小麦抗倒伏性能测试与评价的研究

抗倒是小麦高产育种的主要目标，抗倒鉴定是育种的必要环节。目前我国对抗倒力矩和茎秆弹性等指标缺少简便、准确的测量仪器，小麦品种抗倒性鉴定基本处在以株高等直观指标为主的水平。利用最新设计的小麦抗倒电子测量仪测出的基部茎段最大抗折力矩和临界弯曲角，结合株高、重心高和茎秆重力等重要指标，采用临界分析法计算小麦最大风载荷力，以此为抗倒指数，以区域试验对照品种作对照，以10％差异作为分级标准，将抗倒指数划分为5个等级，根据抗倒级别判定抗倒性大小。分析并提出了主茎与分蘖按1：2取样，密度为600万穗／hm^2，在子粒形成期测量，初步构建了小麦茎秆抗倒性能评价体系。用该体系评价小麦茎秆抗倒性能具有相对全面、准确、客观和明了的优点，对抗倒伏研究和高产育种都具有一定的参考价值。

Research on the Measurement and Evaluation of Lodging-resistance of Wheat

Lodging is the main object of high-yield wheat breeding, and evaluation of lodging is very necessary for the breeding. So far, there is not a simple and accurate instrument to measure the moment of lodging .and stem elasticity in China. The evaluation of wheat lodging is mainly through measuring the visual indicator, like the plant height. In this study, a new electric instrument of measuring wheat lodging is used to measure the largest bending moment and the critical bending angel at the base of stem. Combined with the important indicators like the plant height, the height of gravity center, the gravity of stem, the measured values are used to calculate the biggest weather load with the criti- cal method. And this weather load is defined as the lodging resistance index. With this index, comparing the regional experimental check vari- ety, and using the 10% difference as the grade scale, we divide the lodging indicator to be 5 scales and different scales are used to evaluate the lodging resistance. In addition, we use the sample of the main stem and tillering in ratio of 1 ： 2 to do the analysis and the density is six mil- lion-ears/hm^2 , and a wheat lodging resistance performance evaluation system is preliminary built at the grain formative period. The system is comprehensive, accurate, objective and clear for evaluating the wheat lodging resistance, and is a great reference for the lodging research and high yield breeding.