摘要:丛枝菌根真菌 (Arbuscular mycorrhizal fungi, AMF) 在农业生态系统中具有重要功能。然而,不同杂草控制措施如何影响稻茬麦田的 AMF 群落结构目前并不清楚。本研究目的是探究杂草控制是否会改变稻茬麦田的AMF群落组成和多样性。本研究于 1998年开始,以长江中下游稻麦两熟制为研究背景进行长期实验,具体处理方式如下:(1) 无草处理区,除草剂+人工除草,灌水中有网,四周加网 (WiWaMH),(2) 无草处理区,除草剂+人工除草,灌水中无网 (MH),(3) 除草剂处理区,灌水中有网 (WaH),(4) 人工除草区,灌水中有网 (WaM),(5) 对照区,一直不除草 (CK)。本研究通过高通量测序手段获得了 AMF群落物种组成信息,同时测定了土壤理化性质数据。本文采取多重比较分析、NMDS 分析、RDA 分析和 SIMPER 分析来解析 AMF 群落结构。结果表明:硝态氮 (NO3--N)、有效磷 (AP)、含水量 (WC) 和有机碳 (SOC) 是影响 AMF 群落结构的主要土壤理化性质,其中最主要的是NO3--N;施用农药并不是本实验主要影响因素;AMF群落结构的变化主要体现在物种信息上。因此推测AMF群落结构变化可能不受杂草群落的直接影响,而是农业生态系统的整体性影响。 27440 毕业论文关键词:杂草控制;AMF群落结构;土壤理化性质;稻麦两熟制
Impact of Long-term Weed Control on AMF Community Structure in Wheat Field after Rice Reaping Student majoring in Agronomy
Abstract: Arbuscular mycorrhizal fungi (AMF) play an important role in agroecosystem. However, little is known about how different weed control methods affect AMF community structure of wheat field after rice reaping. The goal of the study is to test whether weed control will alter AMF community composition and persity of wheat field after rice reaping. The study has been based on rice-wheat cropping system of middle-lower reaches of Yangtze River for a long-term experiment since 1998. Our treatments are (1) No weed treatment plot, manual+ herbicide weeding, irrigation with a net, around the net (WiWaMH), (2) No weed treatment plot, manual+ herbicide weeding, irrigation without a net (MH), (3) Herbicide treatment plot, irrigation with a net (WaH), (4) Manual treatment plot, irrigation with a net (WaM), (5) Control plot, no weeding (CK). AMF community species information was obtained by pyrosequencing, and soil physiochemical properties data were measured. This study had taken multiple comparative analysis, NMDS analysis, RDA analysis and SIMPER analysis to analyze AMF community structure. The results showed that nitrate nitrogen (NO3--N), available phosphorus (AP), water content (WC) and soil organic carbon (SOC) were the main soil physiochemical properties affecting AMF community structure, among which the most important was NO3--N. The application of pesticide was not the main influencing factor in this experiment. The change of AMF community structure was mainly reflected on the species information. Therefore, it was speculated that the structural changes of AMF community might not be directly affected by weed community, but rather the overall impact of the agroecosystem. Key words: Weed Control;AMF Community Structure;Soil Physiochemical Properties;Rice-wheat Cropping System
目 录
摘要1
关键词1
Abstract1
Key words1
引言1
1 材料与方法2
1.1 研究地概况2
1.2 田间设计和管理2
1.3 土壤样品采集与处理3
1.4 实验方法3
1.4.1 土壤理化性质测定3
1.4.2 土壤 AMF 群落4
1.5 数据分析4
2 结果与分析4
2.1 土壤理化性质分析4
2.2 AMF 多样性分析6
2.3 NMDS 分析6
2.4 RDA 分析8
2.5 SIMPER 分析9
3 讨论10
致谢11