Distribution characteristics of the soil fungi community in the rhizosphere of foxtail millet under different planting patterns
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摘要: 为了解谷子连作对土壤真菌群落结构的影响, 以撂荒地为对照, 以谷子-玉米轮作、谷子连作3年、连作5年根际土壤为研究对象, 采用真菌ITS高通量测序技术, 探究不同种植模式下谷子土壤真菌群落分布特征。结果表明: 不同种植模式下, 谷子根际土壤共检测到真菌10门24纲46目79科136属和146种。在门和纲水平上群体结构相对稳定, 谷子田土壤优势门主要包括子囊菌门和担子菌门, 优势纲为粪壳菌纲、座囊菌纲和盘菌纲。在目水平谷子根际土壤粪壳菌目相对丰度是撂荒地的2倍以上; 在科水平和属水平轮作土壤被孢霉、球腔菌相对丰度高于连作土壤, 链格孢菌、亚隔孢壳菌和粉红螺旋聚孢霉菌相对丰度低于连作土壤。Alpha多样性分析显示, 谷子-玉米轮作与谷子连作根际土壤真菌丰度差异达显著水平(P<0.05), 轮作土壤真菌丰度最高。Beta多样性分析显示连作3年和连作5年根际土壤真菌结构相似, 与撂荒地以及轮作根际土壤真菌结构存在差异, 表明不同种植模式谷子根际土壤真菌群落结构发生了改变。相关性分析显示, 碱解氮与有机质呈极显著正相关(P<0.01), 与有效磷、脲酶活性呈显著相关(P<0.05), 多酚氧化酶活性与速效钾呈显著正相关(P<0.05), 真菌群落的Chao1指数、Observed species指数与多酚氧化酶活性呈极显著正相关(P<0.01)。冗余分析(RDA)表明, 撂荒地受毛壳菌影响, 轮作受球腔菌属和微结节霉属的影响, 连作3年和连作5年受毛葡孢属、毛喙壳属、亚隔孢壳属等影响。LEfSe分析确定了谷子根际土壤特定标志物, 轮作根际土壤的标志物包含被孢霉属和球腔菌属, 连作3年根际土壤标志物包含毛葡孢属、亚隔孢壳属和粉红螺旋聚孢霉属, 连作5年根际土壤标志物包含链格孢菌属和亚隔孢壳属。因此, 谷子-玉米轮作与谷子连作相比, 土壤真菌群落结构差异较大, 轮作土壤腐生菌较多, 连作土壤病原菌较多。Abstract: Continuous cropping obstacles occur in foxtail millet. To understand the effects of continuous cropping of foxtail millet on the soil fungal community structure, we explored the distribution characteristics of the fungal community of the rhizosphere soil using the fungal ITS high-throughput sequencing technology under different cropping strategies, including foxtail millet-maize rotation, foxtail millet continuous cropping for three years and five years, and the abandoned land taken as a control. The results showed that a total of ten phyla, 24 classes, 46 orders, 79 families, 136 genera, and 146 species of fungi were detected in the rhizosphere soil of foxtail millet under different cropping strategies. The population structure was relatively stable at the phylum and class levels. The dominant phyla in the soil mainly consisted of Ascomycota and Basidiomycota, whereas the dominant classes were Sordariomycetes, Dothideomycetes, and Pezizomycetes. At the order level, the relative abundance of Sordariales in the rhizosphere of foxtail millet was two times greater than that in abandoned land. At the family and genus levels, the relative abundance of Mortierellaceae and Mycosphaerellaceae was higher, whereas the relative abundance of Alternaria, Didymella, and Clonostachys was lower in the rotation soil than in the continuous cropping soil. Alpha diversity analysis showed that the fungal abundance of the rhizosphere soil was significantly different under foxtail millet-maize rotation and foxtail millet continuous cropping (P<0.05), and that under that rotation, soil diversity was the highest. Beta diversity analysis revealed that the fungal structures of the rhizosphere soil under continuous cropping for three and five years were similar, and they were different from those under abandoned land or rotating cropping, indicating that the fungal community structure in the rhizosphere soil of foxtail millet changed under different cropping strategies. Correlation analysis showed that alkali-hydrolyzed nitrogen was significantly positively correlated with organic matter (P<0.01) and significantly correlated with available phosphorus and urease activities (P<0.05), while the activity of polyphenol oxidase was positively correlated with available potassium (P<0.05) and significantly positively correlated with the Chao1 index and the observed species index (P<0.01). Redundancy analysis (RDA) indicated that CK were affected by Chaetomium, CR was affected by Mycosphaerella and Microdochium, TC and FC were affected by Botryotrichum, Chaetomidium, and Didymella. LEfSe analysis identified distinctly specific markers in the rhizosphere soil of foxtail millet under different cropping strategies. The markers of rhizosphere soil contained Mortierella and Mycosphaerella for the rotating cropping, Botryotrichum, Didymella, and Clonostachys for three years of continuous cropping, and Alternaria and Didymella for five years of continuous cropping. Overall, the soil fungal community structure under millet-maize rotation cropping, exhibiting more saprophytic fungi and fewer pathogenic fungi, was significantly different from that under foxtail millet continuous cropping, which provided useful information for the study of the continuous cropping obstacles of foxtail millet.
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谷子(Setaria italica)有抗旱耐瘠特性, 是我国古老的栽培作物之一, 种植面积和总产量均居世界首位[1-2]。随着全球性干旱日趋严重, 旱作农业越来越受到重视[3], 加之谷子是全谷物食物[4], 营养丰富、药食同源, 对调节我国人民膳食结构起着重要作用, 为谷子产业发展带来了新的机遇。由于土地资源稀缺, 谷农为追求经济效益最大化, 谷子连作时有发生, 由此引起的连作障碍难题也已成为制约谷子可持续发展的关键问题。
连作是导致作物产量降低、病害加重、品质下降的重要原因。不同作物连作障碍程度不同, 有的作物连作障碍较轻, 如小麦(Triticum aestivum)、玉米(Zea mays)和水稻(Oryza sative)等, 但大部分作物, 如谷子、棉花(Gossypium hirsutum)、黄瓜(Cucumis sativus)、草莓(Fragaria × ananassa)、苦参(Sophora flavescens)、黄连(Coptis chinensis)和马铃薯(Solanum tuberosum)等连作障碍严重[5-11]。造成连作障碍的原因主要有4个方面: 第一, 土壤微生态失衡, 有害微生物富积, 有益微生物种群退化[12-13]; 第二, 作物偏好的营养元素缺失, 有害元素富集, 导致土壤理化性质发生改变[14]; 第三, 作物根际分泌物累积, 产生自毒作用[15]; 第四, 连续使用相同的肥料和农药, 使得土壤出现酸化、板结等土壤退化现象, 病虫害的抗性不断增强[16-17]。其中, 土壤微生态失衡是连作障碍发生的根本原因[18]。
