| To increase yield is the main goal in wheat breeding. With the development of wheat production, the yield index of wheat cultivars approach quite high level so that it is difficult to further enhance it, but various studies show that wheat still has potential to increase yield. Especially, the level of wheat yield breeding will be up-graded and wheat varieties also contribute to increase yield with the development of genetics, physiology, method and technology of breeding.In the view of serious problem of wheat growing and the ecology condition in Sichuan Basin, there are views to grow " ear number-ear weight coordination-type" and "excelled large spike with small leaf type" cultivars which were put up by Pro. Ren Zhenglong before ten years who hope to grow varieties enhancing ecological ear capacity with the ear weight unaltered in order to increase yield per unit area, which is called "Coordination-Type" cultivars. The Coordination-Type Wheat new cultivars, Chuan-nongl2 and Chuan-nongl 7 which have been passed identification in Sichuan Province and Chuan-nongl8 which will be identified in September of 2003 and have been protected by country new cultivars protect law, have been released by our group. All of them derived from hybrids between translocation lines created by chromosome engineering. Practices show that they own various good traits, such as the high tiller appearance rate, the high tiller survival rate and the high ear number per unit area besides high yield, stable yield, resistance to lodge and disease. Moreover, many of them own itself excellent trait. For example, the quality of Chuan-nong17 is very good so it is cultured and treated as bread wheat, and the early ripe stage of Chuan-non18 make it adapt to multi-ripe mechanism growth, while the ripe stage of Chuan-nong12 is moderate and its qualities is favorable to make noodle.The purpose of this study is to research the yield potential, its components, the trait of tiller appearance and survival and the plant mode with high production and high benefit. The results were shown as following:1 The Coordination-Type new cultivars yield is up to 7333.5 Kg/hm2 which increases with 6.1% versus the control cultivars Chuan-mai28. If better plant measures and condition are added, they possibly exceed the highest record 7597.5Kg/hm2 created by wheat cultivars MY11 in 1982. It is self-evident that the yield potential of coordination-type new cultivars is so high that they are the high level in all delivered cultivars.2 Yield components of the Coordination-Type produce large change. The spike number per unit area of various cultivars is 300-375 *104/hm2 in Sichuan Basin. In contrast, the soike number of the Coordination-Type new cultivars is dominant higher than control cultivars Chuan-mai28 up to 627.0* 104/hm2, which increased with 25.9 percent of the most value 498.0*104/hm2 of Chuan-mai28. It is obvious that more ear number is the main factor in increasing the yield potential of Coordination-Type cultivars, which is difference from all else wheat cultivars.3 The study demonstrated that effective ear number result from high tiller appearance rate and higher tiller survival rate. In this study, when the plant density is same, there areonly nuance of tiller appearance rate and the maximum tiller number between the Coordination-Type cultivars and Chuan-mai28, but the differences in the tiller survival rate and the spike number per unit area between them are dominant, which show that Coordination-Type cultivars have higher tiller survival rate than control cultivars (Chuan-mai28). Especially, in the low density the tiller number of single plant of the Coordination-Type cultivars is up to 11.2 and all of them became ear. So the tiller survival rate is 100 percent. While those of Chuan-mai28 is 11.0,9.0 and 75 percent.4 There is no clear difference among spikes in the same plant. The ears of single plant is up to 12, with the plant density 25* 104/hm2. Their ear height and kernel weight do not take dominant distinction though there are s...
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