玉米品种抗倒能力差异及其机制研究

Studies on variences of the lodging-resistant ability and the mechanism in different maize varieties

系统研究不同抗倒伏能力玉米品种茎秆及根系的形态、干物质和生理特性的差异,揭示玉米倒伏机制,为玉米抗倒伏高产栽培和育种提供理论依据。以2012年吉林省主导11个玉米品种为试验材料,在倒伏后第2天调查不同玉米品种的田间倒伏特征及倒伏率,各品种取整株玉米,测定株高、穗位高、气生根数量和质量;对茎秆不同节位进行分割,测定各节间长、粗、鲜质量、干质量、节间强度、木质素、纤维素、可溶性糖及微量元素含量;成熟期测定玉米籽粒产量。结果表明:玉米品种‘良玉99’穗位高系数较低,穗位下茎秆平均节间短、节间直径大、单位节间干质量较大,有较强的气生根系统;‘先玉335’和‘郑单958’抗倒伏能力弱于‘良玉99’,但其产量较高,尤其‘郑单958’,倒伏对其产量影响较小。‘良玉99’地上和地下这种双重的优良特性使得其在自然灾害面前表现出超强的抗倒伏能力,但产量仅处于中游水平。结论:在选择玉米抗倒伏品种时,应综合考虑形态和生理指标,合理密植、施肥,以降低倒伏的风险,保证玉米生产潜力得到充分发挥。

In this study,the differences of morphology of stem and roots,dry weight and physiological property of corn varieties with different lodging-resistance capability were studied systematically to reveal the mechanism of corn lodging and provide theory basis for high yield with lodging-resistant corn cultivation and breeding.On 28 th August,2012,there was a＂Bolaven＂typhoon attacked middle west part of Jilin Province,and lots of aces corn fell over.Research group went to survey the characters and rate of lodging in the11 mian corn varieties（Liangyu99,Liangyu88,Liangyu66,Nonghua101,Dika516,Jidan50,Xianyu335,Zhengdan958,Limin33,Yinhe32 and Yinhe33） after the typhoon. The lodging of maize was investigated and the morphology,dry matter and physiological characteristics of stalk and root were measured,and the variances of different variety and effects of lodging on yield were analysed.The field investigation showed that most of corn varieties except‘Liangyu99＇were in the lodging and the rate of lodging was almost100%.The stalk below the ear in‘Liangyu99＇had the following features： the lower coefficient of ear-height,the shorter internode,the bigger diameter,the higher ratio of dry weight to the length,and the stalk strength from 1st to 3rd internode above base were the highest and the number of brace root was the most in all maize varieties.In the aspect of physiological characteristics,the content of soluble sugar,ligin,Si and Zn of all internodes below the ear in‘Liangyu99＇and‘Zhengdan958＇were higher significantly than others,and those of‘Yinhe32＇and‘Yinhe33＇were the lowest.There was significant difference in the Ca and Mg content of all varieties,and the content of cellulose,N,K of‘Yinhe32＇and‘Yinhe33＇were lower than others. The yield of‘Liangyu99＇was far lower than yield of‘Xianyu335＇and‘Zhengdan958＇.The yield of‘Zhengdan958＇was not sensitive to lodging in the filling stage.‘Liangyu99＇showed great characters of both over ground and under ground which make it show great capability of lodging resistance when facing the natural hazard,while the yield only lie in the middle level.When choosing the corn varieties with lodging resistance,both morphological and physiology indexes should be taken into consideration synthetically,and rational close planting and fertilization should be applied to decrease the risk of lodging and guarantee the yield potential.