Preliminary Analysis of Maize Varieties Experiments in Liaoning Province in Recent Years

The maize varieties experiments in Liaoning province in 2005 were analyzed.The conclusions showed that maize yield would be improved by taking full advantage of natural conditions since the growth period of maize variety was shortening.Maize yield was improving with the density increases,but the increasing space was limited of tested varieties.The appropriate density for medium-late maturity varieties within test was 60 000 plants/ha while late maturity varieties 52 500 plants/ha.Overall quality of tested varieties showed the lack of superior breeding materials basis.More resistance and yield stability were the basis of varieties for large-scale extension.The foundations for cultivate superior varieties as follows: To improve breeding objective,the utilization of solar energy should be improved and the number of effective panicles per unit area increased;By enlarged and improved germplasm,and increased the density pressure on the breeding base material could strengthen the accumulation of materials which maturity were relatively short and resistance to high density;Improve the awareness of resistance of varieties and yield stability.