摘要
试验采集未种植、种植1年、3年和5年的黄花蒿根际土壤,采用常规分析和Illumina MiSeq高通量测序技术,研究了土壤微生物生物量、酶活性及真菌群落组成。结果表明,在人工种植黄花蒿的土壤中,微生物生物量碳氮减少,碳氮比例改变;脱氢酶、脲酶和蔗糖酶活性降低,酸性磷酸酶活性增强;说明黄花蒿释放的化感物质选择性抑制了土壤微生物生长、繁殖和代谢。在不同种植年限的土壤中,主成分分析显示代表不同种植年限土壤真菌群落的点在坐标图中分布距离较远,表明它们的群落组成发生了显著变化(P<0.05)。此外,子囊菌门占土壤真菌的66.10%~95.28%,黄花蒿种植时间影响真菌门类和优势真菌的丰富度。在前20种优势真菌中,有14种共存于不同种植年限的土壤中,每种土壤中存在1~3种独有真菌,说明土壤是决定真菌种群组成的主导因素,又因种植黄花蒿而改变。在栽培1~5年的黄花蒿土壤中,优势菌株中出现蒿属的常见病菌——蒿白粉菌和艾菊柄锈菌,提高相应病害的发生风险。
Artemisia annua (Qinghao, Asteraceae) is widely grown in Chongqing, China, for extracting the antimalarial drug, artemisinin. Many research studies focus on the release of allelochemicals into soils via leaching with rainfall percolation, on root exudation, and on decomposition of dead plant residues in the growing process of A. annua and on the inhibition of the growth and development of adjacent and subsequent crops by these allelochemicals, particularly artemisinin. Soil microbes play roles in nutrient transformation, organic matter recycling, toxicant decomposition, and hormone efflux, among others. However, little is known about the influence of continuous cultivation of this medicinal plant on soil microorganism populations. Therefore, rhizospheric soils cropped with A. annua for 1, 3, and 5 years were collected and analyzed by routine methods and Illumina MiSeq pyrosequencing to study microbial biomass, enzyme activity and fungal community compo- nents. Microbial biomass carbon (C) and nitrogen (N), and enzyme activities (dehydrogenase, urease and in- vertase) decreased, while C : N in microbes varied, and acid phosphatase activity increased in soils with this medicinal plant compared that in the soil without this plant. These results suggest that allelochemicals released from A. annua into the rhizosphere inhibited the metabolism, growth and reproduction of microorganisms. Principal component coefficients of fungal communities in soils varied significantly, indicating great changes of fungal community structures. In soil fungal communities, Ascomycota was the largest group, accounting for 66.10%-95.28% of the total taxa detected, and there was a significant change in the abundance of both fungal phyla and the top species during A. annua cultivation. Among the predominant fungi, 14 species were found in all soils, and only 1-3 unique species existed in each soil, suggesting that the soil was the most important factor governing the composition of the fungal community, but that community structure is also changed by A. annua cultivation. Erysiphe artemisiae and Puccinia tanaceti, two pathogenic fungi which only infect A. annua, were found in the soils cropped with A. annua. The presence of these two pathogenic fungi in soils would increase the risk of disease incidence in A. annua. Therefore, rotation is advisable when cropping A. annua. Although our study provided some information about fungal community composition and diversity in the soil cropped with A. annua, a large number of microorganisms detected remain unidentified, and the functions of microbes classified is also not clear. T remains very poor. Further study should results confirm that the understanding of soil microbial communities focus on determining the identity and function of bacterial members of the microbial community, as these could be important in maintaining soil quality and function in cropping systems.
出处
《草业学报》
CSCD
北大核心
2017年第1期34-42,共9页
Acta Prataculturae Sinica
基金
国家973计划项目(2013CB127405)
国家科技惠民计划项目(2013GS 500102)
重庆市科技研发基地项目(cstc 2014ptyjd10001)
重庆市自然科学基金(cstc2011jjA 0861)
中央高校基金(SWU113094)资助
关键词
黄花蒿
土壤酶活性
真菌
高通量测序
Artemisia annua
soil enzyme activity
fungi
high throughput sequencing