Bacterial community structure and functional potential of rhizosphere soils as influenced by nitrogen addition and bacterial wilt disease under continuous sesame cropping

Abstract BackgroundRalstonia solanacearum is one of the most notorious soil-born phytopathogen that causes a severe wilt disease with deadly effects on many economically important crops. The microbial community structure and interactions are commonly changed between bacterial wilt susceptible soil and healthy soil. Here, the bacterial community structure, correlation analysis with soil chemical properties, interaction network of healthy soil (HS, nearly no disease happened at recent three years) and diseased soil (DS, suffered heavy bacterial wilt disease) were analyzed.ResultsCompared to DS, a higher bacterial community diversity index was found in HS, and the relative abundance of main genera Bacillus, Gaiellales, Roseiflexus, Gemmatimonadaceae, Nocardioides and Anaerolineacear reached significant level. Redundancy analysis on genus level indicated that rapid available phosphate played key role on bacterial community distribution difference, and showed negative correlation with the other four chemical properties. Interaction network analysis further demonstrated that the higher genus community diversity and more extensive interactions were existed in HS network and formed stable network, and the genera Mycobacterium, Cyanobacteria and Rhodobiaceae should be the key components that sustain the network stably. Seven clusters of orthologous groups reached significant level difference between HS and DS. Moreover, 55 bacterial strains with distinct antagonistic activities to R. solancearum were isolated and identified. ConclusionsIn summary, our findings indicate that the bacterial diversity and interaction network changed between the HS and DS samples, which are also provide a good research basis for future biological control to the bacterial wilt.

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Bacterial community structure and functional potential in the northeastern Chukchi Sea

Continental Shelf Research ◽

10.1016/j.csr.2017.01.018 ◽

2017 ◽

Vol 136 ◽

pp. 20-28 ◽

Cited By ~ 7

Author(s):

Kelly M. McFarlin ◽

Jennifer M. Questel ◽

Russell R. Hopcroft ◽

Mary Beth Leigh

Keyword(s):

Community Structure ◽

Bacterial Community ◽

Bacterial Community Structure ◽

Chukchi Sea ◽

Functional Potential

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Rhizobacterial community structure in grafted tomato plants infected by Ralstonia solanacearum

Biodiversitas Journal of Biological Diversity ◽

10.13057/biodiv/d211055 ◽

2020 ◽

Vol 21 (10) ◽

Author(s):

Lisa Navitasari ◽

TRI JOKO ◽

RUDI HARI MURTI ◽

TRIWIDODO ARWIYANTO

Keyword(s):

Community Structure ◽

Bacterial Wilt ◽

Ralstonia Solanacearum ◽

Wilt Disease ◽

16S Rrna Genes ◽

Rrna Genes ◽

Distinct Region ◽

Tomato Plants ◽

Bacterial Wilt Disease ◽

Significant Difference

Abstract. Navitasari L, Joko T, Murti RH, Arwiyanto T. 2020. Rhizobacterial community structure in grafted tomato plants infected by Ralstonia solanacearum. Biodiversitas 21: 4888-4895. Bacterial wilt disease caused by Ralstonia solanacearum is a devastating soil-borne vascular disease of tomato leading to a 100% yield loss. One of the alternatives to suppress the infestation of R. solanacearum infestation is the application of grafting techniques, which has been studied and successfully practiced by tomato growers. However, the infestation mode of R. solanacearum and the rhizobacterial community structure in grafted tomato plants are poorly reported. In this study, the rhizobacterial community structure in grafted tomato plants infected by R. solanacearum was investigated. The experiment was conducted on tomato germplasms with the implementation of tube grafting using resistant rootstocks (Amelia from Indonesia, H.7996 from Asian Vegetable Research Development Center/AVRDC) and susceptible scion (Servo from Indonesia). The rhizobacterial community structure was analyzed by metagenomic study under 16S rRNA genes sequencing with a distinct region (16SV3-V4) that was amplified using a specific primer (16SV4: 515F-806R) 5’-GTGCCAGCMGCCGCGGTAA and 5’GGACTACHVHHHTWTCTAAT. The results indicated that the grafted tomato plants and resistant rootstocks that were infected by R. solanacearum showed significantly lower intensity of bacterial wilt disease compared to the susceptible scion. The rhizobacterial community structure in the grafted tomato plants infected by R. solanacearum was indicated by predominant phyla of Proteobacteria, Firmicutes, and Actinobacteria with dominant genera of Pseudomonas and Bacillus. Besides, significant difference was also indicated by species of Geitlerinema sp. in the grafted tomatoes infected by R. solanacearum.

