论文部分内容阅读
通过把大田试验结果同茎秆和根系结合起来，研究了４种冬小麦品种的次生根性状对倒伏抗性的效应。各品种表现出不同强度的倒伏抗性。品种Ｗｉｄｇｅｏｎ最易倒伏，其次是Ｇａｌａｈａｄ，再次是Ｒｉｂａｎｄ，而Ｈｅｒｅｗａｒｄ不倒伏。倒伏抗性同茎秆的强度与刚度联系不大，茎秆的强度与刚度一般只对抵抗所受外力有作用．大多数植株交替穿插在土壤中的根系太弱。倒伏抗性同短而轻的茎秆有联系（因植株自重与风作用于茎秆下的力较小），也同根系在土壤中的固定强度有联系．倒伏通常发生在灌浆期小麦穗最重时或土壤过潮湿时。植株固定强度取决于根系的两个性状：即抗弯强度和次生根的伸展角度。具有较壮和伸展角度较大的次生根的植株，即使在根系减弱时，也能在植株根部形成较大的根系－土填锥体（下文作“根土锥体”），从而能抵抗较大的外力作用，达到抗倒伏的效果。因此，未来的抗倒伏育种应该继续选择茎秆较短、次生根硬而结实且伸展角度较大的植株。
The effects of secondary root traits on lodging resistance of four winter wheat cultivars were studied by combining field test results with stalks and roots. All varieties showed different strength of lodging resistance. Variety Widgeon the most prone to lodging, followed by Galahad, Riband again, while Hereward does not lopsided. Lost resistance with the stalk strength and stiffness is not related to the strength and stiffness of the stalk generally only resistance to external forces have a role. The roots of most plants crossing the soil alternately are too weak. Lodging resistance is associated with short and light stalks (due to the lesser force of plant self-weight and wind acting on the stalks), but also to the fixation strength of roots in the soil. Lodging usually occurs during the filling stage when the ear of wheat is heaviest or the soil is damp. Plant fixed strength depends on two traits of the root system: flexural strength and secondary root elongation angle. Plants with stronger and more elongated secondary roots also formed larger root-soil cones (hereinafter referred to as “root cone”) at the root of plants even when the root system weakened, Large external force, to lodging the effect of lodging. Therefore, the future of lodging resistance breeding should continue to choose shorter stems, secondary roots hard and strong and stretching point of the larger plants.