| 摘要: |
| 【目的】揭示中国沙棘根蘖能力及非结构性碳水化合物（NSC）积累特征对平茬高度的响应规律，确定最有利于根蘖及NSC积累潜力发挥的平茬高度，探讨根蘖能力调控的NSC积累与分配策略。【方法】以15 a中国沙棘人工林为研究对象，设置不平茬（对照）和平茬高度0，10，20 cm 3个处理，采用回归分析探究根蘖能力（根蘖植株数量和生长量、根系延伸能力和分枝强度）、各构件（叶片、枝条、树干、伐桩、垂直根、水平根）非结构性碳水化合物的积累能力（含量、储量）和分配格局与平茬高度的关系，采用相关性分析和通径分析探究非结构性碳水化合物积累能力与根蘖能力的因果关系及其作用途径。【结果】① 随着平茬高度的增大，中国沙棘根蘖能力和NSC积累能力先升后降，最有利于根蘖能力和NSC积累潜力发挥的适宜平茬高度为10～13 cm。② 平茬后，中国沙棘各个构件NSC含量以及叶片、垂直根、水平根NSC储量与其分配比例大多大于或显著大于对照。③ 中国沙棘根蘖能力与NSC积累能力呈正相关，根蘖植株数量、生长量与根系延伸能力、分枝强度呈正相关。其中，树干和水平根的NSC储量对根蘖植株数量起主导作用，叶片和垂直根的NSC储量对根蘖植株生长量起主导作用。【结论】中国沙棘通过NSC含量、储量及其分配格局调节对平茬高度做出响应，从而决定根蘖潜力的发挥程度。由于NSC积累能力随沙棘平茬高度的增大先升后降，因此根蘖能力亦呈先升后降趋势。在此调节过程中，沙棘叶片、水平根、垂直根NSC积累能力与分配比例的提高对其根蘖潜力发挥起着关键作用。 |
| 关键词: 平茬高度 根蘖能力 非结构性碳水化合物 中国沙棘 |
| DOI： |
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| 基金项目:国家自然科学基金项目(30371193,31070551,31570609) |
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| Response of root suckering ability and non-structural carbohydrates accumulation of Chinese sea buckthorn to stubble height |
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TIAN Dengjuan,NIE Kaihong,ZHANG Zengyue,et al
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| Abstract: |
| 【Objective】The response of root suckering ability and non-structural carbohydrate (NSC) accumulation characteristics of Chinese buckthorn to stubble height was analyzed,the stubble height most favorable for root suckering and NSC accumulation potential was determined,and NSC accumulation and allocation strategies regulated by root suckering ability were explored.【Method】The 15 a Chinese sea buckthorn plantation forest was selected to set treatments of no stumping (the control) and stubble heights of 0,10 and 20 cm.Regression analysis was used to explore relationships of root suckering ability (number of suckering,growth,root extension capacity and branching strength),accumulation capacity (content and storage) and distribution pattern of non-structural carbohydrates for each component (leaves,branches,trunk,felling stumps,vertical roots and horizontal roots) with stubble heights.The causal relationship between non-structural carbohydrate accumulation capacity and root tiller capacity as well as working pathways were also explored using correlation analysis and pathway analysis.【Result】① With the increase of stubble height,the root suckering ability and NSC accumulation capacity of Chinese buckthorn increased first and then decreased.The suitable stubble height favorable for root suckering ability and NSC accumulation potential was 10-13 cm.② After flat stubble,NSC contents of Chinese sea buckthorn and NSC storages and distribution ratios of leaves,vertical roots and horizontal roots were mostly greater or significantly greater than those of the control.③ Chinese buckthorn root suckering ability was positively correlated with NSC accumulation capacity,and number and growth of root suckering plants were positively correlated with root extension capacity and branching strength.NSC storages in trunk and horizontal roots played a dominant role in the number of root suckering plants,and NSC storages in leaves and vertical roots played a dominant role in the growth of root suckering plants.【Conclusion】Chinese buckthorn responded to flat stubble height by regulating NSC content,storage and distribution pattern,so as to determine the levels of root tiller potential.NSC accumulation capacity and root suckering ability increased first and then decreased with increasing stubble height.In the regulation processes,the improvement of NSC accumulation capacity and distribution ratio in leaf,horizontal root and vertical root played a key role in enhancing root tiller potentials. |
| Key words: stubble height root suckering ability non-structural carbohydrate Hippophae rhamnoides ssp. sinensis |