土壤微生物是植物-土壤生态系统重要组成, 细菌和真菌等微生物在植物生长过程中发挥重要作用。土壤真菌包含有益真菌和病原真菌, 有益真菌可促进作物对营养元素的摄取, 相比细菌而言, 能更好地降解复杂化合物[19-21]; 病原菌可入侵植物的根、茎、叶等组织器官, 并造成危害, 从而引起农作物减产或者品质下降[22-23]。谷子不同施肥条件、不同轮作方式对土壤理化性质、微生物多样性的影响已广泛开展研究[24-26]。Debenport等[27]研究表明, 谷子与灌木间作, 根际土壤微生物种群与谷子生长显著相关; Dang等[28]研究表明谷子与绿豆(Vigna radiata)间作改变了根际土壤微生物多样性; 牛倩云等[29]研究表明谷子轮作可促进土壤细菌多样性; 孙倩等[30]指出谷子与大豆(Glycine max)轮作模式下, 谷子根际微生物环境最佳。
本研究以撂荒地和连作、轮作谷子根际土壤为研究对象, 采用Illumina MiSeq高通量测序技术[31-32], 依据ITS基因测序结果, 结合土壤理化性质测定结果, 分析了不同种植模式下谷子根际土壤真菌群落结构和多样性变化, 旨在了解谷子根际土壤真菌群落、土壤理化性质与谷子连作的关系, 为克服谷子连作障碍提供理论依据, 促进有机旱作农业的可持续发展。
1. 材料与方法
1.1 试验地概况与试验设计
试验在山西农业大学谷子研究所科研基地(以下简称科研基地)进行。科研基地位于36°11′N、113°06′E, 海拔930 m。试验从2016年开始, 前茬作物为玉米。试验设4组处理, 每组处理面积为90 m2, 不设重复。4组处理分别为撂荒地(CK, 2016年开始未种植任何作物)作对照、轮作(CR, 2016年种植谷子, 谷子-玉米-谷子周年单序轮作) (CR)、谷子连作3年(TC, 2016—2017年连续2年种植玉米, 2018—2020年连续3年种植谷子)、谷子连作5年(FC, 2016—2020年连续5年种植谷子), 试验田施复合肥(N∶P∶K=10∶5∶5) 1200 kg∙hm−2和有机肥7500 kg∙hm−2, 撂荒地不施肥, 其他田间管理措施相同。
1.2 样品采集
2020年于谷子成熟期, 每组处理平分为3个采样区, 采用5点取样法对各采样区取样。每采样区取5株长势一致的谷子, 将根周5 cm的根系全部挖出, 去除表面附着土, 轻抖根系, 用软毛刷轻刷根上的根际土, 各采样区的5个样品混匀为1份, 分别置入无菌自封袋(连同样本编号), 放入冰盒, 带回实验室。在实验室, 将各样品分为两部分保存, 一部分装入离心管, 置于−80 ℃超低温冰箱, 用作微生物多样性研究; 另一部分置于实验室, 风干后置入无菌自封袋, 用于土壤理化性质测定。
1.3 土壤真菌总DNA提取与纯化
采用E.Z.N.A Soil DNA试剂盒(OMEGA公司)提取土壤样品DNA, 采用Nanodrop对DNA进行定量, 采用1.2%琼脂糖凝胶电泳检测DNA质量。采用BECKMAN AMPure XP Beads再次纯化文库富集产物, 采用 2%琼脂糖凝胶电泳, 对文库做最终片段选择与纯化。
1.4 真菌ITS1区PCR扩增与测序
采用特异性引物ITS5F: 5′-GGAAGTAAAAGTCGTAACAAGG-3′, ITS1R: 5′- GCTGCGTTCTTCATCGATGC-3′对真菌ITS r RNA的ITS-V1区进行PCR扩增。PCR产物采用 2%琼脂糖凝胶电泳检测, 用Axy Prep DNA凝胶回收试剂盒回收目的片段。采用Illumina MiSeq高通量测序平台进行样品测序。
1.5 序列获取与分析
序列获取: 采用Illumina平台对群落DNA片段进行双端测序, 采用DADA2方法[33], 去引物、质量过滤、去噪、拼接和去嵌合体等, 得到真菌ITS序列(ASV, amplicon sequence variants)。对真菌ITS比对的数据库为UNITE-8数据库。采用Qiime 2的classify-sklearn算法, 用预先训练好的Naive Bays分类器进行物种注释, 并通过稀疏曲线反映测序深度是否合适。
序列分析: 使用ASV丰度表制作韦恩图, 统计各组独有的及组间共有的ASV个数。依据序列物种分类学注释的结果, 统计各组在门、纲、目、科、属、种6个分类水平各自含有的分类单元数量。对非单丰度序列的特征表进行统计, 以柱状图呈现各组在门、纲、目、科、属5个分类水平上的组成分布。以Good’s coverage指数表征覆盖度, 以Chao1[34]和Observed species指数表征丰富度, 以Shannon 指数表征多样性, 以丰度等级曲线来反映多样性差异。基于 Bray-curtis 距离矩阵, 采用主坐标分析(Principal coordinates analysis, PCoA)[35]和通过python的scikit-bio包进行“permanova”组间差异分析来检验真菌群落的结构。利用在线软件(http://www.genescloud.cn)对土壤真菌属水平物种相对丰度与土壤理化性质的相关性进行冗余分析(RDA)。LEfSe分析设置LDA阈值为2, 筛查标志物种(biomarker)。
2. 结果与分析
2.1 不同种植模式下真菌ITS1区测序结果
为探索不同种植模式下谷子根际土壤真菌群落结构, 对土壤样品进行菌群DNA抽提, 通过Illumina Miseq高通量测序技术对真菌ITS1区进行测序分析(表1)。从4组处理12个样品中共获得1 160 414条优化序列, 每个样品有256 268~357 026条优化序列, 平均290 103条优化序列; 优化序列长度为134~438 bp, 平均长度227 bp。4组处理的稀疏曲线均趋于平坦, 说明各样品测序数据量合理, 测序深度足够(图1), 适合根际土壤真菌丰度和群落结构的进一步分析。
表 1 不同种植模式谷子根际土壤的真菌高通量测序结果Table 1. High-throughput sequencing results of fungi in foxtail millet rhizosphere soils with different cropping patterns样本 Sample 去引物 Input 质量过滤 Filtered 去噪 Denoised 拼接 Merged 去嵌合体 Nonchimeric 非单丰度序列 Nonsingleton CK1 84 027 72 625 72 198 71 545 70 622 70 622 CK2 126 381 113 085 112 560 111 845 109 959 109 959 CK3 89 761 78 138 77 541 76 793 75 687 75 687 CR1 191 960 176 283 175 227 174 315 166 205 166 205 CR2 107 110 94 546 93 956 93 200 92 359 92 358 CR3 117 377 102 500 101 873 101 068 98 463 98 463 TC1 137 752 120 634 120 061 119 468 117 184 117 184 TC2 99 344 86 259 85 673 85 041 82 241 82 241 TC3 88 864 78 645 78 247 77 656 77 136 77 136 FC1 116 128 102 142 101 466 100 870 98 526 98 526 FC2 104 460 91 841 91 398 90 841 90 022 90 022 FC3 96 306 84 106 83 632 82 980 82 011 82 011 CK: 撂荒地; CR: 谷子-玉米轮作; TC: 谷子连作3年; FC: 谷子连作5年。各处理缩写后的数据为重复。CK: abandoned land; CR: foxtail millet rotation with maize; TC: continuous cropping for 3 years of foxtail millet; FC: continuous cropping for 5 years of foxtail millet. The data after abbreviation of treatment is the replicate. ![]()
图 1 不同种植模式谷子根际土壤真菌群落的稀疏曲线CK: 撂荒地; CR: 谷子-玉米轮作; TC: 谷子连作3年; FC: 谷子连作5年。CK: abandoned land; CR: foxtail millet rotation with maize; TC: continuous cropping for 3 years of foxtail millet; FC: continuous cropping for 5 years of foxtail millet.Figure 1. Sparse curves of soil fungal community of foxtail millet rhizosphere soils with different cropping patterns2.2 不同种植模式下谷子根际土壤真菌群落结构变化
对测序结果进行聚类, 共得到2637个用于物种分类的ASV, 其中CK、CR、TC和FC的ASV分别为1014、1209、929和831个, 4组处理共有的ASV为172个(图2A)。以门、纲、目、科、属和种6个分类水平对各组处理ASV进行划分, 共检测到10门、24纲、46目、79科、136属和149种, 各组处理在门、纲、目、科、属和种分类水平下微生物类群均有差异。与撂荒地(CK)相比, 其他种植模式下谷子根际土壤(CR、TC和FC)真菌群落更丰富, 其中, 轮作土壤(CR)真菌群落最丰富(图2B)。分类等级树图(图2C)表明, 丰度前100的ASV主要分布在子囊菌门(Ascomycota)和担子菌门(Basidiomycota), 其中以子囊菌门中的ASV最多, 丰度最高的ASV也在子囊菌门中。
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图 2 不同种植模式谷子根际土壤真菌ITS序列(ASV)分类A: 不同种植模式真菌ITS序列(ASV)分布Venn图; B: 不同分类级别下不同种植模式ASV数; C: 不同种植模式谷子土壤真菌圈堆积图。CK: 撂荒地; CR: 谷子-玉米轮作; TC: 谷子连作3年; FC: 谷子连作5年。图C中, 在绘制土壤真菌分类等级树图的前提下, 将每个ASV分组的丰度数据以饼图的形式添加到了图中。展示了谷子根际土壤真菌群落分类学构成, 最大的圈代表门水平, 逐渐缩小的圈按照梯度依次代表纲、目、科、属和种, 最内层圆点面积代表ASV的丰度大小, 同时也表示该ASV在各组中的组成比例。