不同株高玉米果穗性状对种植密度的反应

为了阐明玉米不同株高品种果穗性状对密度的反应,试验采用双因素裂区设计,主处理选先玉335、郑单958和高优1号3个不同株高品种,副处理设45 0005、3 250、61 500、69 750和78 000株/hm25个密度,调查玉米农艺性状。结果表明:密度对穗长、穗粗、秃尖度、穗行数、行粒数、穗粒重、结实率、苞叶与花丝干重、穗轴和穗柄干重均有极显著影响,其中穗长、秃尖度、行粒数、穗粒重、结实率、苞叶和花丝干重6个性状因密度处理的变化幅度3品种有显著差异,穗长、行粒数、穗粒重、结实率、苞叶和花丝干重5个性状因密度处理的变异系数呈现了高秆品种大于中秆、中秆品种大于矮秆的规律性变化。增加密度,主要通过降低行粒数使穗粒数减少,秃尖增加幅度大于穗长和穗粗的降低幅度,出籽率是玉米品种在密度影响下表现较为稳定的性状。

Responses of ear characters of corn with uneven plant height to planting density

In order to study the effect of planting density on ear characters of corn with uneven plant height,an experiment was conducted based on a split plot design with corn hydrids XY335,ZD958 and GY1 as main plot and planting density of 45000,53250,61500,69750 and 78000 plant/hm2 as subplot.The planting density significantly affected the ear length and diameter,bald tip degree,row number per ear,grain number per row,ear grain weight,seed-set percentage,bract and silk dry weight,cob and ear pedicle dry weight.There was significant difference among hybrids associated with variation of planting density for ear length,bald tip degree,grain number per row,ear grain weight,seed-set percentage,bract and silk dry weight.Variation coefficient from planting density for ear length,grain number per row,ear grain weight,seed-set percentage,bract and silk dry weight ranked as tall hybrid,medium hybrid and short hybrid.Increased planting density led to decrease in ear grain number due mainly to reduced grain number per row,and the increase of bald tip was larger than the decrease of ear length and width.Percentage of grain to ear was a stable trait that was less affected by planting density for a given hybrid.