土壤微生物和氮添加对柠条根际微生境及根系形态的调控作用  

Regulating Effects of Soil Microorganisms and Nitrogen Addition on Rhizosphere Microhabitat and Root Morphology of Caragana korshinskii

作　　者：张盛晰 何炎红[1] 郝龙飞 聂正英 刘婷岩 王云鹏 滑永春 Zhang Shengxi;He Yanhong;Hao Longfei;Nie Zhengying;Liu Tingyan;Wang Yunpeng;Hua Yongchun(College of Forestry,Inner Mongolia Agricultural University,Hohhot 010019;Pinus tabuliformis National Seed Base of Wanjiagou Forestry Farm,Hohhot 010010;Inner Mongolia Academy of Forestry Sciences,Hohhot 010019;Aohanqi Forestry and Grassland Bureau,Chifeng 024314)

机构地区：[1]内蒙古农业大学林学院,呼和浩特010019 [2]万家沟林场国家油松良种基地,呼和浩特010010 [3]内蒙古自治区林业科学研究院,呼和浩特010010 [4]敖汉旗林业和草原局,赤峰024314

出　　处：《林业科学》2024年第9期80-89,共10页Scientia Silvae Sinicae

基　　金：内蒙古农业大学青年教师科研能力提升专项(BR220136);内蒙古自治区硕士研究生科研创新项目(S20231105Z);内蒙古自治区高等学校科学研究项目(NJZY22527);内蒙古自治区科技计划项目(2022YFDZ0030);呼和浩特市重大科技专项(2022-社-重-4-2)。

摘　　要：【目的】探究氮沉降背景下土壤微生物对柠条根际微生境特征的影响,探明微生境变化对柠条根系形态构建的调控规律,为脆弱生态系统的生态修复提供理论依据。【方法】在土壤灭菌处理(灭菌土和非灭菌土)基础上,对1年生柠条盆栽苗木进行接菌和未接菌试验,并设置3个氮添加[不施氮(0N)、低氮(LN)和高氮(HN)]处理。生长季结束后,对比分析各处理的土壤微生物生物量、土壤养分转化相关酶和土壤养分等指标以及苗木细根形态变化,探究微生态环境变化与根系形态构建的关联性。【结果】1)在不施氮和低氮处理中,非灭菌土处理的柠条根际土壤微生物生物量碳含量均显著高于灭菌土处理;在高氮处理中,灭菌土处理的柠条非菌根苗土壤微生物生物量碳含量最低。在不同氮添加处理中,灭菌土处理的柠条菌根苗根际土壤碳转化相关酶活性均高于非菌根苗(P<0.05),而非灭菌土处理和接菌处理交互作用下的柠条根际土壤可溶性碳含量高于单一处理(P<0.05)。2)在不同氮添加处理中,非灭菌土处理下柠条非菌根苗根际土壤微生物生物量氮含量显著高于灭菌土处理(P<0.05);非灭菌土处理和接菌处理交互作用下的柠条根际土壤氮转化相关酶活性显著高于单一处理(P<0.05)。在低氮和高氮处理下,土壤灭菌处理的非菌根苗根际有效氮含量显著高于其他处理(P<0.05)。3)在高氮处理中,非灭菌土处理和接菌处理交互作用下的柠条根际土壤微生物生物量磷含量和碱性磷酸酶活性显著高于其他处理(P<0.05),且柠条根际土壤有效磷含量介于非灭菌土处理和接菌处理的单一作用之间。4)在高氮处理中,灭菌土处理的柠条菌根苗各根系形态指标最大;而不施氮处理中,非灭菌土处理的柠条非菌根苗各根系形态指标最小。5)冗余分析表明,影响苗木根系形态的关键因子中解释度最大的为微生物生物�【Objective】This study aims to explore the influence of soil microorganisms on the rhizosphere microbiota characteristics of Caragana korshinskii under nitrogen deposition background,and explore the regulatory rules of microbiota changes on the morphological construction of C.korshinskii root system,so as to provide theoretical basis for ecological restoration of fragile ecosystems.【Method】On the basis of soil sterilization treatment(sterilized soil(+S)and non-sterilized soil(-S)),1-year-old potted C.korshinskii seedlings were subjected to two kinds of inoculation experiments(mixed inoculation with Rhizophagus intraradices and Funneliformis mosseae(+M),and non-inoculation treatment(-M)),and three nitrogen addition treatments(no nitrogen application(0N,0 g·m^(-2)a^(-1)),low nitrogen(LN,3 g·m^(-2)a^(-1)),high nitrogen(HN,6 g·m^(-2)a^(-1))).After the end of the growing season,the soil microbial biomass,soil enzymes activity related to nutrient conversion,soil nutrient content,and seedling fine root morphology with diameter≤0.5 mm(total root length,total surface area,total volume and number of root tips)of each treatment were analyzed,the correlation between micro ecological environment changes and root morphology construction was explored.【Result】1)In both 0N and LN treatments,the microbial biomass carbon content in rhizosphere soil of C.korshinskii in non-sterilized soil was higher than that in sterilized soil.In HN treatment,the soil microbial biomass carbon content of non-mycorrhizal seedlings was the lowest in sterilized soil.In sterilized soil with different nitrogen addition treatments,the activity of carbon conversion related enzymes in rhizosphere soil of mycorrhizal seedlings was higher than that of non-mycorrhizal seedlings(P<0.05),while the soluble carbon content in rhizosphere soil of C.korshinskii in non-sterilized soil and inoculation treatment was higher than that in the single treatment(P<0.05).2)Under different nitrogen addition treatments,the nitrogen content of rhizosphere soil mic

关 键 词：柠条 土壤灭菌 苗木接菌 氮添加 根际微生境 根系形态 

分 类 号：S714.3[农业科学—林学]