A: Venn diagram of fungi ASV (amplicon sequence variants) of different cropping patterns; B: ASV number of different plant patterns at different classification levels; C: taxonomic tree in packed circles of soil fungi classification of foxtail millet under different cropping patterns. CK: abandoned land; CR: foxtail millet rotation with maize; TC: continuous cropping for 3 years of foxtail millet; FC: continuous cropping for 5 years of foxtail millet. For the figure C, on the premise of drawing the tree map of soil fungi classification, the abundance of each ASV group was added to the map in the form of pie chart. The largest circle represents phylum level, and the gradually shrinking circle represents class, order, family, genus and species according to the gradient. The innermost dot area represents the abundance of ASV, and also represents the composition proportion of ASV in each group.Figure 2. Amplicon sequence variants (ASV) classification of fungi of foxtail millet rhizosphere soil in different planting patterns在门、纲、目、科、属水平, 对4组处理土壤真菌群落的组成和丰度进行分析。门分类水平上, 相对丰度前3的有子囊菌门(70.48%~83.56%)、担子菌门(3.27%~7.27%)和被孢霉门(Mortierellomycota, 3.41%~6.37%), 其他门如壶菌门(Chytridiomycota)、球囊菌门(Glomeromycota)、油壶菌门(Olpidiomycota)、捕虫霉门(Zoopagomycota)、毛微门(Mucoromycota)、梳霉门(Kickxrllomycota)和罗兹菌门(Rozellomycota)相对丰度占比较少。轮作土壤(CR)中被孢霉门相对丰度高于连作土壤(TC和FC), 子囊菌门相对丰度低于TC和FC; 另外, 在TC中并未发现梳霉门、罗兹菌门和油壶菌门, FC中未发现梳霉门(图3A)。
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图 3 不同种植模式谷子根际土壤真菌在不同分类水平的相对丰度A-E表示分类单元在门、纲、目、科和属水平上的百分比。CK: 撂荒地; CR: 谷子-玉米轮作; TC: 谷子连作 3 年; FC: 谷子连 作 5 年。Figure A-E show the percentage of taxa at the phylum, class, order, family, and genus levels. CK: abandoned land; CR: foxtail millet rotation with maize; TC: continuous cropping for 3 years of foxtail millet; FC: continuous cropping for 5 years of foxtail millet.Figure 3. Relative abundance of fungi in foxtail millet rhizosphere soil under different cropping patterns at different classification levels纲分类水平上, 相对丰度前10的有粪壳菌纲(Sordariomycetes)、座囊菌纲(Dothideomycetes)、盘菌纲(Pezizomycetes)、被孢霉纲(Mortierellomycetes)、伞菌纲(Agaricomycetes)、银耳纲(Tremellomycetes)、锤舌菌纲(Leotiomycetes)、散囊菌纲(Eurotiomycetes)、黑粉菌纲(Ustilaginomycetes)和裂壶菌纲(Spizellomycetes), 其中相对丰度较高的有粪壳菌纲(53.60%~62.14%)、座囊菌纲(9.94%~13.05%)和盘菌纲(2.1%~15.98%)。与CK相比, 谷子根际土壤中盘菌纲相对丰度降低10%以上, CR中的被孢霉纲和伞菌纲相对丰度高于TC和FC, 粪壳菌纲相对丰度低于TC和FC (图3B)。
目分类水平上, 大多数真菌属于肉座菌目(Hypocreales)、粪壳菌目(Sordariales)、格孢腔菌目(Pleosporales)、盘菌目(Pezizales)、被孢霉目(Mortierellales)以及煤炱目(Capnodiales)。与CK相比, 谷子根际土壤中的粪壳菌目相对丰度增加8%以上, 盘菌目相对丰度降低10%以上。CR中肉座菌目、格孢腔菌目相对丰度低于TC、FC, 被孢霉目、煤炱目相对丰度高于TC和FC (图3C)。
科分类水平上, 相对丰度前10的有赤壳科(Nectriaceae)、毛壳菌科(Chaetomiaceae)、毛球壳科(Lasiosphaeriaceae)、生赤壳科(Bionectriaceae)、火丝菌科(Pyronemataceae)、被孢霉科(Mortierellaceae)、球腔菌科(Mycosphaerellaceae)、囊菌科(Microascaceae)、荚孢腔菌科(Sporormiaceae)和Myrmecridiaceae。与CK相比, 谷子根际土壤中的赤壳科和火丝菌科相对丰度降低, 而毛球壳科相对丰度增加。CR中毛壳菌科相对丰度低于TC和FC, 被孢霉科、球腔菌科相对丰度高于TC和FC (图3D)。
在属水平上, 对相对丰度前20的真菌进行了分析。其中与CK相比, 谷子根际土壤中的毛葡孢属(Botryotrichum)增加, TC中含量最高; CR中的被孢霉属(Mortierella)和球腔菌属(Mycosphaerella)相对丰度高于TC和FC, 链格孢属(Alternaria)和亚隔孢壳属(Didymella)相对丰度低于TC和FC; 粉红螺旋聚孢霉(Clonostachys)在TC中最高(9.95%), 在FC中较高(3.54%), CK和CR中较少, 含量分别为0.74%和0.09% (图3E)。
2.3 不同种植模式下谷子根际土壤真菌群落多样性
2.3.1 α多样性分析
为了全面评估真菌群落的Alpha多样性, 分别以Chao1、Observed species、Shannon以及Good’s coverage等指数(图4A)和丰度等级曲线(图4B)来比较不同组间的多样性差异。4组处理中的Good’s coverage数值均在99%以上, 证明处理中序列没有被测出的概率很低; Chao1和Observed species指数由高到低依次为CR>TC>CK>FC, 且差异显著(P<0.05), 说明不同种植年限谷子根际土壤真菌群落的丰富度差别较大; Shannon指数由高到低依次为TC>CR>CK>FC, 4组样品的多样性差别未达显著水平; 丰度等级曲线(图4B)表明, CR具有更高的丰富度和均匀度, TC的丰富度差异最大且均匀度较低。Alpha多样性分析表明, 谷子连作会改变根际土壤真菌群落丰富度和多样性, 其中, CR的丰富度最高, TC的多样性最高, 均匀度较低。
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图 4 不同种植模式谷子根际土壤真菌群落的Alpha多样性分析A: α多样性指数; B: 丰度等级曲线。CK: 撂荒地; CR: 谷子-玉米轮作; TC: 谷子连作3年; FC: 谷子连作5年。A: α diversity index; B: abundance grade curve. CK: abandoned land; CR: foxtail millet rotation with maize; TC: continuous cropping for 3 years of foxtail millet; FC: continuous cropping for 5 years of foxtail millet. ASV: amplicon sequence variants.Figure 4. Alpha diversity analysis of fungi community of foxtail millet rhizosphere soil under different cropping patterns2.3.2 β多样性分析
通过主坐标分析(图5A), 观察到PCo1解释了数据集中总方差的18.1%, 而PCo2解释了剩余变化的11.7%。不同处理组的生物学重复各自聚在一起, 4组处理均有差异。与CK和CR相比, TC和FC菌群结构有很高的相似性。说明谷子连作改变了土壤真菌在属水平上的结构分布, 撂荒地土壤与其他种植模式下谷子根际土壤之间的差别较大, 轮作土壤与连作土壤之间差别也较大, 连作土壤真菌结构较为相似。组间差异分析(图5B)表明, CK组内3个采样点的差异距离最小, CR与CK, TC与CK, FC与CK的组间差异距离均大于CK组内差异距离, 进一步验证了组间处理效应大于取样偏差。这些结果表明谷子在连作后根际土壤间真菌群落物种发生了改变, 同时群落组成受种植年限的影响较大, 受采样点差异的影响较小。
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图 5 不同种植模式谷子根际土壤真菌群落β多样性分析A: PCoA分析; B: 组间差异分析。CK: 撂荒地; CR: 谷子-玉米轮作; TC: 谷子连作3年; FC: 谷子连作5年。A: PCoA analysis; B: analysis of differences among four groups. CK: abandoned land; CR: foxtail millet rotation with maize; TC: continuous cropping for 3 years of foxtail millet; FC: continuous cropping for 5 years of foxtail millet.Figure 5. β diversity analysis of fungi community of foxtail millet rhizosphere soil under different cropping patterns2.4 不同种植模式下各指标相关性分析
2.4.1 土壤酶活性与理化性质的相关性分析
土壤理化性质测定结果见之前研究结果[36]。由表2可知, 土壤酶活性与理化性质存在相关性。其中, 理化性质之间的相关性为: 碱解氮与有机质呈极显著正相关(P<0.01), 与有效磷呈显著正相关(P<0.05), 有机质与有效磷呈显著正相关(P<0.05); 酶活性之间均存在显著正相关性, 其中多酚氧化酶与过氧化氢酶、蔗糖酶呈极显著正相关(P<0.01), 脲酶和过氧化氢酶也存在极显著正相关(P<0.01); 酶活性与理化性质间的相关性为: 蔗糖酶活性与pH呈显著负相关(P<0.05), 多酚氧化酶活性与速效钾呈显著正相关(P<0.05), 脲酶活性与碱解氮、有机质呈显著正相关(P<0.05)。
表 2 谷子根际土壤酶活性与理化性质的相关性分析Table 2. Correlation analysis between enzyme activity and physicochemical properties of foxtail millet rhizosphere soilpH 碱解氮
Alkaline hydrolysis
nitrogen有效磷
Available
phosphorus速效钾
Available
potassium有机质
Organic matter多酚氧化酶
Polyphenol oxidase过氧化氢酶
Catalase脲酶
Urease蔗糖酶
