DK743引种高产群体结构的研究

Study on High-Yield Colony Structure of Introduced Maize DK743

研究了DK74 3玉米杂交种的密度效应 ,结果表明 :(1 )经济产量 -密度方程呈渐近线型 ,经济系数 -密度方程呈指数下降型。 (2 )密度为 6 .75× 1 0 4株 /hm2 的群体经济产量最高为 1 330 0 .33kg/hm2 ,干物质积累总量为2 6 4 4 7.2 6kg/hm2 ,平均干物质生产率为 2 1 1 .6 9kg/hm2 ·d ,收获穗数 6 .75× 1 0 4穗 /hm2 ,穗粒数 5 5 9粒 ,千粒重35 2 .4 9g ,经济系数 0 .5 0 2 9。吐丝期叶面积系数最大值为 4 .6 4 97,成熟时 3.80 5 9,群体叶面积发展动态为前慢 ,中快 ,后衰缓 ,全生育期总光合势 (LAD) 4 0 8.95× 1 0 4m2 ·d/hm2 ,平均净同化率为 6 .75g/m2 ·d 。

We studied the density on DK743 . The result showed that:(1)Economic yield-density assume asymptote model , Economic coefficient-density,exponentiall decay curve. (2)At the density of 6 75×10 4 plants/hm 2,most economic yield was 13 300.33 kg/hm 2, the quanity of dry matter was 26 447.26 kg/hm 2,the average dry matter productivity was 211.69 kg/hm 2·d,67 500 spikelet and grain numbers 1 000 grain weight economic coefficient were 559 ,352.49 g,0.502 9 respectively.the development trends of conopy appareut leaf-area was slow,fast and substractive respectively in early,middle and later period of growth. and maximum leaf-area coefficient were 4.649 7 in heading period, 3.805 9 in the mature period. Total LAD and the average NAR in tota growth time were 408.95×10 4 m 2·d/hm 2 and about 6.75 g/m 2·d .It was the best yield structure.