Promoting Effects and Mechanism of Bacillus velezensis WB on Watermelon (Citrullus lanatus) Plants
CHEN Zhong-Nan1,2,3, WANG Zhi-Gang1,2,3, XU Wei-Hui1,2,3,*
1 College of Life Science and Agroforestry, Qiqihar University, Qiqihar 161006, China; 2 Heilongjiang Provincial Technology Innovation Center of Agromicrobial Preparation Industrialization, Qiqihar 161006, China; 3 Heilongjiang Provincial Collaborative Innovation Center of Agrobiological Preparation Industrialization, Qiqihar 161006, China
Abstract：Watermelon (Citrullus lanatus) is one of the most popular fruits. With people's continuous pursuit of quality of life, improving products quality has become a key factor in high sales of crops. Plant growth promoting rhizobacteria are a group of beneficial bacteria that promote plant uptake of nutrients from the soil and improve plant health. To investigate the growth promoting effect of Bacillus velezensis WB on watermelon plants. Strain WB and watermelon seeds were selected as materials, the growth promoting ability of strain WB was analyzed using functional culture medium, the growth promoting effect of strain WB was validated using seed germination experiments and pot experiments, and the growth promoting mechanism of strain WB was explored using RNA sequencing (RNA-seq). The results showed that B. velezensis WB had the ability to produce auxin (IAA) and cellulase, as well as the ability to solubilize phosphorus, potassium, and to fixate nitrogen. The results of seed germination and pot experiments indicated that strain WB had a promoting effect on the growth of watermelon plants. In addition, strain WB upregulated the expression of genes related to plant growth promoting signaling pathways, including sesquiterpenoid and triterpenoid biosynthesis,phenylpropanoid biosynthesis, and plant hormone signal transduction pathway. Transcription factors were expressed in promoting growth, such as myoptosis (MYB), NAC (NAM, ATAF and CUC), and Dof (DNA binding with one finger). In conclusion, this study found that B. velezensis WB could promote the growth of watermelon and elucidated its growth promoting mechanisms, and providing theoretical basis for its application in future.
[1] 方澜, 黎妍妍, 江健伟, 等. 2023. 盘龙参内生真菌胞内细菌7-2H的分离鉴定和促生特性研究[J]. 生物技术通报, 39(8): 272-282. (Fang L, Li Y Y, Jiang J W, et al.2023. Isolation, identification and growth-promoting characteristics of endohyphal bacterium 7-2H from endophytic fungi of Spiranthes sinensis[J]. Biotechnology Bulletin, 39(8): 272-282.) [2] 姜晓宇, 高菊生, 徐凤花, 等. 2013. 水稻种子内生细菌多样性及其分泌植物生长素能力的测定[J]. 微生物学报, 53(03): 269-275. (Jiang X Y, Gao J S, Xu F H, et al.2013. Diversity of endophytic bacteria in rice seeds and their secretion of indole acetic acid[J]. Acta Microbiologica Sinica, 53(3): 269-275.) [3] 林英, 司春灿, 黄莉萍, 等. 2019. 香樟根际促生菌的筛选与促生特性研究[J]. 北方园艺, 427(04): 59-64. (Li Y, Si C C, Huang L P, et al.2019. Isolation and promoting characteristics of the rhizospheric bacteria of Cinnamomum camphora[J]. Northern Horticulture, 427(04): 59-64. [4] Abbasi S, Safaie N, Sadeghi A, et al.2019. Streptomyces strains induce resistance to Fusarium oxysporum f. sp. lycopersici race 3 in tomato through different molecular mechanisms[J]. Frontiers in Microbiology, 10: 1505. [5] Ali A M, Awad M Y M, Hegab S A, et al.2021. Effect of potassium solubilizing bacteria (Bacillus cereus) on growth and yield of potato[J]. Journal of Plant Nutrition, 44(3): 411-420. [6] Balla A, Silini A, Cherif-Silini H, et al.2022. Screening of cellulolytic bacteria from various ecosystems and their cellulases production under multi-stress conditions[J]. Catalysts, 12(7): 769. [7] Benbrik B, Elabed A, Iraqui M, et al.2021. A phosphocompost amendment enriched with PGPR consortium enhancing plants growth in