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作物学报 ›› 2021, Vol. 47 ›› Issue (8): 1581-1592.doi: 10.3724/SP.J.1006.2021.04160

• 耕作栽培·生理生化 • 上一篇    下一篇

花生根际土壤细菌群落多样性对盐胁迫的响应

戴良香1(), 徐扬1, 张冠初1, 史晓龙2, 秦斐斐1, 丁红1,*(), 张智猛1,*()   

  1. 1山东省花生研究所, 山东青岛 266100
    2沈阳农业大学农学院, 辽宁沈阳 110866
  • 收稿日期:2020-07-17 接受日期:2021-01-13 出版日期:2021-08-12 网络出版日期:2021-02-18
  • 通讯作者: 丁红,张智猛
  • 作者简介:戴良香, E-mail: liangxiangd@163.com
  • 基金资助:
    国家自然科学基金项目(31971856);国家自然科学基金项目(31971854);国家自然科学基金项目(31901574);山东省现代农业产业技术体系创新团队(花生)项目(SDAIT-04-06);山东省农业科学院创新工程项目(CXGC2018B05)

Response of rhizosphere bacterial community diversity to salt stress in peanut

DAI Liang-Xiang1(), XU Yang1, ZHANG Guan-Chu1, SHI Xiao-Long2, QIN Fei-Fei1, DING Hong1,*(), ZHANG Zhi-Meng1,*()   

  1. 1Shandong Peanut Research Institute, Qingdao 266100, Shandong, China
    2College of Agronomy, Shenyang Agricultural University, Shenyang 110866, Liaoning, China
  • Received:2020-07-17 Accepted:2021-01-13 Published:2021-08-12 Published online:2021-02-18
  • Contact: DING Hong,ZHANG Zhi-Meng
  • Supported by:
    National Natural Science Foundation of China(31971856);National Natural Science Foundation of China(31971854);National Natural Science Foundation of China(31901574);Modern Agricultural Industry Technical System of Shandong Province(SDAIT-04-06);Agricultural Scientific and Technological Innovation Project of Shandong Academy of Agricultural Sciences(CXGC2018B05)

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摘要：

为明确盐胁迫条件下花生根际土壤细菌群落结构的变化, 采用盆栽试验设置不同盐胁迫强度处理, 以开花下针期和成熟期花生根际土壤为研究对象, 提取其总DNA并构建细菌16S rRNA基因文库, 利用高通量测序技术进行测序, 并对测序结果进行生物信息学分析。结果显示, 各处理样本根际土壤优势菌门均为变形菌门(Proteobacteria)、放线菌门(Actinobacteria)、Patescibacteria、酸杆菌门(Acidobacteria)、绿弯菌门(Chloroflexi)。优势菌目分别为(Saccharimonadales)、β-变形菌目(Betaproteobacteria)、鞘脂单胞菌目(sphingomonadales)、芽单胞菌目(Gemmatimonadales)和根瘤菌目(Rhizobiales)。盐胁迫提高了变形菌门(Proteobacteria)的相对丰度, 但降低了放线菌门(Actinobacteria)的相对丰度, 且均随盐胁迫强度提高其升降幅度增大。盐胁迫下基施钙肥使β-变形菌目(Betaproteobacteria)、芽单胞菌目(Gemmatimonadales)和鞘脂单胞菌目(Sphingomonadales)相对丰度显著升高, 并均受盐胁迫强度、生育时期和外源施钙肥的影响。聚类分析结果表明, 较高浓度盐胁迫处理样本的优势菌属组成相似而聚为一组, 非盐胁迫处理样本属水平丰度依生育时期相同而相近, 各聚为一组。盐胁迫强度、生育时期对花生根际土壤微生物菌群类型影响较大, 基施钙肥影响较小。土壤微生物功能预测分析显示, 高盐胁迫可明显降低次生代谢产物、聚糖的生物合成与代谢, 以及氨基酸和脂肪酸代谢等功能基因在根际土壤中的富集。花生旺盛生长期、低盐胁迫和基施钙肥处理使得功能基因丰度大幅提高, 可能对花生生长及胁迫应答具有重要功能。根际土壤微生物菌群多样性的研究将为通过改良土壤微生物环境来提高植物胁迫耐受性提供重要途径。

关键词: 花生, 盐胁迫, 根际, 土壤微生物群落, 16S rRNA基因

Abstract:

