摘要
【目的】为探明坡耕地实施等高反坡阶水土保持措施对玉米苗期根系分泌物和土壤酶活性的影响,以期为红壤坡耕地治理及提高作物产量等提供理论依据。【方法】以滇中松华坝迤者小流域试验基地布设有等高反坡阶措施的玉米坡耕地为研究对象,原状坡耕地对照。通过CH2Cl2萃取,利用气相色谱/质谱联用仪(GC-MS)测定玉米苗期根系分泌物,分析其种类和相对含量差异的特征;探明等高反坡阶措施下玉米根系分泌物对根际土壤酶活性的响应。【结果】等高反坡阶和原状坡耕地玉米苗期根系分泌物中均含有烃类、酸类、酮类、醛类、醇类、酚类和酯类等化合物,其中烃类和酸类化合物种类最多。坡耕地布设等高反坡阶措施后改变了玉米苗期根系分泌物的种类和相对含量,有效提高了酸类化合物相对含量,显著增加玉米根际土壤脲酶、蔗糖酶、过氧化氢酶和磷酸酶的活性(P<0.05),同时根系分泌物总量与土壤酶活性呈极显著正相关(P<0.01)。【结论】等高反坡阶措施改变玉米根系分泌模式,增加了根系分泌物的种类、含量以及土壤酶活性,对玉米的生长发育具有一定促进作用。
【Objective】The objective of this study was to investigate the effects of soil and water conservation measures for contour reverse-slope terrace on maize seedling root exudates and soil enzyme activities,and then provide a theoretical basis for the management of red soil sloping farmland and the increase of crop yields.【Method】The sloping maize farmland in undisturbed control plot and contour reverse-slope terrace in the small watershed test base of Songhuaba in the middle of Yunnan is taken as the research object.In this experiment,the root exudates of maize at the seedling stage were extracted by CH2Cl2 and determined by GC-MS to analyze species and relative contents.The response of maize root exudates to rhizosphere soil enzyme activities under the contour reverse-slope terrace was investigated.【Result】It was found that hydrocarbons,acids,ketones,aldehydes,alcohols,phenols,esters and other compounds were detected in both contour reverse-slope terrace and undisturbed control plot,with hydrocarbons and acid compounds being the dominant ones.The types and relative content of root exudates at the seedling stage of maize were changed after arrangement of contour reverse-slope terrace on slope farmland,effectively increased the relative content of acid compounds,and significantly enhanced the activities of the soil urease,sucrase,soil catalase,acid phosphatase in the maize rhizosphere(P<0.05).The total amount of root exudates demonstrated a significant positive correlation with soil enzyme activities(P<0.01).【Conclusion】Contour reverse-slope terrace is able to change the mode of maize root exudation,increase the root exudates and soil enzyme activities,and promote the growth of maize.
作者
刘晓微
王克勤
赵洋毅
段旭
张洋
LIU Xiaowei;WANG Keqin;ZHAO Yangyi;DUAN Xu;ZHANG Yang(College of Ecology and Environment,Southwest Forestry University,Kunming 650224,China;College of Forestry,Southwest Forestry University,Kunming 650224,China)
出处
《四川农业大学学报》
CSCD
北大核心
2021年第4期477-485,共9页
Journal of Sichuan Agricultural University
基金
云南省基础研究计划面上项目(202001AT070136)
云南省教育厅研究生基金项目(2020Y0390)
云南省万人计划青年拔尖人才专项(YNWR-QNBJ-2019-215)。
关键词
等高反坡阶
坡耕地
根系分泌物
土壤酶活性
GC-MS
contour reverse-slope terrace
sloping farmland
root exudates
soil enzyme activity
GC-MS
