我国近年来选育出一些双穗、多穗玉米杂交种,它们多比单穗种增产,如双穗型泰单75单交种,比大棵单穗型增产30—40％,在高肥水的条件下,亩产接近千斤或超过千斤;多穗玉米杂交种穗穗红220,比对照种双穗白2号增产20％。据国外报道,双穗玉米即使在干旱年份及密植条件下一般也能形成一个小穗,比单穗玉米的空秆率相对为低。这说明玉米单株果穗数的多少与产量有密切的关系。金的肯斯研究认为,玉米单株果穗数与产量有相关性,如白玉米杂交组合中相关系数为0.40±0.14,早黄玉 In recent years, China has bred a number of double-spike, multi-spike hybrid maize, which are more than single spike yield, such as double-spike Taidan 75 single cross, than single-spike yield 30-40% Under the conditions, the yield per mu was close to the kilogram or exceeded the kilogram; the ear-ear of hybrid wheat with multiple ears was 220, which was 20% more than that of Shuangsui-2. According to foreign reports, even in dry years and close planting conditions, double-ear corn can generally form a spikelet, which is relatively lower than that of single-ear corn. This shows that the number of maize plant per plant and yield are closely related. Gold’s Kins study believes that there is a correlation between the number of ears per plant and the yield of maize, as shown in the correlation coefficient of 0.40 ± 0.14 in white maize hybrids,