Yanhui Feng, Baoyu Tian, Juan Xiong, Guoqin Lin, Linjie Cheng, Ting Zhang, Bilian Lin, Zhenhua Ke, Xin Li
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引用次数: 0
Abstract
Exploring indoleacetic acid (IAA) biosynthesis pathways of plant growth promoting bacteria and their ability to synthesize IAA is crucial for understanding the promotion mechanism and for developing more efficient microbial fertilizer. In this study, 118 bacterial endophytic strains were isolated from tomato root and 68 isolates were identified as members of Bacillus and Pseudomonas genus. After screening abilities to synthesize IAA in vitro and promote plant growth for these identified Bacillus and Pseudomonas strains, 7 endophytic strains Bacillus sp. Y_21, B. paramycoides Y_29, B. albus Y_96, B. cereus Y_121, P. plecoglossicida Y_157, Bacillus sp. Y_165 and B. aryabhattai Y_170 strains showed a significant promotion role on wheat root or leaf, including 4 endophytic strains with the potential ability to utilize intermediate metabolites, such as tryptamine and indole acetamide, to produce IAA. Genomic sequencing analysis for selected representative plant growth promoting endophytes showed that IAA-producing bacteria B. cereus mr31 and P. putida Y_166 separately harbored a complete indoleacetamide (IAM) and complete tryptamine (TAM) pathway; whereas, Bacillus sp. Y_165 and B. aryabhattai Y_170, two strains producing IAA not using tryptophan but with indole-3-acetamide, had an incomplete IAM pathway. Fermentation experiments of three genome-sequenced strains using wheat or tomato root extracts as substrate, and combining with UHPLC–MS/MS analysis for wheat root extracts, demonstrated that Bacillus sp. Y_165 strain might produce IAA by using the plant-derived indole-3-acetamide. Our study first demonstrated a novel potential mechanism for the plant growth promoting endophytes to biosynthesize IAA using plant-derived intermediates. This additional mechanism has deepened our understanding of how bacterial endophytes promote plant health and resilience, offering valuable insights about how plants regulate IAA homeostasis within their internal tissues in association with bacterial endophytes.
期刊介绍:
Chemical and Biological Technologies in Agriculture is an international, interdisciplinary, peer-reviewed forum for the advancement and application to all fields of agriculture of modern chemical, biochemical and molecular technologies. The scope of this journal includes chemical and biochemical processes aimed to increase sustainable agricultural and food production, the evaluation of quality and origin of raw primary products and their transformation into foods and chemicals, as well as environmental monitoring and remediation. Of special interest are the effects of chemical and biochemical technologies, also at the nano and supramolecular scale, on the relationships between soil, plants, microorganisms and their environment, with the help of modern bioinformatics. Another special focus is the use of modern bioorganic and biological chemistry to develop new technologies for plant nutrition and bio-stimulation, advancement of biorefineries from biomasses, safe and traceable food products, carbon storage in soil and plants and restoration of contaminated soils to agriculture.
This journal presents the first opportunity to bring together researchers from a wide number of disciplines within the agricultural chemical and biological sciences, from both industry and academia. The principle aim of Chemical and Biological Technologies in Agriculture is to allow the exchange of the most advanced chemical and biochemical knowledge to develop technologies which address one of the most pressing challenges of our times - sustaining a growing world population.
Chemical and Biological Technologies in Agriculture publishes original research articles, short letters and invited reviews. Articles from scientists in industry, academia as well as private research institutes, non-governmental and environmental organizations are encouraged.