鲜食型糯玉米新品种主要农艺性状的相关和主成分分析

陈冰洁+吕莹莹+张恩盈+张保望

摘要：为给鲜食型糯玉米新品种的综合评价和选育提供一定理论参考，以5个优良鲜食型糯玉米品种为试材，对其株高、穗位、穗重、穗粗、轴粗、穗长、秃尖长、穗行数、行粒数、百粒重、鲜穗产量、雄穗长、雄穗分枝13个性状进行相关和主成分分析。结果表明：玉米鲜穗产量与穗重、百粒重、穗粗、行粒数、穗长等性状有极显著正相关关系。对鲜食型糯玉米13个农艺性状进行主成分分析，显示前三个主成分，即鲜穗产量因子、雄穗因子和秃尖长因子，其累计贡献率达87.2767%，可以基本代表13个性状所代表的遗传信息。第一主成分是优良玉米品种选择和评判的主要指标，各性状应具备：果穗大，穗粗且轴细，即籽粒要深，穗粒数要多，百粒重要高，株高宜较高等。从第二主成分来看，鲜食玉米品种植株的雄穗最好较长，分枝不宜太多，在保证玉米雌穗对雄穗花粉量需求的同时，尽量选择雄穗分枝少的品种。从第三主成分来看，秃尖长影响了鲜食玉米的商品品质，在品种评价和选育时，应将秃尖长度控制在最低标准。

关键词：糯玉米；鲜穗产量；农艺性状；主成分分析；相关分析

中图分类号：S513.01 文献标识号：A 文章编号：1001-4942（2017）07-0016-05

Abstract In order to provide some theoretical references for comprehensive assessment and breeding of new fresh waxy corn varieties， taking 5 excellent fresh waxy corn varieties as materials， the correlation and principal component analysis of 13 traits， plant height， ear height， ear weight， ear diameter， axis diameter， ear length， bald tip length， ear rows， kernels per row， 100-kernel weight， fresh ear yield， male spike length， tassel branch number， were conducted. The results showed that there was very significant positive correlation of fresh ear yield with ear weight， 100-kernel weight， ear diameter， kernels per row and ear length. The principal component analysis showed that the accumulative contribution rates of the first 3 principal components， fresh ear yield factor， male spike factor and bald tip length factor， reached to 87.2767%， which could generally represent the genetic characteristics of 13 characters. The first principal component was the main index of selecting and judging the excellent fresh waxy corn varieties， which had the characteristics of bigger ear， larger ear diameter and smaller axis diameter. That was to say， the kernel should be deeper， the kernel number per ear should not be too much， the 100-kernel weight and plant height should be higher. The second principal component showed that the male spike should be longer， the branch number was not too much， the male spike branch number should be as low as possible while the male spike could provide enough pollen for female spike. The third principal component showed that the bald tip length could affect the commercial quality of fresh waxy corn， so the bald tip length should be controlled within the minimum standard in the process of variety assessment and breeding.

Keywords Waxy corn； Fresh ear yield； Agronomic character； Principal component analysis； Correlation analysis

糯玉米起源于中國，其淀粉含量高达70%～75%，几乎都为支链淀粉，在我国主要用作鲜食。近年来，随着社会经济的发展，农业部编制了《全国种植业结构调整规划（2016—2020年）》，提出优化玉米品种结构，适当发展鲜食玉米，这就给鲜食玉米产业带来了良好的发展机遇。鲜食玉米具有极高的营养价值，是集果、蔬、饲于一体的经济型专用玉米[1]。多年来各地主要种植糯玉米农家种或地方品种，其杂交育种研究起步较晚，直到20世纪70年代才开始糯玉米的杂交育种工作[2，3]，主要采用轮回选择法，将普通优良玉米自交系转育成同型糯玉米自交系，再杂交育成糯玉米杂交种，并在生产上大面积推广。