鮮食型糯玉米新品種主要農藝性狀的相關和主成分分析

陳冰潔+呂瑩瑩+張恩盈+張保望

摘要：為給鮮食型糯玉米新品種的綜合評價和選育提供一定理論參考，以5個優良鮮食型糯玉米品種為試材，對其株高、穗位、穗重、穗粗、軸粗、穗長、禿尖長、穗行數、行粒數、百粒重、鮮穗產量、雄穗長、雄穗分枝13個性狀進行相關和主成分分析。結果表明：玉米鮮穗產量與穗重、百粒重、穗粗、行粒數、穗長等性狀有極顯著正相關關系。對鮮食型糯玉米13個農藝性狀進行主成分分析，顯示前三個主成分，即鮮穗產量因子、雄穗因子和禿尖長因子，其累計貢獻率達87.2767%，可以基本代表13個性狀所代表的遺傳信息。第一主成分是優良玉米品種選擇和評判的主要指標，各性狀應具備：果穗大，穗粗且軸細，即籽粒要深，穗粒數要多，百粒重要高，株高宜較高等。從第二主成分來看，鮮食玉米品種植株的雄穗最好較長，分枝不宜太多，在保證玉米雌穗對雄穗花粉量需求的同時，盡量選擇雄穗分枝少的品種。從第三主成分來看，禿尖長影響了鮮食玉米的商品品質，在品種評價和選育時，應將禿尖長度控制在最低標準。

關鍵詞：糯玉米；鮮穗產量；農藝性狀；主成分分析；相關分析

中圖分類號：S513.01 文獻標識號：A 文章編號：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，其淀粉含量高達70%～75%，幾乎都為支鏈淀粉，在我國主要用作鮮食。近年來，隨著社會經濟的發展，農業部編制了《全國種植業結構調整規劃（2016—2020年）》，提出優化玉米品種結構，適當發展鮮食玉米，這就給鮮食玉米產業帶來了良好的發展機遇。鮮食玉米具有極高的營養價值，是集果、蔬、飼于一體的經濟型專用玉米[1]。多年來各地主要種植糯玉米農家種或地方品種，其雜交育種研究起步較晚，直到20世紀70年代才開始糯玉米的雜交育種工作[2，3]，主要采用輪回選擇法，將普通優良玉米自交系轉育成同型糯玉米自交系，再雜交育成糯玉米雜交種，并在生產上大面積推廣。