Effects of two Bacillus velezensis strains isolated from different sources on the growth of Capsicum annum

Bao Wang; Shimeng Tan; Mingde Wu; Yujie Feng; Wanrong Yan; Qian Yun; Xuncong Ji; Runmao Lin; Zhixiang Zhao

doi:10.3389/fmicb.2024.1504660

Effects of two Bacillus velezensis strains isolated from different sources on the growth of Capsicum annum

Front Microbiol. 2024 Dec 9:15:1504660. doi: 10.3389/fmicb.2024.1504660. eCollection 2024.

Authors

Bao Wang^{1

2

3}, Shimeng Tan¹, Mingde Wu⁴, Yujie Feng¹, Wanrong Yan¹, Qian Yun¹, Xuncong Ji¹, Runmao Lin², Zhixiang Zhao¹

Affiliations

¹ Key Laboratory of Plant Disease and Pest Control of Hainan Province, Institute of Plant Protection Academy of Agricultural Sciences (Research Center of Quality Safety and Standards for Agricultural Products of Hainan Academy of Agricultural Sciences), Haikou, China.
² Key Laboratory of Green Prevention and Control of Tropical Plant Diseases and Pests, Ministry of Education, School of Tropical Agriculture and Forestry, School of Breeding and Multiplication (Sanya Institute of Breeding and Multiplication), Hainan University, Haikou and Sanya, China.
³ School of Life and Health Science, Hainan University, Haikou, China.
⁴ Key Laboratory of Plant Pathology of Hubei Province, Huazhong Agricultural University, Wuhan, China.

Abstract

Microbial inoculants offer an environmentally friendly approach to enhance plant growth and control disease. In this study, two Bacillus velezensis strains, HKSSLJEBR3 (R3) and Ya-1 were isolated from pepper plant roots and tropical rainforest soil, respectively. Both strains exhibited strong antifungal activity against Fusarium oxysporum f. sp. capsici, with inhibition rates of 48.54 ± 0.66% for R3 and 49.35 ± 1.44% for Ya-1. In greenhouse trials, R3 significantly boosted pepper growth, with a 22.12% increase in plant height, 46.44% more leaves, and 56.29% greater fresh weight. These enhancements were likely due to the strong affinity between R3 and pepper plants. Both strains also improved soil quality, with R3 increasing available potassium (AK) by 5.13% and soil organic matter (SOM) by 4.03%, while Ya-1 showed more significant increases. Metagenomic analysis revealed that both strains altered the rhizosphere microbiome, with R3 promoting Pseudomonas and suppressing Fusarium. These results suggest that the R3 strain has strong potential for enhancing pepper growth, improving soil health, and reshaping the rhizosphere microbiome.

Keywords: Bacillus velezensis; antifungal activity; biological control; metagenomic; plant growth-promoting microorganisms; soil rhizosphere community.

Grants and funding

The author(s) declare that financial support was received for the research, authorship, and/or publication of this article. This research was funded by the Project of the Hainan Natural Science Fund (324MS120), the Highlevel talent program of Natural Science Foundation of Hainan Province (324RC537), the Innovative team Project of Hainan Academy of Agricultural Sciences (HAAS2023TDYD12), and the Project of Financial Science and Technology Plan of Hainan Province (FW20230002).