草业学报2025，Vol.34Issue(10)：51-61,11.DOI:10.11686/cyxb2024469
紫花苜蓿与库尔勒香梨间作体系氮素转移途径的定量分析
Quantitative analysis of nitrogen transfer pathways in intercropping systems between alfalfa and Korla pear
摘要
Abstract
The husbandry methodology of increasing nitrogen supply to Korla pear(Pyrus sinkiangensis)by planting legume forage between rows of Korla pear has been well established,but the specific pathways of nitrogen utilization and transfer under such intercropping are not clear.This study,focused on alfalfa(Medicago sativa)and Korla fragrant pear intercropping.Four nitrogen transfer pathways were established:complete root isolation(PS),inorganic nitrogen ion transfer only(NS),hyphal channel transfer(J),and no isolation(S).The 15N isotope tracing method was used to quantify the biological nitrogen fixation capacity,nitrogen transfer effciency,and influencing factors in the intercropping system,as well as to analyze the contributions of each pathway.The results showed:1)The nitrogen fixation of intercropped alfalfa was 4.74 g·m-2,which was 0.18 g·m-2,greater than mono-cropped alfalfa.2)Compared with PS,the amount of nitrogen fixation increased under S increased by 33.6%,increased under NS by 5.4%and decreased under J by 71.7%,while the amount of nitrogen transfer increased by 224.8%,119.8%and 4.7%,respectively.The nitrogen transfer efficiencies under the four pathways ranked S(0.92%)>NS(0.63%)>J(0.30%)>PS(0.28%).3)Nitrogen fixing enzyme activity had a highly significant effect on the amount of nitrogen fixation by the leguminous intercrop(P<0.01),while soil hyphal density significantly positively effect on the nitrogen fixation rate(P<0.05)and the intensity and frequency of AM fungal infestation was significantly positively correlated with the rate and amount of nitrogen transfer(P<0.05).Therefore,the nitrogen transfer pathway under intercropping of alfalfa and pear was mainly a dual pathway of inorganic nitrogen ions and AM fungal mycelium,and Korla pear gained a total of 33.61%of its total nitrogen from intercropping with alfalfa.This study offers a novel approach to enhancing nitrogen use efficiency,conserving land resources,and addressing fertilizer shortages in tree-forage tercropping system.关键词
林草间作/氮素利用效率/氮转移途径/AM真菌菌丝途径/无机离子途径Key words
forest-grass intercropping/nitrogen use efficiency/nitrogen transfer pathway/AM fungal mycelium pathway/inorganic ion pathway引用本文复制引用
明艳,窦梓镱,郑伟,王宁欣,陈雪..紫花苜蓿与库尔勒香梨间作体系氮素转移途径的定量分析[J].草业学报,2025,34(10):51-61,11.基金项目
国家自然科学基金项目(项目编号:32060402)和新疆维吾尔自治区高校科研计划重点项目(项目编号:XJEDU2019I013)资助. （项目编号:32060402）