SucrasepH 1.000 0.466 0.521 0.303 0.314 −0.291 −0.331 −0.203 −0.616* 碱解氮
Alkaline hydrolysis nitrogen0.466 1.000 0.588* 0.272 0.906** 0.170 0.360 0.628* 0.081 有效磷
Available phosphorus0.521 0.588* 1.000 0.216 0.614* 0.012 0.024 0.281 0.131 速效钾
Available potassium0.303 0.272 0.216 1.000 0.147 0.669* 0.451 0.326 0.230 有机质
Organic matter0.314 0.906** 0.614* 0.147 1.000 0.145 0.367 0.654* 0.175 多酚氧化酶
Polyphenol oxidase−0.291 0.170 0.012 0.669* 0.145 1.000 0.855** 0.681* 0.769** 过氧化氢酶
Catalase−0.331 0.360 0.024 0.451 0.367 0.855** 1.000 0.840** 0.682* 脲酶
Urease−0.203 0.628* 0.281 0.326 0.654* 0.681* 0.840** 1.000 0.691* 蔗糖酶 Sucrase −0.616* 0.081 0.131 0.230 0.175 0.769** 0.682* 0.691* 1.000 * 表示在0.05水平差异显著, ** 表示在0.01水平差异显著。* correlation is significant at the 0.05 level; ** correlation is significant at the 0.01 level. 2.4.2 土壤真菌群落多样性指数与理化性质、酶活性的相关性分析
表3为不同种植模式下, 谷子根际土壤真菌群落多样性指数与理化性质的相关性, 由表可知, 土壤理化性质、酶活性对真菌群落多样性指数的影响不同。真菌群落多样性指数与土壤理化性质存在相关性, 但均未达显著水平。Chao1指数、Observed species指数与多酚氧化酶活性呈极显著正相关(P<0.01), 与过氧化氢酶、蔗糖酶活性呈显著正相关(P<0.05), 故Chao1指数、Observed species指数受土壤酶活性影响较大。
表 3 谷子根际土壤真菌群落多样性指数与理化性质、酶活性的相关性分析Table 3. Correlation analysis of fungi community diversity indexes with physicochemical properties and enzyme activities of foxtail millet rhizosphere soil
Chao1指数
Chao1 indexGood’s coverage指数
Good’s coverage indexObserved species指数
Observed species indexShannon指数
Shannon indexPH −0.339 0.265 −0.316 −0.108 碱解氮 Alkaline hydrolysis nitrogen −0.038 0.369 0.006 0.024 有效磷 Available phosphorus −0.105 0.381 −0.065 −0.076 速效钾 Available potassium 0.505 0.097 0.539 0.227 有机质 Organic matter −0.048 0.389 −0.002 −0.054 多酚氧化酶 Polyphenol oxidase 0.776** −0.398 0.770** 0.038 过氧化氢酶 Catalase 0.633* −0.380 0.625* 0.034 脲酶 Urease 0.348 −0.021 0.363 −0.088 蔗糖酶 Sucrase 0.613* −0.210 0.614* −0.048 *和**分别表示在P<0.05和P<0.01水平显著相关。* and ** mean significant correlation at P<0.05 and P<0.01 levels, respectively. 2.4.3 土壤真菌(属水平)群落结构与理化性质、酶活性的相关性分析
将CK、CR、TC、FC共4组处理的土壤理化性质、酶活性与属水平真菌群落进行冗余分析(图6), 结果显示, RDA1和RDA2的特征值分别为30.1%和20.74%, 碱解氮、速效钾、有机质、4种酶与RDA1轴呈正相关; pH、有效磷与RDA1轴呈负相关。CK受毛壳菌影响较大, 毛壳菌与所有理化性质和酶活性的相关性均不大。CR受球腔菌属和微结节霉属的影响较大, 与pH、有效磷、有机质、碱解氮、脲酶、过氧化氢酶呈正相关; TC和FC受毛葡孢属、毛喙壳属、亚隔孢壳属等影响较大, 与有机质、碱解氮、脲酶、过氧化氢酶、多酚氧化酶、蔗糖酶、速效钾呈正相关。
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图 6 不同种植模式谷子根际土壤真菌群落冗余分析CK: 撂荒地; CR: 谷子-玉米轮作; TC: 谷子连作3年; FC: 谷子连作5年。AN: alkaline hydrolysis nitrogen; AK: available potassium; AP: available phosphorus; OM: organic matter; PPO: polyphenol oxidase; CAT: catalase. CK: abandoned land; CR: foxtail millet rotation with maize; TC: continuous cropping for 3 years of foxtail millet; FC: continuous cropping for 5 years of foxtail millet.Figure 6. Redundancy analysis of fungi community of foxtail millet rhizosphere soil under different cropping patterns2.5 不同种植模式下谷子田间生物标志物不同
LEfSe分析(图7)设定LDA阈值为2, 确定了CK、CR、TC和FC根际土壤的22、19、8和6个生物标志物。其中CK的生物标志物包含被孢霉属; CR的生物标志物主要在担子菌门, 包含被孢霉属和球腔菌属; TC和FC的生物标志物主要在子囊菌门, TC的生物标志物包含毛葡孢属、亚格孢壳属和粉红螺旋聚孢霉属, FC的生物标志物包含链格孢菌属和亚隔孢壳属。说明4组处理的生物标志物不同。
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图 7 不同种植模式谷子根际土壤真菌群落LEfSe分析由里到外, 依次是门、纲、目、科、属和种水平, 其中实心节点代表在CK、CR、TC和FC中起重要作用的微生物类群, 空心节点表示不起重要作用的物种。CK: 撂荒地; CR: 谷子-玉米轮作; TC: 谷子连作3年; FC: 谷子连作5年。From inside to outside is the gorups at phylum, class, order, family, genus and species levels successively. Solid nodes represent that the microbial groups play an important role in CK, CR, TC and FC, while hollow nodes represent the groups do not play an important role in the four treatments. CK: abandoned land; CR: foxtail millet rotation with maize; TC: continuous cropping for 3 years of foxtail millet; FC: continuous cropping for 5 years of foxtail millet.Figure 7. LEfSe analysis of fungi community of foxtail millet rhizosphere soil under different cropping patterns3. 讨论与结论
3.1 讨论
活跃的根际微生物作为植物的第2套基因组, 在植物的生长发育过程中发挥重要作用[37-40], 土壤微生物组成及丰富度与谷子的连作障碍关系密切, 长期连作会导致病害增加, 尤其是黑斑病、叶枯病等真菌型病害[41]。
本研究发现谷子轮作土壤真菌群落多样性高于连作。在本研究中共得到2637个用于物种分类的ASV, 其中CR土壤中的ASV最多, 稀疏曲线表明在相同测序深度下, CR土壤真菌的多样性最高, α多样性分析也表明CR土壤真菌群落丰富度高于TC和FC。这与保丽美等[42]在三七(Panax notoginseng)和李锐等[5]在棉花(Goysspium spp.)上的研究结果类似, 但有些研究认为随连作年限增加, 土壤真菌种类和数量越多[43-44]。分析其原因, 酸性环境有利于真菌生长, 而本研究中连作并未导致谷子根际土壤pH显著下降, 4组处理的土壤pH均为碱性[36], 这是因为2019—2020年山西长治气候干旱, 试验田进行了数次人工灌溉(地下水偏碱性), 导致各处理土壤仅表现出轻微酸化, 没有出现随连作年限延长, 土壤真菌增多的现象。
通过对谷子不同种植模式下的土壤微生物进行高通量测序, 发现4组处理中, 在门、纲、目、科、属和种6个分类水平下微生物类群均有差异, 不同种类真菌的相对丰度发生了变化。在门水平上, 子囊菌门和担子菌门为谷子根际土壤的优势菌门, 其中子囊菌门为谷子根际土壤最丰富的门, 主要作用是分解有机质, 这与孙倩等[45]对谷子根际土壤真菌研究结果相一致。在纲水平上, 粪壳菌纲、座囊菌纲和盘菌纲为谷子根际土壤优势菌纲, 其中, 粪壳菌纲为谷子根际土壤最丰富的纲, 粪壳菌纲是子囊菌门第二大纲, 具有更快的进化速率[46]。撂荒地与谷子根际土壤在粪壳菌纲水平上差异不显著, 但在目水平, 谷子根际土壤粪壳菌目相对丰度是撂荒地的2倍以上。有研究表明, 粪壳菌目有降解纤维素及腐烂有机质的作用[47]。撂荒地多年未种植作物, 纤维素及有机质较少, 故粪壳菌目真菌少。在科水平, 轮作土壤中毛壳菌科相对丰度低于连作土壤, 被孢霉科、球腔菌科相对丰度高于连作土壤, 被孢霉科真菌多数属于腐生菌[48], 说明轮作地块有益菌要多于连作。
作物连作会导致土壤理化性质、土壤酶活性等改变[49-50], 和土壤微生物组成及丰富度密切相关[17]。本研究中轮作土壤养分高于连作土壤[36], 且碱解氮、有效磷、有机质、脲酶活性均显著正相关, 真菌群落多样性指数也受土壤理化性质、酶活性的影响, 其中Chao1指数、Observed species指数与多酚氧化酶、过氧化氢酶、蔗糖酶活性呈显著正相关, 说明谷子根际土壤真菌受酶活性影响较大, 受土壤理化性质影响较小。
