| 摘要: |
| 【目的】研究群体密度对玉米茎秆强度及相关生理指标的影响，以揭示玉米倒伏机制，为玉米抗倒伏高产栽培和育种提供理论依据。【方法】以抗倒伏性能不同的2个玉米品种先玉420(抗倒伏性能差)和益丰29(抗倒伏性能好)为试验材料，设定5，6，7，8，9，10和11万株/hm2 7个群体密度处理，分别在抽雄期(07-23)和灌浆初期(08-05)，测定玉米基部向上第3，4和5节间木质素含量及关键合成酶活性和茎秆强度，同时分析茎秆强度与各项生理指标的相关性。【结果】随着群体密度的增加，2个玉米品种第3到第5节各项指标均呈现先增加后降低的变化，第3和第4节各项指标随群体密度的变化较第5节敏感；益丰29各节位茎秆抗折断力和生理指标总体优于先玉420。相关分析表明，玉米茎秆强度与各生理指标的相关性因品种和生育时期不同而不同；益丰29茎秆强度与木质素含量、苯丙氨酸解氨酶(PAL)活性和酪氨酸解氨酶(TAL)活性呈现显著正相关，而先玉420茎秆强度则仅与TAL活性存在显著正相关。【结论】过高的群体密度会降低玉米的茎秆强度，从而减弱其抗倒伏性能。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，保证优良玉米品种的生产潜力得到充分发挥。 |
| 关键词: 玉米 群体密度 茎秆强度 木质素 抗倒伏 |
| DOI： |
| 分类号: |
| 基金项目:国家科技支撑计划项目(2011BAD16B10,2012BAD04B02)；国家自然科学基金项目(31000687)；吉林省现代农业产业技术体系建设项目(201203)；吉林省科技支撑计划项目(20130305032NY) |
|
| Effects of population density on strength and related physiological indexes of maize stalk |
|
HUANG Hai,CHANG Ying,WU Chun-sheng,et al
|
| Abstract: |
| 【Objective】Effects of population density on strength and related physiological indexes of maize stalk were studied to improve the cultivation and breeding of high-yield maize with strong lodging resistance.【Method】Xianyu 420 and Yifeng 29 with different lodging resistances were used as the test materials and seven density treatments (5,6,7,8,9,10 and 11×104 plant/hm2) were applied.At the tasseling stage (07-23) and filling stage (08-05),the stalk strength,ligin content and activities of key enzymes including phenylalanine ammonia-lyase (PAL),tyrosine ammonia-lyase (TAL) and cinnamyl alcohol dehydrogenase (CAD) at the 3rd,4th and 5th internodes above basal part of stalk were measured.And the correlation between stalk strength and all indexes were analyzed.【Result】All indexes of 3rd,4th and 5th internodes increased firstly and then decreased as the increase of population density in both maize varieties.And all indexes of the 3rd and 4th internodes were more sensitive than those of the 5th internode.Strength and physiological indexes of Yifeng 29 were better than those of Xianyu 420.The changes of all indexes at different internodes of each variety and growth stage were different.The correlation analysis showed that the stalk strength of Yifeng 29 had positive significantly correlation with ligin content,the activities of PAL and TAL,while the strength of Xianyu 420 had significantly positive correlation with TAL activity only during two growth stages.【Conclusion】High density reduced stalk strength and the lodging-resistance.Thus,the morphology and physiological characteristics should be considered when choosing maize variety and the plants should be rational planted. |
| Key words: maize population density stalk strength ligin lodging resistance |
