在67 500株/hm2与82 500株/hm2两个密度水平下，对临洮县大面积种植的3个玉米品种(系)豫玉22号、先玉335及自选163的产量、株高及行粒数等耐密性评价指标参数进行了分析。结果表明，在两个密度水平下，自选163折合产量差异不显著，株高与行粒数表现出显著或极显著差异；豫玉22号与先玉335折合产量差异达极显著水平，株高与行粒数差异不显著。表明产量、株高及行粒数等指标可用于玉米材料与品种的耐密性评价。在 82 500株/hm2密度水平下，先玉335、豫玉22号折合产量分别为21 548.8、20 372.0 kg/hm2，较自选163分别增产20.82%、14.22%。可见先玉335、豫玉22号属耐密玉米品种，在玉米生产中可适当增加种植密度。

Under 67，500 /hm2 and 82500 /hm2 density levels， density tolerance evaluation parameters such as yield， plant height and row grains of Yuyu 22， Xianyu 335 and 163(breeding by author)， which cultivated in large-scale in Lintao county， were analyzed . The results showed that under the two density levels， equivalent yield of 163 was not significant difference， plant height and row grains were significant or highly significant difference； Equivalent yield of Yuyu 22 and Xianyu 335 were significant difference， plant height and row grains was not significant difference. It indicated that the yield， plant height and row grains could be used for density tolerance evaluation of corn materials and varieties . Under 82 500 /hm2 density levels， equivalent yields of Xianyu 335， Yuyu 22 were 21 548.8 and 20 372.0 kg/hm2， increased by 20.82% and 14.22%， respectively， compared with optional 163 . Therefore， Xianyu 335 and Yuyu 22 are higher density-tolerant varieties， the planting density could be increased reasonably.

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定西市科技计划资助项目“高产、优质玉米新品种选育”部分内容