连作障碍的主要原因是微生态失衡, 有益真菌减少和病原真菌增加等[11,23]。本研究发现, 在属水平, 被孢霉菌在CR中相对丰度最高, 与pH、有效磷、有机质、碱解氮、脲酶、过氧化氢酶呈正相关, 是CR的标志物。被孢霉菌属于腐生真菌, 是土壤有益微生物, 在富含有机质的土壤中丰度较高, 为土壤碳和养分转化的关键微生物[50-51]; 此外, 被孢霉可降解纤维素、半纤维素和木质素[52-54], 对改变土壤微生物的生境有一定影响。本研究中被孢霉菌在连作后相对丰度降低, 表明谷子轮作有利于有益真菌的繁殖, 连作会导致有益真菌减少。另外, 亚隔孢壳菌、链格孢霉菌在连作土壤中相对丰度较高, 推测谷子连作后病原真菌会增加。链格孢霉菌和亚隔孢壳菌均为植物病原菌, 可引起黑斑病、叶枯病等多种真菌病害[55-56], 其中一些毒素还能在体外或大鼠体内产生遗传毒性[55]。本研究中亚隔孢壳菌是TC中的生物标志物, 亚隔孢壳菌和链格孢霉菌是FC中的生物标志物, 说明谷子连作会导致病原真菌的增加, 且连作年限不同, 病原真菌的种类也有所不同。
本研究还发现, 谷子连作导致病原真菌增加的同时也会产生生防菌。粉红螺旋聚孢霉是一类重要的菌寄生菌, 这类菌可以寄生病原真菌, 抑制病原菌的侵染, 还可通过拮抗作用, 对营养物质的竞争和诱导植物抗性等多种方式抑制病害的发生与扩展[57-59], 同时具有固氮和拮抗镰刀菌作用[60]。本研究中粉红螺旋聚孢霉在CR中极少(0.09%), TC中最高(9.95%), 到FC有所降低(3.54%), 推测在谷子连作土壤中病原菌较多, 产生的生防菌也多, 且在TC中的病原菌最多, 生防菌粉红螺旋聚孢霉菌也产生的最多。
本研究还发现一个有趣的现象, 即随连作年限增加, 谷子根际土壤环境有好转的趋势。Alpha多样性分析结果显示连作改变了谷子根际土壤真菌群落丰富度和多样性, CR真菌群落丰富度最高, 随种植年限增加呈下降趋势, 且差异显著, 表明谷子连作破坏了土壤的稳定结构, 降低了土壤真菌的丰度和均匀度; 但主坐标分析显示随连作年限增加, 谷子根际土壤真菌群落有恢复趋势, TC和FC真菌群落在构成上十分相似, 与CR、CK相比, 真菌群落结构改变十分明显, 说明谷子对于连作十分敏感, 但FC与CR在PC1上的投影距离比TC与CR在PC1上的投影距离要短, 说明随连作年限的增加, 这种改变并未进一步加剧; 另外, 土壤环境因子中碱解氮、有机质、脲酶含量也是在FC中高于TC, 进一步佐证连作5年的谷子根际土壤环境有一定好转。在大豆[61-62]、怀牛膝(Achyranthes bidentata)[63]等作物上也有类似报道。
3.2 结论
本研究利用真菌ITS高通量测序技术, 探究了连作与轮作条件下, 谷子根际土壤真菌群落的分布特征。结果表明, 谷子轮作根际土壤真菌群落多样性高于谷子连作。谷子根际土壤真菌优势菌门为子囊菌门、担子菌门, 优势菌纲为粪壳菌纲、座囊菌纲以及盘菌纲; 在目水平谷子根际土壤粪壳菌目相对丰度较高, 说明谷子根际土壤中含有较多的纤维素及有机质; 在属水平谷子轮作土壤被孢霉菌等腐生菌含量较高, 而连作土壤中亚隔孢壳菌、链格孢霉菌等病原菌增加, 说明谷子轮作根际土壤真菌环境优于谷子连作根际土壤, 连作会导致腐生菌减少, 病原菌增加。但是, 连作5年的谷子根际土壤环境好于连作3年, 说明随连作年限增加, 谷子根际土壤真菌群落有恢复趋势。病原真菌链格孢霉菌、亚隔孢壳菌以及生防菌粉红螺旋聚孢霉菌在连作土壤中相对丰度高, 暗示谷子连作与病害发生有紧密关联, 对克服谷子连作障碍提供了有用的参考依据。
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图 1 不同种植模式谷子根际土壤真菌群落的稀疏曲线
CK: 撂荒地; CR: 谷子-玉米轮作; TC: 谷子连作3年; FC: 谷子连作5年。CK: abandoned land; CR: foxtail millet rotation with maize; TC: continuous cropping for 3 years of foxtail millet; FC: continuous cropping for 5 years of foxtail millet.
Figure 1. Sparse curves of soil fungal community of foxtail millet rhizosphere soils with different cropping patterns
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图 2 不同种植模式谷子根际土壤真菌ITS序列(ASV)分类
A: 不同种植模式真菌ITS序列(ASV)分布Venn图; B: 不同分类级别下不同种植模式ASV数; C: 不同种植模式谷子土壤真菌圈堆积图。CK: 撂荒地; CR: 谷子-玉米轮作; TC: 谷子连作3年; FC: 谷子连作5年。图C中, 在绘制土壤真菌分类等级树图的前提下, 将每个ASV分组的丰度数据以饼图的形式添加到了图中。展示了谷子根际土壤真菌群落分类学构成, 最大的圈代表门水平, 逐渐缩小的圈按照梯度依次代表纲、目、科、属和种, 最内层圆点面积代表ASV的丰度大小, 同时也表示该ASV在各组中的组成比例。A: Venn diagram of fungi ASV (amplicon sequence variants) of different cropping patterns; B: ASV number of different plant patterns at different classification levels; C: taxonomic tree in packed circles of soil fungi classification of foxtail millet under different cropping patterns. CK: abandoned land; CR: foxtail millet rotation with maize; TC: continuous cropping for 3 years of foxtail millet; FC: continuous cropping for 5 years of foxtail millet. For the figure C, on the premise of drawing the tree map of soil fungi classification, the abundance of each ASV group was added to the map in the form of pie chart. The largest circle represents phylum level, and the gradually shrinking circle represents class, order, family, genus and species according to the gradient. The innermost dot area represents the abundance of ASV, and also represents the composition proportion of ASV in each group.
Figure 2. Amplicon sequence variants (ASV) classification of fungi of foxtail millet rhizosphere soil in different planting patterns
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图 3 不同种植模式谷子根际土壤真菌在不同分类水平的相对丰度
A-E表示分类单元在门、纲、目、科和属水平上的百分比。CK: 撂荒地; CR: 谷子-玉米轮作; TC: 谷子连作 3 年; FC: 谷子连 作 5 年。Figure A-E show the percentage of taxa at the phylum, class, order, family, and genus levels. CK: abandoned land; CR: foxtail millet rotation with maize; TC: continuous cropping for 3 years of foxtail millet; FC: continuous cropping for 5 years of foxtail millet.
Figure 3. Relative abundance of fungi in foxtail millet rhizosphere soil under different cropping patterns at different classification levels
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图 4 不同种植模式谷子根际土壤真菌群落的Alpha多样性分析
A: α多样性指数; B: 丰度等级曲线。CK: 撂荒地; CR: 谷子-玉米轮作; TC: 谷子连作3年; FC: 谷子连作5年。A: α diversity index; B: abundance grade curve. CK: abandoned land; CR: foxtail millet rotation with maize; TC: continuous cropping for 3 years of foxtail millet; FC: continuous cropping for 5 years of foxtail millet. ASV: amplicon sequence variants.
Figure 4. Alpha diversity analysis of fungi community of foxtail millet rhizosphere soil under different cropping patterns
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图 5 不同种植模式谷子根际土壤真菌群落β多样性分析
A: PCoA分析; B: 组间差异分析。CK: 撂荒地; CR: 谷子-玉米轮作; TC: 谷子连作3年; FC: 谷子连作5年。A: PCoA analysis; B: analysis of differences among four groups. CK: abandoned land; CR: foxtail millet rotation with maize; TC: continuous cropping for 3 years of foxtail millet; FC: continuous cropping for 5 years of foxtail millet.
Figure 5. β diversity analysis of fungi community of foxtail millet rhizosphere soil under different cropping patterns
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图 6 不同种植模式谷子根际土壤真菌群落冗余分析
CK: 撂荒地; CR: 谷子-玉米轮作; TC: 谷子连作3年; FC: 谷子连作5年。AN: alkaline hydrolysis nitrogen; AK: available potassium; AP: available phosphorus; OM: organic matter; PPO: polyphenol oxidase; CAT: catalase. CK: abandoned land; CR: foxtail millet rotation with maize; TC: continuous cropping for 3 years of foxtail millet; FC: continuous cropping for 5 years of foxtail millet.