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Comprehensive Effect of Salt Stress and Peanut Cultivars on the Bacterial Community Structure and Diversity of Peanut Rhizosphere Soils

10.21203/rs.3.rs-55891/v1 ◽

2020 ◽

Author(s):

Yang Xu ◽

Hong Ding ◽

Saiqun Wen ◽

Dunwei Ci ◽

Guanchu Zhang ◽

...

Keyword(s):

Salt Stress ◽

Community Structure ◽

Salt Tolerance ◽

Bacterial Community ◽

Stress Tolerance ◽

Bacterial Community Structure ◽

Rrna Gene ◽

Rhizosphere Soils ◽

Rhizosphere Bacterial Community ◽

Peanut Cultivars

Abstract Background: Plant rhizosphere bacterial communities influence plant growth and stress tolerance, which differs across cultivars and external environments. Peanut (Arachis hypogaea. L) as an important oil crop cultivated worldwide. However, relatively little is known about the comprehensive effects of environmental conditions and peanut cultivars on rhizosphere bacterial community structure and diversity. Results: Here, bacterial community structure diversity from rhizosphere soils of various susceptible and resistant peanut cultivars with or without salt stress was analyzed by 16S rRNA gene deep sequencing and quantitative PCR assays. Taxonomic analysis showed that the bacterial community predominantly consisted of phyla Actinobacteria, Proteobacteria, Chloroflexi, Acidobacteria, and Cyanobacteria. Among these bacteria, numbers of beneficial bacteria Cyanobacteria and Proteobacteria increased, while that of Acidobacteria decreased after salt treatment. Metabolic function prediction showed that the percentages of reads categorized to signaling transduction and inorganic ion transport and metabolism were higher in the salt-treated soils, which may be beneficial to plant survival and salt tolerance. Conclusions: Overall, rhizosphere bacterial community structure and population metabolism are affected by salt stress, which may be conducive to peanut stress tolerance in saline-alkali soil. The study is therefore crucially important to develop the foundation for improving the salt tolerance of peanuts via modifying the soil bacterial community.

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Bacterial community diversity associated with the severity of bacterial wilt disease in tomato fields in southeast China

Canadian Journal of Microbiology ◽

10.1139/cjm-2018-0637 ◽

2019 ◽

Vol 65 (7) ◽

pp. 538-549

Author(s):

Xuefang Zheng ◽

Bo Liu ◽

Yujing Zhu ◽

Jieping Wang ◽

Haifeng Zhang ◽

...

Keyword(s):

Soil Ph ◽

Bacterial Wilt ◽

Ralstonia Solanacearum ◽

Wilt Disease ◽

Community Diversity ◽

Healthy Plant ◽

Diseased Plant ◽

Exchangeable Calcium ◽

Rhizosphere Soils ◽

Bacterial Wilt Disease

Tomato bacterial wilt caused by Ralstonia solanacearum is a devastating plant disease. The aims of this study were to investigate the relationship among soil nutrients, rhizobacterial community, and abundance of R. solanacearum, and to gather useful information for controlling the disease. Fifteen tomato rhizosphere soils were collected from three regions, encompassing five disease grades. Then, soil physicochemical properties and rhizobacterial communities were investigated. The content of soil organic carbon (SOC), total phosphorus (TP), total potassium (TK), and exchangeable calcium was significantly higher in the healthy plant rhizosphere soils than in diseased plant rhizosphere soils (P < 0.05). The healthy soils had a relatively higher abundance of Proteobacteria and a lower abundance of Acidobacteria than the diseased soils from the same region. Redundancy analysis demonstrated that R. solanacearum abundance was positively correlated with total nitrogen content and negatively correlated with soil pH, SOC, TP, TK, and exchangeable calcium. Ralstonia solanacearum abundance correlated positively with Chloroflexi, Acidobacteria, and Planctomycetes abundance but negatively with Nitrospirae, Bacteroidetes, and Proteobacteria abundance. These results suggested that improving soil pH, applying the amount of P and K fertilizers, and controlling the dosage of N fertilizer might be an effective approach in controlling bacterial wilt disease.

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