高密度对不同基因型夏玉米农艺特性、产量性状及耐密性的影响

为研究种植密度对不同夏玉米品种农艺性状、产量与耐密性的影响,在高密度（75000、90000株/hm²）条件下,对14个不同基因型夏玉米的农艺性状、产量构成因子以及耐密性系数等进行研究。结果表明,增密对14个不同基因型夏玉米品种生育期没有影响,株高、穗位高、茎粗、节间长度、茎粗系数、地上部干物质等农艺性状的差异达显著或极显著水平,穗位高系数、经济系数差异不显著,其中,株高平均增高1.23 cm,穗位高平均增高1.92 cm,第3节节间长度减小0.42 cm,‘NK718’、‘农大372’的地上部干物质质量增加,其余品种地上部干物质质量减小,减少幅度4.72%~23.99%,经济系数增加4.71%。75000 株/hm²条件下的产量、穗部性状与90000株/hm²密度条件相比,差异达极显著水平,在90000株/hm²密度条件下产量增加2.39%、穗粒数减少5.68%、百粒重降低1.17%。14个夏玉米品种相比,‘泽玉8911’、‘新单61’及‘豫单9953’耐密性系数值较大,适宜密植。

Effects of High Density on Agronomic Traits,Yield Components and Tolerance of Different High Density Maize Genotypes

To study the effects of planting density on the agronomic traits, yield and density tolerance of different summer maize varieties, agronomic traits, yield components and density tolerance coefficients of 14 different genotypes of summer maize were studied under high density (75000 plants/hm² and 90000 plants/hm²). The results showed that increasing planting density of the 14 different genotypes of summer maize had no effect on the growth period, but the difference of plant height, ear height, stem diameter, internode length, stem diameter coefficient, aboveground dry matter and other agronomic traits reached significant or extremely significant level. There was no significant difference of the ear height coefficient and economic coefficient of the varieties. Among them, the average plant height increased by 1.23 cm, the average ear height increased by 1.92 cm, the length of the 3^rd internode decreased by 0.42 cm. Except ‘NK718’and ‘Nongda 372’, the weight of aboveground dry matter of other varieties decreased by 4.72%-23.99%, and the economic coefficient increased by 4.71%. The yield and ear traits of 75000 plants/hm ²were significantly different from those of 90000 plants/hm². Under the density of 90000 plants/hm², the yield increased by 2.39%, the kernels per ear decreased by 5.68%, and the weight of 100-kernel decreased by 1.17%. In comparison, the variety of ‘Zeyu 8911’, ‘Xindan 61’ and ‘Yudan 9953’ have higher densification coefficient, which are suitable for high-density planting.