不同基因型玉米耐密植抗倒性分析及其鉴定指标的筛选

Lodging Resistance and Determination of Resistance Evaluation Indicators in Different Maize Genotypes under Higher Population Density Selection Pressures

以东北平原主栽的15份玉米品种为材料,采用田间试验的方法,设置4个种植密度,以7.5万株/hm^2作为对照处理,在灌浆期对玉米的株高、穗位高,茎秆基部第3节茎粗、节间长、穿刺强度、抗折力、干物质积累、鲜重、可溶性糖含量、全钾含量进行测定,根据各项指标的抗倒伏系数,通过主成分分析、隶属函数分析和聚类分析等方法对不同玉米品种灌浆期的密植抗倒性进行综合评价。结果表明,玉米10个单项指标转换成为可以鉴定玉米密植抗倒伏能力的4个相互独立的综合指标,通过聚类分析将15份玉米品种灌浆期的抗倒性划分为3类,其中,先正达408等3份玉米品种表现为高度抗倒,先玉027等8份玉米品种表现为中度抗倒,农华101等4份玉米品种表现为不抗倒。

Fifteen main varieties of maize planted in the Northeast Plain were treated under four different planting density conditions in a field experiment, and 75 000 plant/ha planting was used as control. In the filling stage of maize plant height, ear height, basal stem section third, stem diameter, internode length, puncture strength, flexural strength, dry matter accumulation, fresh weight, soluble sugar content and total potassium content were investigated at the mature period. Lodging-resistance coefficient（LRC） of all indexes was used to comprehensively evaluate the lodg- ing-resistance by principal component analysis, membership function method and hierarchical cluster analysis. The results showed that 10 single morphological indexes for maize of different genotypes under lodging-resistance stress could be recombined into four separate comprehensive indexes. On the base of comparing the lodging-resistance toler- ance comprehensive evaluation value（value D） of different maize varieties, which was calculated from the subordinate function analysis, fifteen maize varieties were divided into three groups using cluster analysis, among which three vari- eties such as Syngenta408 had higher lodging-resistance, eight varieties including Xianyu027 showed medium to-wards lodging-resistance stress, while four varieties including Nonghua 101 were not lodging-resistance.