基于主成分和隶属函数分析的高粱品种耐深播性综合评价

采用盆栽试验,分别设置1、3、5、7 cm播深,对34个高粱品种在不同播深下的出苗率、幼苗形态和幼苗干物质量进行分析,筛选耐深播性鉴定指标,综合评价高粱品种的耐深播性。研究结果表明,随着播种深度的加大,出苗率、苗长、根长、根数和苗重均呈下降趋势,3、5、7 cm与1 cm播深上述指标测定值的比值分别为0.84～0.60、0.96～0.75、0.83～0.53、0.88～0.64和0.95～0.85;中胚轴长、根重和根冠比呈上升趋势,3、5、7 cm与1 cm播深上述指标测定值的比值为1.52～3.30、1.10～1.25和1.17～1.50;胚芽鞘长在播深间差异不显著。主成分分析结果表明,前4个主成分的累积方差贡献率为77.647%,相对根冠比、相对根长、相对中胚轴长和相对出苗率载荷量最大,将其作为高粱耐深播性筛选的主要指标并计算隶属函数值。根据隶属函数值对高粱品种进行聚类分析,结果显示,34个高粱品种可聚为3类,晋粱白2号等11个品种为耐深播品种,红青壳等14个品种为中等耐深播品种,吉品609等9个品种为深播敏感品种。品种间耐深播性差异明显,杂交种较常规种耐深播性强。

Comprehensive evaluation of deep\|sowing tolerance of 34 sorghum cultivars by principal component analysis and subordinate function method

In order to evaluate the deep\|sowing tolerance of sorghum cultivars and screen related identification index, we measured the emergence rate, seedling morphology, and dry weight of 34 sorghum cultivars with different sowing depths of 1, 3, 5, and 7 cm by a pot experiment. The results showed that with the increase in sowing depth, the emergence rate, seedling length, root length, root number, and seedling dry weight decreased with the relative value ranging between 0.84~0.60, 0.96~0.75, 0.83~0.53, 0.88~0.64, and 0.95~0.85, respectively. Mesocotyl length, root dry weight, and root\|shoot ratio increased by the relative value ranges of 1.52~3.30, 1.10~1.25, and 1.17~1.50, respectively, while the coleoptiles length had no significant difference among sowing depths. Principal component analysis (PCA) showed that the cumulative contribution rate of the first 4 principal components was 77.647%, and the relative root\|shoot ration, relative root length, relative mesocotyl length, and emergence rate had the maximum weight in values. These 4 traits above were used as the main indices for evaluating deep\|sowing tolerance and to calculate subordinate function values. According to the cluster analysis of sorghum varieties based on the subordinate function values, 3 groups of deep\|sowing tolerance of 34 sorghum cultivars were detected: 11 cultivars including Jinliangbai 2 were deep\|sowing tolerant, 14 cultivars including Hongqingke were medium deep\|sowing tolerant, and 9 cultivars including Jipin 609 were deep\|sowing sensitive. In conclusion, the difference of deep\|sowing tolerance among sorghum cultivars was distinct, and the tolerance of hybrids was higher than that of conventional cultivars.