Figure 6. Redundancy analysis of fungi community of foxtail millet rhizosphere soil under different cropping patterns
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图 7 不同种植模式谷子根际土壤真菌群落LEfSe分析
由里到外, 依次是门、纲、目、科、属和种水平, 其中实心节点代表在CK、CR、TC和FC中起重要作用的微生物类群, 空心节点表示不起重要作用的物种。CK: 撂荒地; CR: 谷子-玉米轮作; TC: 谷子连作3年; FC: 谷子连作5年。From inside to outside is the gorups at phylum, class, order, family, genus and species levels successively. Solid nodes represent that the microbial groups play an important role in CK, CR, TC and FC, while hollow nodes represent the groups do not play an important role in the four treatments. CK: abandoned land; CR: foxtail millet rotation with maize; TC: continuous cropping for 3 years of foxtail millet; FC: continuous cropping for 5 years of foxtail millet.
Figure 7. LEfSe analysis of fungi community of foxtail millet rhizosphere soil under different cropping patterns
表 1 不同种植模式谷子根际土壤的真菌高通量测序结果
Table 1 High-throughput sequencing results of fungi in foxtail millet rhizosphere soils with different cropping patterns
样本 Sample 去引物 Input 质量过滤 Filtered 去噪 Denoised 拼接 Merged 去嵌合体 Nonchimeric 非单丰度序列 Nonsingleton CK1 84 027 72 625 72 198 71 545 70 622 70 622 CK2 126 381 113 085 112 560 111 845 109 959 109 959 CK3 89 761 78 138 77 541 76 793 75 687 75 687 CR1 191 960 176 283 175 227 174 315 166 205 166 205 CR2 107 110 94 546 93 956 93 200 92 359 92 358 CR3 117 377 102 500 101 873 101 068 98 463 98 463 TC1 137 752 120 634 120 061 119 468 117 184 117 184 TC2 99 344 86 259 85 673 85 041 82 241 82 241 TC3 88 864 78 645 78 247 77 656 77 136 77 136 FC1 116 128 102 142 101 466 100 870 98 526 98 526 FC2 104 460 91 841 91 398 90 841 90 022 90 022 FC3 96 306 84 106 83 632 82 980 82 011 82 011 CK: 撂荒地; CR: 谷子-玉米轮作; TC: 谷子连作3年; FC: 谷子连作5年。各处理缩写后的数据为重复。CK: abandoned land; CR: foxtail millet rotation with maize; TC: continuous cropping for 3 years of foxtail millet; FC: continuous cropping for 5 years of foxtail millet. The data after abbreviation of treatment is the replicate. 
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表 2 谷子根际土壤酶活性与理化性质的相关性分析
Table 2 Correlation analysis between enzyme activity and physicochemical properties of foxtail millet rhizosphere soil
pH 碱解氮
Alkaline hydrolysis
nitrogen有效磷
Available
phosphorus速效钾
Available
potassium有机质
Organic matter多酚氧化酶
Polyphenol oxidase过氧化氢酶
Catalase脲酶
Urease蔗糖酶
SucrasepH 1.000 0.466 0.521 0.303 0.314 −0.291 −0.331 −0.203 −0.616* 碱解氮
Alkaline hydrolysis nitrogen0.466 1.000 0.588* 0.272 0.906** 0.170 0.360 0.628* 0.081 有效磷
Available phosphorus0.521 0.588* 1.000 0.216 0.614* 0.012 0.024 0.281 0.131 速效钾
Available potassium0.303 0.272 0.216 1.000 0.147 0.669* 0.451 0.326 0.230 有机质
Organic matter0.314 0.906** 0.614* 0.147 1.000 0.145 0.367 0.654* 0.175 多酚氧化酶
Polyphenol oxidase−0.291 0.170 0.012 0.669* 0.145 1.000 0.855** 0.681* 0.769** 过氧化氢酶
Catalase−0.331 0.360 0.024 0.451 0.367 0.855** 1.000 0.840** 0.682* 脲酶
Urease−0.203 0.628* 0.281 0.326 0.654* 0.681* 0.840** 1.000 0.691* 蔗糖酶 Sucrase −0.616* 0.081 0.131 0.230 0.175 0.769** 0.682* 0.691* 1.000 * 表示在0.05水平差异显著, ** 表示在0.01水平差异显著。* correlation is significant at the 0.05 level; ** correlation is significant at the 0.01 level.
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表 3 谷子根际土壤真菌群落多样性指数与理化性质、酶活性的相关性分析
Table 3 Correlation analysis of fungi community diversity indexes with physicochemical properties and enzyme activities of foxtail millet rhizosphere soil
Chao1指数
Chao1 indexGood’s coverage指数
Good’s coverage indexObserved species指数
Observed species indexShannon指数
Shannon indexPH −0.339 0.265 −0.316 −0.108 碱解氮 Alkaline hydrolysis nitrogen −0.038 0.369 0.006 0.024 有效磷 Available phosphorus −0.105 0.381 −0.065 −0.076 速效钾 Available potassium 0.505 0.097 0.539 0.227 有机质 Organic matter −0.048 0.389 −0.002 −0.054 多酚氧化酶 Polyphenol oxidase 0.776** −0.398 0.770** 0.038 过氧化氢酶 Catalase 0.633* −0.380 0.625* 0.034 脲酶 Urease 0.348 −0.021 0.363 −0.088 蔗糖酶 Sucrase 0.613* −0.210 0.614* −0.048 *和**分别表示在P<0.05和P<0.01水平显著相关。* and ** mean significant correlation at P<0.05 and P<0.01 levels, respectively.
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[1] MARTIN L, MESSAGER E, BEDIANASHVILI G, et al. The place of millet in food globalization during Late Prehistory as evidenced by new bioarchaeological data from the Caucasus[J]. Scientific Reports, 2021, 11(1): 13124 doi: 10.1038/s41598-021-92392-9
[2] POSPIESZNY Ł, MAKAROWICZ P, LEWIS J, et al. Isotopic evidence of millet consumption in the Middle Bronze Age of East-Central Europe[J]. Journal of Archaeological Science, 2021, 126: 105292 doi: 10.1016/j.jas.2020.105292
[3] DIAO X M. Production and genetic improvement of minor cereals in China[J]. The Crop Journal, 2017, 5(2): 103−114 doi: 10.1016/j.cj.2016.06.004
[4] HOU D Z, CHEN J, REN X, et al. A whole foxtail millet diet reduces blood pressure in subjects with mild hypertension[J]. Journal of Cereal Science, 2018, 84: 13−19 doi: 10.1016/j.jcs.2018.09.003
[5] 李锐, 刘瑜, 褚贵新, 等. 棉花连作对北疆土壤酶活性、致病菌及拮抗菌多样性的影响[J]. 中国生态农业学报, 2015, 23(4): 432−440 LI R, LIU Y, CHU G X, et al. Response of soil enzyme activity and microbial community structure, diversity to continuous cotton cropping in northern Xinjiang[J]. Chinese Journal of Eco-Agriculture, 2015, 23(4): 432−440
[6] XIONG W, LI Z G, LIU H J, et al. The effect of long-term continuous cropping of black pepper on soil bacterial communities as determined by 454 pyrosequencing[J]. PLoS ONE, 2015, 10(8): e0136946 doi: 10.1371/journal.pone.0136946
[7] URASHIMA Y, SONODA T, FUJITA Y, et al. Application of PCR-denaturing-gradient gel electrophoresis (DGGE) method to examine microbial community structure in asparagus fields with growth inhibition due to continuous cropping[J]. Microbes and Environments, 2011, 27: 43−48
[8] ZHOU X G, GAO D M, LIU J, et al. Changes in rhizosphere soil microbial communities in a continuously monocropped cucumber (Cucumis sativus L.) system[J]. European Journal of Soil Biology, 2014, 60: 1−80
[9] LIU W X, WANG Q L, WANG B Z, et al. Changes in the abundance and structure of bacterial communities under long-term fertilization treatments in a peanut monocropping system[J]. Plant and Soil, 2015, 395(1/2): 415−427
[10] QIN S H, YEBOAH S, XU X X, et al. Analysis on fungal diversity in rhizosphere soil of continuous cropping potato subjected to different furrow-ridge mulching managements[J]. Frontiers in Microbiology, 2017, 8: 845
[11] LEI H Y, LIU A K, HOU Q W, et al. Diversity patterns of soil microbial communities in the Sophora flavescens rhizosphere in response to continuous monocropping[J]. BMC Microbiology, 2020, 20(1): 272 doi: 10.1186/s12866-020-01956-8