deficient soil[J]. Communications in Soil Science and Plant Analysis, 52(11): 1236-1247. [8] Cao Y, Li K, Li Y, et al.2020. MYB Transcription factors as regulators of secondary metabolism in plants[J]. Biology, 9(3): 61. [9] Chen Z, Wang Z, Xu W.2023. Bacillus velezensis WB induces systemic resistance in watermelon against Fusarium wilt[J]. Pest Management Science, 80(3): 1423-1434. [10] Dai L, Zhang G, Yu Z, et al.2019. Effect of drought stress and developmental stages on microbial community structure and diversity in peanut rhizosphere soil[J]. International Journal of Medical Sciences, 20(9): 2265. [11] Diao P, Chen C, Zhang Y, et al.2020. The role of NAC transcription factor in plant cold response[J]. Plant Signaling & Behavior, 15(9): 1785668. [12] Durairaj J, Thankappan S, Prabina B J, et al.2022. Rhizosphere engineering of rice with plant growth promoting rhizobacteria (PGPR) elicits crop growth and soil microcosm in blue-r dye contaminated soil[J]. Communications in Soil Science and Plant Analysis, 53(18): 2434-2446. [13] Egamberdiyeva D, Höflich G.2004. Effect of plant growth-promoting bacteria on growth and nutrient uptake of cotton and pea in a semi-arid region of Uzbekistan[J]. Journal of Arid Environments, 56(2): 293-301. [14] Geng G, Li R, Stevanato P, et al.2020. Physiological and transcriptome analysis of sugar beet reveals different mechanisms of response to neutral salt and alkaline salt stresses[J]. Frontiers in Plant Science, 11: 571846. [15] Goswami M, Deka S.2020. Isolation of a novel rhizobacteria having multiple plant growth promoting traits and antifungal activity against certain phytopathogens[J]. Microbiological Research, 240: 126516. [16] Huang J, Wang S, Wang X, et al.2020. Structure and expression analysis of seven salt-related ERF genes of populus[J]. PeerJ, 8: e10206. [17] Javed Z, Tripathi G D, Mishra M, et al.2021. Actinomycetes-The microbial machinery for the organic-cycling, plant growth, and sustainable soil health[J]. Biocatalysis and Agricultural Biotechnology, 31: 101893. [18] Kim D, Paggi J M, Park C, et al.2019. Graph-based genome alignment and genotyping with HISAT2 and HISAT-genotype[J]. Nature Biotechnology, 37(8): 907-915. [19] Kousar B, Bano A, Khan N.2020. PGPR Modulation of secondary metabolites in tomato infested with Spodoptera litura[J]. Agronomy Journal, 10(6): 778. [20] Lee H G, Park B Y, Kim H U, et al.2015. MYB96 stimulates C18 fatty acid elongation in Arabidopsis seeds[J]. Plant Biotechnology Reports, 9(3): 161-166. [21] Li C, Xu M, Cai X, et al.2022. Jasmonate signaling pathway modulates plant defense, growth, and their trade-offs[J]. International Journal of Medical Sciences, 23(7): 3945. [22] Lim J H, Ahn C H, Jeong H Y, et al.2011. Genetic monitoring of multi-functional plant growth promoting rhizobacteria Bacillus subtilis AH18 and Bacillus licheniformis K11 by multiplex and real-time polymerase chain reaction in a pepper farming field[J]. Journal of the Korean Society for Applied Biological Chemistry, 54(2): 221-228. [23] Liu H, Wang Z, Xu W, et al.2020. Bacillus pumilus LZP02 promotes rice root growth by improving carbohydrate metabolism and phenylpropanoid biosynthesis[J]. Molecular Plant-Microbe Interactions®, 33(10): 1222-1231. [24] Liu Y, Chen L, Zhang N, et al.2016. Plant-microbe communication enhances auxin biosynthesis by a root-associated bacterium, Bacillus amyloliquefaciens SQR9[J]. Molecular Plant-Microbe Interactions®, 29(4): 324-330. [25] Livak K J, Schmittgen T D.2001. Analysis of relative gene expression data using real-time quantitative PCR and the 2-ΔΔCT method[J]. Methods, 25(4): 402-408. [26] Love M I, Huber W, Anders S.2014. Moderated estimation of fold change and dispersion for RNA-seq data with DEseq2[J]. Genome