Research About Agronomic Characters And Water Use Efficiency Of10Summer Maize Varieties

Huang-huai-hai region is the biggest winter wheat-summer maize crop rotation area, alsoan important maize producing area of our country, to research the relationship betweenmaize yield and traits, and improving their WUE, will provide basis for maize varietyimprovement. Agronomic characters and WUE of main varieties in summer seeding area wereresearched in this paper, then got following conclusions:1.Difference between varieties of different WUE are mainly because the coordinationability between plant growth and ear growth.Water use efficiency is closely linked with yield, dry matter's accumulation in grainfilling stage is to some extent indict the increase of production.For example, Jiyu3hao's plant height increases fastest in Huge bellbottom period, whichhave more rainfall during the whole growth period, and when meat grain filling stage, thebiological yield per plant increases faster than plant height, meanwhile, the area of green leafare moderate, this show that this period the panicle biological yield per plant is accumulatedhigher. Medium WUE variety Denghai605's plant height is increasing fastest in grain fillingstage, biological yield per plant increase small, at the same time, the area of green leaf issmall, root number is moderate;When other varieties are stop growing in mature stage,Denghai605still available to use the precipitation to increase the production of its own.Lower WUE variety Huafeng8's plant height was increasing quickly in huge bellbottomperiod, plant height and biological yield per plant increased larger than the other two varietiesin grain filling stage, it shows that the increase of the biological yield per plant are used tosupport both plant elongation and panicle growth. Results shows, difference between varietiesof different WUE are mainly because the coordination ability between plant growth and eargrowth.2.Direct effect to yield from Leaf numbert is-0.366.Path analysis shows that, direct path coefficient of leaf number to yield is-0.366,but its'indirect effect through kernel weight is0.105, this may have related with maize's nutritionaccumulation during the mature period. kernel weight have the greatest direct influence for grain weight, the direct path coefficient is0.909, this explains that the kernel weight isdirectly determine the weight of grain。3.Summer maize's corncob length has closely content with yieldRelated analysis shows that, grain number of one row and corncob length are positivelycorrelated with grain yield, their correlation coefficient is0.824and0.709; while,length ofbald have a negative correlation with grain yield, is0.703。Root number, biological yield, earweight, grain number of one row, corncob length, corncob weight, kernel weight,100-grainweight, kernel length was positively associated with grain yield. But perimeter of corncob,kernel wide, length of bald, row number, area of green leaf, leaf number, ear height and plantheight,this several traits was negatively correlated with grain yield.4.Summer maize varieties improving should focus on leaf number and area based onselect the traits of earComprehensive analysis results indicate that breeding of water-saving and high yieldsummer maize, must focus on traits of maize ear, including grain weight of ear, grain numberper row and corncob length. In plant type, select varieties which has the suitable Area ofgreen leaf and number of leaf, is important to guaranty the yield of summer maize5. Clustering analysis for tested varieties use principal componentThe results divided the10tested varieties into five types. The first kind is have bettercomprehensive performance in all traits, including Nongle988and Liyu18, both of this twovarieties' yield are over11000kg·hm^-2, their water use efficiency also above3.05kg·m^-3;The second kind is better performance on spike character, but worse on plant type, includingJiYu3, Zhongke11and Yuanshen213, the three varieties' yield all above10000kg·hm^-2,their water use efficiency is also higher than2.8kg·m^-3. The third kind is the varietieswhich performance moderate in all characters, including Jinong1, yield of Jinong1is10929.04kg·hm^-2, and water use efficiency is3.01kg·m^-3. The fourth class is the varietieswhich performance worse in all characters, including Xundan20, Xundan18and Huafeng8,yield of these three varieties are all above9000kg·hm^-2,their water use efficiency are alsoabove2.5kg·m^-3. The fifth class is the variety which performance good on plant type, butworse on ear traits, this class only have one variety, Denghai605, yield of Denghai605ismedium level in10tested varieties, but its water use efficiency is come to2.89kg·m^-3, belongto water use efficiency good varieties.6.It is feasible to achieve water-saving ton rice field in Huanghuaihai winterwheat-Summer maize crop rotation region.Comprehensive2010²011winter wheat and summer maize two crops yield can see,under water-saving irrigation conditions, choose drought resistance wheat varieties and main popularize maize varieties, will achieve the level of ton rice field. It shows that inHuang-huai-hai region ton rice field is completely feasible.