[12] 侯慧, 董坤, 杨智仙, 等. 连作障碍发生机理研究进展[J]. 土壤, 2016, 48(6): 1068−1076 HOU H, DONG K, YANG Z X, et al. Advance in mechanism of continuous cropping obstacle[J]. Soils, 2016, 48(6): 1068−1076
[13] YING Y X, DING W L, ZHOU Y Q, et al. Influence of panax ginseng continuous cropping on metabolic function of soil microbial communities[J]. Chinese Herbal Medicines, 2012, 4(4): 329−334
[14] 刘建国, 张伟, 李彦斌, 等. 新疆绿洲棉花长期连作对土壤理化性状与土壤酶活性的影响[J]. 中国农业科学, 2009, 42(2): 725−733 doi: 10.3864/j.issn.0578-1752.2009.02.044 LIU J G, ZHANG W, LI Y B, et al. Effects of long-term continuous cropping system of cotton on soil physical-chemical properties and activities of soil enzyme in oasis in Xinjiang[J]. Scientia Agricultura Sinica, 2009, 42(2): 725−733 doi: 10.3864/j.issn.0578-1752.2009.02.044
[15] LI X G, DING C F, HUA K, et al. Soil sickness of peanuts is attributable to modifications in soil microbes induced by peanut root exudates rather than to direct allelopathy[J]. Soil Biology and Biochemistry, 2014, 78: 149−159 doi: 10.1016/j.soilbio.2014.07.019
[16] 张晓玲, 潘振刚, 周晓锋, 等. 自毒作用与连作障碍[J]. 土壤通报, 2007, 38(4): 781−784 doi: 10.3321/j.issn:0564-3945.2007.04.033 ZHANG X L, PAN Z G, ZHOU X F, et al. Autotoxicity and continuous cropping obstacles: A review[J]. Chinese Journal of Soil Science, 2007, 38(4): 781−784 doi: 10.3321/j.issn:0564-3945.2007.04.033
[17] WU Z J, XIE Z K, YANG L, et al. Identification of autotoxins from root exudates of Lanzhou lily (Lilium davidii var unicolor)[J]. Allelopathy Journal, 2015, 35: 35−48
[18] LI X G, DING C F, ZHANG T L, et al. Fungal pathogen accumulation at the expense of plant-beneficial fungi as a consequence of consecutive peanut mono culturing[J]. Soil Biology and Biochemistry, 2014, 72: 11−18 doi: 10.1016/j.soilbio.2014.01.019
[19] LU F G, WANG L, LIU Y N, et al. Analysis of culturable fungal diversity in rhizosphere soil of healthy and diseased cotton in Southern Xinjiang[J]. African Journal of Microbiology Research, 2012, 6: 7357−7364 doi: 10.5897/AJMR12.1146
[20] NAIR A, NGOUAJIO M. Soil microbial biomass, functional microbial diversity, and nematode community structure as affected by cover crops and compost in an organic vegetable production system[J]. Applied Soil Ecology, 2012, 58: 45−55 doi: 10.1016/j.apsoil.2012.03.008
[21] WANG Y, XU J, SHEN J H, et al. Tillage, residue burning and crop rotation alter soil fungal community and water-stable aggregation in arable fields[J]. Soil and Tillage Research, 2010, 107(2): 71−79 doi: 10.1016/j.still.2010.02.008
[22] DE BOER W, FOLMAN L B, SUMMERBELL R C, et al. Living in a fungal world: impact of fungi on soil bacterial niche development[J]. FEMS Microbiology Reviews, 2005, 29(4): 795−811 doi: 10.1016/j.femsre.2004.11.005
[23] SOBEK E, ZAK J. The Soil FungiLog procedure: method and analytical approaches toward understanding fungal functional diversity[J]. Mycologia, 2003, 95: 590−602 doi: 10.1080/15572536.2004.11833063
[24] 李夏, 妙佳源, 高小丽, 等. 连作条件下谷子叶片衰老与活性氧代谢研究[J]. 中国农业大学学报, 2016, 21(4): 1−9 doi: 10.11841/j.issn.1007-4333.2016.04.01 LI X, MIAO J Y, GAO X L, et al. Leaf senescence and reactive oxygen metabolism of millet under continuous cropping[J]. Journal of China Agricultural University, 2016, 21(4): 1−9 doi: 10.11841/j.issn.1007-4333.2016.04.01
[25] 卢成达, 郭志利, 李阳, 等. 长期定点连作及单序轮作处理对旱地谷子的光合特性、根系构型和产量的影响[J]. 农学学报, 2019, 9(5): 10−14 doi: 10.11923/j.issn.2095-4050.cjas18090004 LU C D, GUO Z L, LI Y, et al. Long-term continuous and rotation cropping: effect on photosynthetic characteristics, root configuration and yield of dry-land millet[J]. Journal of Agriculture, 2019, 9(5): 10−14 doi: 10.11923/j.issn.2095-4050.cjas18090004
[26] 妙佳源, 李夏, 周达, 等. 连作对谷子土壤酶活性及养分的影响[J]. 干旱地区农业研究, 2016, 34(3): 123−126, 152 doi: 10.7606/j.issn.1000-7601.2016.03.19 MIAO J Y, LI X, ZHOU D, et al. Effects of foxtail millet continuous cropping on soil enzyme activities and nutrients[J]. Agricultural Research in the Arid Areas, 2016, 34(3): 123−126, 152 doi: 10.7606/j.issn.1000-7601.2016.03.19
[27] DEBENPORT S J, ASSIGBETSE K, BAYALA R, et al. Association of shifting populations in the root zone microbiome of millet with enhanced crop productivity in the Sahel Region (Africa)[J]. Applied and Environmental Microbiology, 2015, 81(8): 2841−2851 doi: 10.1128/AEM.04122-14
[28] DANG K, GONG X W, ZHAO G, et al. Intercropping alters the soil microbial diversity and community to facilitate nitrogen assimilation: a potential mechanism for increasing proso millet grain yield[J]. Frontiers in Microbiology, 2020, 11: 601054 doi: 10.3389/fmicb.2020.601054
[29] 牛倩云, 韩彦莎, 徐丽霞, 等. 作物轮作对谷田土壤理化性质及谷子根际土壤细菌群落的影响[J]. 农业环境科学学报, 2018, 37(12): 2802−2809 doi: 10.11654/jaes.2018-0128 NIU Q Y, HAN Y S, XU L X, et al. Effects of crop rotation on soil physicochemical properties and bacterial community of foxtail millet rhizosphere soil[J]. Journal of Agro-Environment Science, 2018, 37(12): 2802−2809 doi: 10.11654/jaes.2018-0128
[30] 孙倩, 吴宏亮, 陈阜, 等. 不同轮作模式下作物根际土壤养分及真菌群落组成特征[J]. 环境科学, 2020, 41(10): 4682−4689 SUN Q, WU H L, CHEN F, et al. Characteristics of soil nutrients and fungal community composition in crop rhizosphere under different rotation patterns[J]. Environmental Science, 2020, 41(10): 4682−4689
[31] STRICKLAND M S, ROUSK J. Considering fungal: bacterial dominance in soils— Methods, controls, and ecosystem implications[J]. Soil Biology and Biochemistry, 2010, 42(9): 1385−1395 doi: 10.1016/j.soilbio.2010.05.007
[32] LIU R R, XIAO Z Y, HASHEM A, et al. Mycorrhizal fungal diversity and its relationship with soil properties in Camellia oleifera[J]. Agriculture, 2021, 11: 470 doi: 10.3390/agriculture11060470
[33] CALLAHAN B, MCMURDIE P, ROSEN M J, et al. DADA2: High resolution sample inference from Illumina amplicon data[J]. Nature Methods, 2016, 13: 581−583 doi: 10.1038/nmeth.3869
[34] CHAO A. Nonparametric estimation of the number of classes in a population[J]. Scandinavian Journal of Statistics, 1984, 11: 265−270
[35] RAMETTE A. Multivariate analyses in microbial ecology[J]. FEMS Microbiology Ecology, 2007, 62(2): 142−160 doi: 10.1111/j.1574-6941.2007.00375.x
[36] 郝晓芬, 王根全, 郭二虎, 等. 连作、轮作对谷子根际细菌群落结构的影响[J]. 农业环境科学学报, 2022, 41(3): 585−596 doi: 10.11654/jaes.2021-0649 HAO X F, WANG G Q, GUO E H, et al. Effects of continuous cropping and rotation on rhizosphere bacterial community structure of millet[J]. Journal of Agro-Environment Science, 2022, 41(3): 585−596 doi: 10.11654/jaes.2021-0649
[37] KANG S M, KHAN A L, WAQAS M, et al. Plant growth-promoting rhizobacteria reduce adverse effects of salinity and osmotic stress by regulating phytohormones and antioxidants in Cucumis sativus[J]. Journal of Plant Interactions, 2014, 9(1): 673−682 doi: 10.1080/17429145.2014.894587
