豆禾混播对丛枝菌根真菌群落及氮素吸收的影响  

Effects of Legume-Grass Mixtures on Soil Arbuscular Mycorrhizal Fungi Community and Plant Nitrogen Uptake

作　　者：李香君 弓晋超 李旭旭 马骢毓 刘琳[1] 孙飞达[1] 周冀琼 LI Xiangjun;GONG Jinchao;LI Xuxu;MA Congyu;LIU Lin;SUN Feida;ZHOU Jiqiong(Grassland Science and Technology College,Sichuan Agricultural University,Chengdu 611130,China)

机构地区：[1]四川农业大学草业科技学院,四川成都611130

出　　处：《中国草地学报》2023年第7期71-80,共10页Chinese Journal of Grassland

基　　金：国家自然科学基金面上项目(32271776);川藏铁路废渣堆生态修复项目(343-2222339002);四川省青年基金项目“改良方式对草地生物多样性与生态系统多功能性的影响机制”(2022NSFSC1769)共同资助。

摘　　要：丛枝菌根真菌是一种土壤有益真菌,能与植物形成共生关系,对植物养分吸收方面起着至关重要的作用。为了探究豆禾混播草地对AMF群落及氮养分吸收的影响,本试验在川西南建立鸭茅+白三叶+红三叶混播草地,对比混播处理与各单播对照中土壤AMF群落及植物氮素吸收变化机制。结果表明:1)混播中鸭茅全氮含量比鸭茅单播高57.94%,全磷含量在单播和混播中没有显著变化。混播中鸭茅δ^(15)N值显著提高,比单播鸭茅高31.04%,且鸭茅植物全氮、δ^(15)N值与菌丝密度呈正相关关系;2)混播中豆科植物固氮量比单播白三叶高103.59%、比单播红三叶高70.33%,且固氮量和菌丝密度呈显著正相关关系;3)侵染率在单播和混播中差异不显著,但混播中孢子密度及菌丝密度显著高于单播;4)混播中土壤铵态氮、微生物生物量氮显著高于单播,而单播红三叶土壤中的硝态氮含量最高。我们的试验证明了,豆禾混播草地的建植将会增加土壤中的菌丝密度和孢子密度,促进豆科植物的固氮量与禾本科植物的养分吸收。As soil beneficial fungi,arbuscular mycorrhizal fungi(AMF)establish symbiotic associations with plants,playing a crucial role in plant nutrient uptake.This study aimed to investigate the soil AMF community and plant nitrogen uptake in a legume-grass mixture grassland.In this study,a legume-grass mixture artificial grassland comprising Dactylis glomerate,Trifolium repens,and Trifolium pretense was established in southwest Sichuan.The results showed that in the mixed sowing treatment,the total nitrogen content of D.glomerate was 57.94% higher compared to the monoculture treatment,with no significant change in total phosphorus content between the two treatments.The δ^(15)N value of D.glomerate in mixed sowing treatment was significantly higher,showing an increase of 31.04% compared to the monoculture treatment.Moreover,the total nitrogen content andδ15N value of D.glomerate exhibited a positive correlation with AMF hyphae density.In terms of nitrogen fixation,legumes in mixed sowing treatment demonstrated a 103.59% higher nitrogen fixation rate than T.repens alone and a 70.33% higher than T.pretense alone.There was a significant positive correlation between nitrogen fixation and hyphae density.Furthermore,the mixed sowing treatment significantly increased the nitrogen fixation capacity of T.repens and T.pretense by 103.59% and 70.33%,respectively,compared to the legume monoculture treatment,Nitrogen fixation rate also displayed a positive correlation with hyphae density.Root colonization did not show significant differences between the monoculture and mixed sowing treatments,while spore density and hyphae density were significantly higher in the mixed sowing treatment.Additionally,soil ammonium nitrogen and microbial biomass nitrogen were significantly higher in the mixed sowing treatment compared to the monocultures.The highest nitrate nitrogen content was found in the monocultures of T.pretense.In conclusion,the establishment of grass-legume mixtures enhanced spore density and hyphae density in the soil,thereby

关 键 词：豆禾混播 AMF ^(15)N标记 养分吸收 

分 类 号：S54[农业科学—作物学]