春玉米不同产量群体叶面积指数动态特征与生态因子资源量的分配特点

利用吉林桦甸连续3年的田间试验结果，结合气象观测资料，对春玉米群体叶面积指数动态特征及不同产量水平下的生态因子资源量的分配特点进行了研究.结果表明：以相对生长天数、相对有效积温、相对日照时数和相对降雨量为自变量的相对叶面积指数动态模型均符合有理方程：y=（a+bx）/（1+cx+dx²）；产量（y）与吐丝前后生长天数比值（x₁）、吐丝前后有效积温比值（x₂）、吐丝前后降雨量比值（x₃）以及吐丝前后日照时数比值（x₄）的回归方程为y=5465.19+17810.64x₁-23236.14x₂+4093.41x₃+6287.37x₄(R²=0.8187，P<0.01)，各生态因子对产量的影响按照偏回归系数绝对值排序为x₁>x₂>x₃>x₄；超高产（15499.86 kg·hm^-2）生态因子资源量在吐丝前与吐丝后的比值分别为：生长天数1.43、有效积温1.41、降雨量1.44、日照时数1.40.在东北地区，适期早播，在延长总生长天数的前提下适当增加吐丝前的生长天数、降雨量以及日照时数均能提高产量，当生长天数、有效积温、降雨量以及日照时数在吐丝前与吐丝后的分配比值均约为1.4时，可获得高产、超高产.

Dynamic characteristics of leaf area index and allocation characters of ecological resources for different yielding spring maize populations.

By using 3-year field experimental results and related meteorological observation data, the dynamic characteristics of leaf area index (LAI) and the allocation characters of ecological resources for different yielding spring maiz e (Zea Mays L.) population in Huadian of Jilin Province were studied. The resul ts showed that the dynamic characteristics of relative LAI, with the relative gr owth days of test population, relative effective accumulated temperature, relat ive sunshine hours and relative rainfall as independent variables, fitted r ational formula y=(a+bx)/(1+cx+dx2), and the regression equation of maize yiel d with the ratios of growth days before and after silking (x1), effective accu mulated temperature before and after silking (x2), rainfall before and after s ilking (x3), and sunshine hours before and after silking (x4) was y=546519 +1781064x1-2323614x2+409341x3+628737x4 (R2=08187，P<001) , with the effects of these ecological factors on yield being in the sequence of x1>x2>x3>x4 according to the absolute values of partial regression coef ficients. In super high yielding (1549986 kg·hm-2) spring maize populat ion, the allocation ratios of x1, x2, x3, and x4 were 143, 141, 14 4, and 140, respectively. Therefore, in Northeast China, appropriate early sow ing of spring maize to prolong its growth days with more rainfall and sunshine h ours before silking could attain high yielding, and high or super high yield cou ld be achieved when the allocation ratios of x1, x2, x3, and x4 were all about 14.