不同基因型玉米自交系耐密性评价与筛选

Evaluation and screening of density tolerance of inbred corn lines with different genotypes

【目的】在不同种植密度下,通过对不同基因型玉米自交系材料农艺性状及产量的分析,筛选出耐密材料及耐密性评价指标,以期为选育耐密高产玉米材料提供帮助。【方法】以68份不同基因型玉米自交系为材料,设置6.75和12.75万株/hm^(2)2个种植密度,研究密度对农艺性状及产量性状的影响。【结果】利用株高、穗位高、茎粗、叶夹角、雄穗分枝数等18个表型指标,通过模糊隶属函数法对68份材料进行耐密性综合性评价,筛选出强耐密性材料2份,中等耐密材料19份,耐密性较弱的材料46份,不耐密材料1份。通过主成分分析及逐步回归分析表明,单株产量、弯曲性能等5个指标与玉米的耐密性显著相关。【结论】筛选出强耐密材料2份,分别为GAU630、GAU810;不耐密材料1份,为GAU669。综合主成分分析与逐步回归分析结果表明,单株产量、弯曲性能、株高、穗轴重和叶夹角这5个指标可作为玉米耐密性的评价指标。

【Objective】Under different planting densities,through the analysis of agronomic characteristics and yields of different genotypes of maize inbred line materials,the density-tolerant materials and evaluation indexes of density-tolerance were screened to provide help for breeding of density-tolerant and highyield maize materials.【Method】Using 68 inbred maize lines of different genotypes as material,two planting densities of 67500 and 127500 plants/hm^(2) were established to study the effect of density on agronomic and yield traits.【Result】Using 18 phenotypic indicators such as plant height,ear height,stem diameter,leaf angle,and number of tassel branches,the density tolerance of 68 materials was comprehensively evaluated by the fuzzy membership function method.2 parts of strong density material,19 parts of medium-density material,46 parts of weak-density material,and 1 part of non-density material were screened out.Then,principal component analysis and stepwise regression analysis showed that five indicators,such as yield per plant,bending performance,plant height,cob weight,and leaf angle were significantly correlated with the density tolerance of corn.【Conclusion】2 strong density materials were screened,namely GAU630 and GAU810,and 1 non-density material was GAU669.The results of comprehensive principal component analysis and stepwise regression analysis showed that five indexes of yield per plant,bending performance,plant height,cob weight,and leaf angle could be used as evaluation indexes of maize density tolerance.