[38] BANNING N, GLEESON D, GRIGG A, et al. Soil microbial community successional patterns during forest ecosystem restoration[J]. Applied and Environmental Microbiology, 2011, 77: 6158−6164 doi: 10.1128/AEM.00764-11
[39] HARRIS J. Soil microbial communities and restoration ecology: facilitators or followers?[J]. Science, 2009, 325(5940): 573−574 doi: 10.1126/science.1172975
[40] KIM Y C, LEVEAU J, GARDENER B M, et al. The multifactorial basis for plant health promotion by plant-associated bacteria[J]. Applied and Environmental Microbiology, 2011, 77(5): 1548−1555 doi: 10.1128/AEM.01867-10
[41] CAO G F, ZHAO K. Effect of different prevention and control technology combinations of succession cropping obstacle on main diseases of Radix pseudostellariae[J]. Acta Agriculturae Jiangxi, 2013, 25(12): 66−68 doi: 10.19386/j.cnki.jxnyxb.2013.12.017
[42] 保丽美, 丁亚芳, 魏云林, 等. 三七连作与休闲土壤真菌群落组成与多样性分析[J]. 中药材, 2021, 44(1): 7−12 BAO L M, DING Y F, WEI Y L. Analysis on the composition and diversity of fungi community in the continuous cropping and fallow soil ofPanax notoginseng[J]. Journal of Chinese Medicinal Materials, 2021, 44(1): 7−12
[43] ROUSK J, BROOKES P C, BÅÅTH E. Contrasting soil pH effects on fungal and bacterial growth suggest functional redundancy in carbon mineralization[J]. Applied and Environmental Microbiology, 2009, 75(6): 1589−1596 doi: 10.1128/AEM.02775-08
[44] WU H M, QIN X J, WANG J Y, et al. Rhizosphere responses to environmental conditions in Radix pseudostellariae under continuous monoculture regimes[J]. Agriculture, Ecosystems & Environment, 2019, 270/271: 19−31
[45] 孙倩, 吴宏亮, 陈阜, 等. 宁夏中部干旱带不同作物根际土壤真菌群落多样性及群落结构[J]. 微生物学通报, 2019, 46(11): 2963−2972 SUN Q, WU H L, CHEN F, et al. Fungal community diversity and structure in rhizosphere soil of different crops in the arid zone of central Ningxia[J]. Microbiology China, 2019, 46(11): 2963−2972
[46] 王海英, 郭守玉, 黄满荣, 等. 子囊菌较担子菌具有更快的进化速率和更高的物种多样性[J]. 中国科学: 生命科学, 2010, 40(8): 731–737 WANG H Y, GUO S Y, HUANG M R, et al. Ascomycota has faster evolutionary rate and higher species diversity than Basidiomycota (Fungi)[J]. Scientia Sinica Vitae, 2010, 40(8): 731–737
[47] YELLE D J, RALPH J, LU F, et al. Evidence for cleavage of lignin by a brown rot basidiomycete[J]. Environmental Microbiology, 2010, 10(7): 1844−1849 doi: 10.1007/s00203-016-1301-x
[48] WANG Y Z, XU X M, LIU T M, et al. Analysis of bacterial and fungal communities in continuous-cropping ramie (Boehmeria nivea L. Gaud) fields in different areas in China[J]. Scientific Reports, 2020, 10(1): 3264 doi: 10.1038/s41598-020-58608-0
[49] SHANTHIYAA V, SARAVANAKUMAR D, RAJENDRAN L, et al. Use of chaetomium globosum for biocontrol of potato late blight disease[J]. Crop Prot, 2013, 25: 33−38
[50] 宁琪, 陈林, 李芳, 等. 被孢霉对土壤养分有效性和秸秆降解的影响[J]. 土壤学报, 2022, 59(1): 206−217 NING Q, CHEN L, LI F, et al. Effects of Mortierella on nutrient availability and straw decomposition in soil[J]. Acta Pedologica Sinica, 2022, 59(1): 206−217
[51] ZHANG H S, WU X, LI G, et al. Interactions between arbuscular mycorrhizal fungi and phosphate-solubilizing fungus (Mortierella sp.) and their effects on Kostelelzkya virginica growth and enzyme activities of rhizosphere and bulk soils at different salinities[J]. Biology and Fertility of Soils, 2011, 47: 543−554 doi: 10.1007/s00374-011-0563-3
[52] KOECHLI C, CAMPBELL A N, PEPE-RANNEY C, et al. Assessing fungal contributions to cellulose degradation in soil by using high-throughput stable isotope probing[J]. Soil Biology and Biochemistry, 2019, 130: 150−158 doi: 10.1016/j.soilbio.2018.12.013
[53] LIAO X G, FANG W G, LIN L C, et al. Metarhizium robertsii produces an extracellular invertase (MrINV) that plays a pivotal role in rhizospheric interactions and root colonization[J]. PLoS One, 2013, 8(10): e78118 doi: 10.1371/journal.pone.0078118
[54] 代鹏, 陈海琴, 顾震南, 等. 高山被孢霉生产多不饱和脂肪酸发酵条件的研究进展[J]. 食品工业科技, 2014, 35(5): 354−359 DAI P, CHEN H Q, GU Z N, et al. Research progress in fermentation condition for polyunsaturated fatty acids by Mortierella alpina[J]. Science and Technology of Food Industry, 2014, 35(5): 354−359
[55] 沈钰森, 王建升, 盛小光, 等. 十字花科植物黑斑病的研究进展[J]. 核农学报, 2021, 35(3): 623−634 doi: 10.11869/j.issn.100-8551.2021.03.0623 SHEN Y S, WANG J S, SHENG X G, et al. Research progress on black spot in cruciferous plants[J]. Journal of Nuclear Agricultural Sciences, 2021, 35(3): 623−634 doi: 10.11869/j.issn.100-8551.2021.03.0623
[56] 康子腾, 姜黎明, 罗义勇, 等. 植物病原链格孢属真菌的致病机制研究进展[J]. 生命科学, 2013, 25(9): 908−914 KANG Z T, JIANG L M, LUO Y Y, et al. The research advances of mechanism of pathogenicity of Alternaria phytopathogenic fungi[J]. Chinese Bulletin of Life Sciences, 2013, 25(9): 908−914
[57] 吴海霞, 袁梦蕾, 江娜, 等. 粉红螺旋聚孢霉高效生防菌株的筛选与评价[J]. 植物保护, 2021, 47(3): 54−60, 95 WU H X, YUAN M L, JIANG N, et al. Screening and evaluation of highly efficient biocontrol strains of Clonostachys rosea[J]. Plant Protection, 2021, 47(3): 54−60, 95
[58] 刘硕, 郑金柱, 张兆霞, 等. 粉红螺旋聚孢霉对两种林果枝干病原菌的生防作用研究[J]. 山东农业大学学报(自然科学版), 2019, 50(1): 49−51 LIU S, ZHENG J Z, ZHANG Z X, et al. Biocontrol activity of Clonostachys rosea against fungal pathogens of forest and fruit trees Botryosphaeria dothidea and Valsa mali[J]. Journal of Shandong Agricultural University (Natural Science Edition), 2019, 50(1): 49−51
[59] GONG C, LIU Y, LIU S Y, et al. Analysis of Clonostachys rosea-induced resistance to grey mould disease and identification of the key proteins induced in tomato fruit[J]. Postharvest Biology and Technology, 2017, 123: 83−93 doi: 10.1016/j.postharvbio.2016.08.004
[60] BORGES Á V, SARAIVA R M, MAFFIA L A. Biocontrol of gray mold in tomato plants by Clonostachys rosea[J]. Tropical Plant Pathology, 2015, 40(2): 71−76 doi: 10.1007/s40858-015-0010-3
[61] LIU Z X, LIU J J, YU Z H, et al. Long-term continuous cropping of soybean is comparable to crop rotation in mediating microbial abundance, diversity and community composition[J]. Soil and Tillage Research, 2020, 197: 104503 doi: 10.1016/j.still.2019.104503
[62] 李春格, 李晓鸣, 王敬国. 大豆连作对土体和根际微生物群落功能的影响[J]. 生态学报, 2006, 26(4): 1144−1150 LI C G, LI X M, WANG J G. Effect of soybean continuous cropping on bulk and rhizosphere soil microbial community function[J]. Acta Ecologica Sinica, 2006, 26(4): 1144−1150
[63] 王娟英, 许佳慧, 吴林坤, 等. 不同连作年限怀牛膝根际土壤理化性质及微生物多样性[J]. 生态学报, 2017, 37(17): 5621−5629 WANG J Y, XU J H, WU L K, et al. Analysis of physicochemical properties and microbial diversity in rhizosphere soil of Achyranthes bidentata under different cropping years[J]. Acta Ecologica Sinica, 2017, 37(17): 5621−5629
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