To characterize the peanut rhizosphere bacteria community in response to salt stress, a pot experiment was performed with different salt concentrations. The peanut rhizosphere soils at flowering and mature stages were sampled to extract DNA for constructing bacterial 16S rRNA gene library, and then high-throughput sequencing was performed for sequencing and bioinformatics analysis. The results showed that Proteobacteria, Actinobacteria, Patescibacteria, Acidobacteria, and Chloroflexi were the dominant phyla, and the orders Saccharimonadales, Betaproteobacteria, Sphingomonadales, Gemmatimonadales, and Rhizobiales were dominated in the peanut rhizosphere soils. Comparisons of the bacterial community structure of peanuts revealed that the relative abundance of Proteobacteria dramatically increased, while that of Actinobacteria decreased in salt-treated soils, and the fluctuation increased with the increase of the salt concentration. Moreover, applying calcium fertilizer under salt stress increased the abundance of Betaproteobacteria, Gemmatimonadales, and Sphingomonadales, which were affected by salt stress, growth stages, and exogenous calcium application. Cluster analysis revealed that the dominant bacteria of soil groups with high salt concentration were similar and clustered together, while the soil samples of the same growth period were similar and clustered together according to the bacterial structure at the genus level under non-salt stress conditions. Bacterial community structure differed in the growth stages and soil salt concentrations, whereas the differences of soil groups with or without calcium application were relatively small. Function prediction analysis indicated that the sequences related to secondary metabolites, glycan biosynthesis and metabolism, and amino acid and lipid metabolism were enriched in high salt-treated soils. The functional groups increased significantly during the fast-growth period, low salt stress, and basal calcium fertilizer treatments, which may play an important role on the growth and stress response in peanut. This study of microbial communities could lay the foundation for future improvement of stress tolerance of peanuts via modification of the soil microbes.

Key words: peanut (Arachis hypogaea), salt stress, rhizosphere, soil microbial community, 16S rRNA gene

表1

施钙对盐胁迫下花生产量及构成因素的影响"

处理
Treatment		 出米率
Kernel rate to pod (%)		 百果质量
100-pod mass (g)		 百仁质量
100-kernel mass (g)		 产量
Yield (kg hm-2)
CK-HCK 64.70 a 164.67 b 88.78 a 5681.1 b
CY0-HCY0 65.42 a 180.19 a 89.59 a 7189.5 a
CY1-HCY1 65.52 a 143.36 c 72.88 b 3870.6 c
CY2-HCY2 61.15 b 100.95 d 53.09 c 2904.6 d

表2

花生根际微生物群落测序质量"

处理
Treatment		 有效序列数目Seq_num 碱基数
Base_num		 样本序列平均长度
Mean_length		 最短序列长度Min_length 最长序列长度Max_length
CK 118,642.0 52,865,549 445.7210 222.00 482.00
CY0 174,409.0 78,663,396 451.0489 219.00 482.00
CY1 157,500.0 71,203,933 452.0910 201.50 482.00
CY2 168,392.0 75,848,924 450.3773 138.00 482.00
HCK 133,998.0 60,111,521 448.5154 200.00 482.00
HCY0 154,447.5 69,251,925 448.3878 182.00 482.00
HCY1 152,938.5 68,605,609 448.5900 215.50 482.00
HCY2 127,455.5 57,443,681 450.6802 190.50 482.00

图1

不同处理花生土壤样本中OTU数量维恩图 处理同表1。"

图2

Rarefaction曲线 处理同表1。"

表3

各处理根际土壤样本Alpha多样性指数"

处理
Treatment		 丰富度指数
Richness index		 测序深度指数
Sequencing depth		 多样性指数
Diversity index
ACE chao coverage Shannon Simpson sobs
CK 3448.5655 3522.3969 0.9894 6.9797 0.002,170 3113.00
CY0 3661.0442 3715.9220 0.9943 7.1144 0.001,946 3428.50
CY1 3599.9666 3662.6245 0.9955 6.9930 0.002,021 3358.00
CY2 3684.9950 3762.5793 0.9930 6.9466 0.002,337 3364.00
HCK 3548.6551 3594.1464 0.9895 6.5863 0.005,682 3170.50
HCY0 3581.6755 3618.1750 0.9924 6.5738 0.005,456 3246.50
HCY1 3658.1430 3695.8227 0.9917 6.8209 0.003,160 3305.00
HCY2 3562.4287 3633.2745 0.9890 6.9478 0.002,281 3182.50

图3

各样本在门水平的菌落结构及优势菌群组间差异分析 处理同表1。*、**、***分别表示处理间达0.05、0.01和0.001显著性水平。"

图4

各样本在目水平的菌落结构及优势菌群组间差异分析 处理同表1。*、**、***分别表示处理间达0.05、0.01和0.001显著性水平。"

图5

各样本属水平菌落丰度和heatmap图 处理同表1。"

图6

Beta多样性分析 处理同表1。"

图7

土壤微生物菌群功能预测 处理同表1。"

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