Biology, 15(12): 550. [27] Marini F, Linke J, Binder H.2020. Ideal: An R/Bioconductor package for interactive differential expression analysis[J]. BMC Bioinformatics, 21(1): 565. [28] Mariutto M, Duby F, Adam A, et al.2011. The elicitation of a systemic resistance by Pseudomonas putida BTP1 in tomato involves the stimulation of two lipoxygenase isoforms[J]. BMC Plant Biology, 11(1): 29. [29] Mokale K A L, Chio C, Khatiwada J R, et al.2022. Characterization of cellulose-degrading bacteria isolated from soil and the optimization of their culture conditions for cellulase production[J]. Applied Biochemistry and Biotechnology, 194(11): 5060-5082. [30] Sharma C K, Vishnoi V K, Dubey R C, et al.2018. A twin rhizospheric bacterial consortium induces systemic resistance to a phytopathogen Macrophomina phaseolina in mung bean[J]. Rhizosphere, 5: 71-75. [31] Shen H, He X, Liu Y, et al.2016. A complex inoculant of N2-fixing, P-and K-solubilizing bacteria from a purple soil improves the growth of kiwifruit (Actinidia chinensis) plantlets[J]. Frontiers in Microbiology, 7: 841. [32] Souii A, Guesmi A, Ouertani R, et al.2018. Carboxymethyl cellulase production by extremotolerant bacteria in low-cost media and application in enzymatic saccharification of stevia biomass[J]. Waste and Biomass Valorization, 11(5): 2111-2122. [33] Stoll A, Salvatierra-Martínez R, González M, et al.2021. Importance of crop phenological stages for the efficient use of PGPR inoculants[J]. Scientific Reports, 11(1): 19548. [34] Su L, Wan S, Zhou J, et al.2021. Transcriptional regulation of plant seed development[J]. Physiologia Plantarum, 173(4): 2013-2025. [35] Wagi S, Ahmed A.2019. Bacillus spp.: Potent microfactories of bacterial IAA[J]. PeerJ, 7: e7258. [36] Wang G, Wang X, Zhang Y, et al.2021. Dynamic characteristics and functional analysis provide new insights into long non-coding RNA responsive to Verticillium dahliae infection in Gossypium hirsutum[J]. BMC Plant Biology, 21(1): 68. [37] Wang K, Wang Z, Xu W.2022. Induced oxidative equilibrium damage and reduced toxin synthesis in Fusarium oxysporum f. sp. niveum by secondary metabolites from Bacillus velezensis WB[J]. FEMS Microbiology Ecology, 98(8): 80. [38] Wei S, Chen Y, Hou J, et al.2021. Aux/IAA and ARF gene families in salix suchowensis: Identification, evolution, and dynamic transcriptome profiling during the plant growth process[J]. Frontiers in Plant Science, 12: 666310. [39] Wu J, Mao X, Cai T, et al.2006. KOBAS server: A web-based platform for automated annotation and pathway identification[J]. Nucleic Acids Research, 34(2): W720-W724. [40] Xiao AW, Li Z, Li W C, et al.2020. The effect of plant growth-promoting rhizobacteria (PGPR) on arsenic accumulation and the growth of rice plants (Oryza sativa L.)[J]. Chemosphere, 242: 125136. [41] Xu W, Wang K, Wang H, et al.2020. Evaluation of the biocontrol potential of Bacillus sp. WB against Fusarium oxysporum f. sp. niveum[J]. Biological Control, 147: 104288. [42] Yadegari M, Rahmani H A, Noormohammadi G, et al.2010. Plant growth promoting rhizobacteria increase growth, yield and nitrogen fixation in Phaseolus vulgaris[J]. Journal of Plant Nutrition, 33(12): 1733-1743. [43] Yuan Z, Zhao Y, Mo Z, et al.2022. A Bacillus licheniformis glycoside hydrolase 43 protein is recognized as a MAMP[J]. International Journal of Medical Sciences, 23(22): 14435. [44] Zhu Q, Gao P, Liu S, et al.2017. Comparative transcriptome analysis of two contrasting watermelon genotypes during fruit development and ripening[J]. BMC Genomics, 18(1): 3. [45] Zou J, Deng F, Wang M, et al.2022. scCODE: an R package for data-specific differentially expressed gene detection on single-cell RNA-sequencing data[J]. Briefings in Bioinformatics, 23(5): 180.
