varieties in Jiangsu Province Agronomic changes conduct a comprehensive study law. This study of the production over the years to promote cultivation of varieties for statistical analysis, combined with field survey data, the consolidated number of related literature from plant type, yield traits, nutritional quality traits and agronomic traits on ecological types elaborate master wheat varieties in Jiangsu Province Resource distribution and characteristics of the replacement process, a clear Wheat Germplasm Resources in Jiangsu Province agronomic traits plant height, grain weight, protein content, spring and winter and maturity evolution, while differences in the regional distribution of agronomic traits analyzed, expectations for the next breed Wheat production improvement and provide a theoretical basis and reference. The main conclusions of this thesis are: 1, since the founding, with the scientific and technological development, Jiangsu Province Wheat Varieties experienced 6-7 times change, the application number of species grow slowly in the 1960s and 1970s, after 80 years of relatively significant growth, to the 1990s has leveled off, keep the number of varieties of resources between 35-40, chronology and inter-regional distribution of significant differences. Jiangsu Province, the gradual shift towards semi-dwarf varieties planted varieties, grain weight was 35.1 ~ 40g varieties, protein content of 11.01 - 14% of the species, lysine content of 0.30 to 0.39% of the species, weak winter varieties, cooked varieties , which accounted for the proportion of total resources varieties were 50.32%, 48.72%, 48.40%, 37.17%, 29.81%. 2, with the replacement varieties, agronomic traits also will be changed. The results showed that wheat varieties in Jiangsu Province Agronomic changes trends are: (1) Plant type: height decreased significantly reduced plant height of 56 years 24.48%, with an average annual decline of 0.45%, the difference between varieties tend to shrink; dwarf and semi-dwarf varieties substantial increase in the proportion of, respectively, from 6.7% in 1950 and 13.3% to the current 27.2% and 70.2% in the stalk, medium and tall varieties of tall proportion decreased gradually generations. (2) Yield: yield the most significant changes, 56 years production increased by 516.21%, with an average annual increase of 9.56%; grain weight increased significantly in 56 years an increase of 40.24 percent, an average annual increase of 0.72%, breed differences tend to shrink; grain weight In 40.1 ~ 45g proportion between species increased significantly, from 50 years of 6.67%, increased to 55.95% today. Path analysis showed that the province's total wheat production to improve the process, the role of yield accounted for 96.2%. Effect on yields and grain weight accounted for 93.8%. (3) Nutritional Quality Traits: protein content, lysine content was significantly increased in 56 years, respectively, an increase of 27.47%, 16.57%, the difference between varieties tend to shrink; protein content of 14.01% to 17% the proportion of the species increased significantly, From the 1950s to 6.67%, increased to 47.62% today; lysine content of 0.40% to 0.49% of the varieties proportion also increased significantly, from 50 years of 8.89%, increased to 39.29% today. (4) ecological types: spring resistance, bias spring and weak winter varieties Sui's a significant increase in winter varieties significantly reduced; in early maturing varieties with the years a significant increase in early, middle and late, late-maturing varieties decreased significantly. Dynamic analysis shows that the degree of change in the study area of ??spring, winter and weak in the early, mid-maturing varieties better adapted to farming systems and ecological conditions, an increasing number of species, the degree of change is increasing, continue to promote the benefits of having Potential ecological variety. Seen the evolution of the agronomic traits and improved varieties of wheat in Jiangsu Province and is closely related to the progress of the replacement. Currently, the plant height and grain weight average of 83.24cm and 42g, yield potential is still very visible enormous. More varieties, quality differences, the overall quality has yet to be improved, the development of appropriate zoning wheat quality imminent. Earliness and yield needs further coordination. 3, regional differences are significant agronomic traits. Biggest grain weight variation coefficient of variation was 1.89; followed by lysine, its coefficient of variation was 1.59; again for the height, coefficient of variation 1.49; finally, protein content, and the variation coefficient of 1.39. This is because regional differences in ecological conditions and planting varieties produced. Ecotype, the winter, the biggest difference in the late region. Currently, Huaibei wheat region and plant height and grain weight 83.7cm 42.6g, Huai Nan Mai district was 86cm and 41g, has considerable potential to increase yield, yield potential of greater than Huaibei District Huai Nan Mai Mai area. Variable quality, targeted construction suitable for high-quality wheat production base is necessary.
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