Isolation and characterization of plant growth-promoting endophytic bacteria Bacillus stratosphericus LW-03 from Lilium wardii

Abstract

In the present study, a new strain of Bacillus stratosphericus LW-03 was isolated from the bulbs of Lilium wardii. The isolated endophytic strain LW-03 exhibited excellent antifungal activity against common plant pathogens, such as Fusarium oxysporum, Botryosphaeria dothidea, Botrytis cinerea, and Fusarium fujikuroi. The growth inhibition percentage of Botryosphaeria dothidea was 74.56 ± 2.35%, which was the highest, followed by Botrytis cinerea, Fusarium fujikuroi, and Fusarium oxysporum were 71.91 ± 2.87%, 69.54 ± 2.73%, and 65.13 ± 1.91%, respectively. The ethyl acetate fraction revealed a number of bioactive compounds and several of which were putatively identified as antimicrobial agents, such as 4-hydroxy-2-nonenylquinoline N-oxide, sphingosine ceramides like cer(d18:0/16:0(2OH)), cer(d18:0/16:0), and cer(d18:1/0:0), di-peptides, tri-peptide, cyclopeptides [cyclo(D-Trp-L-Pro)], [cyclo (Pro-Phe)], dehydroabietylamine, oxazepam, 1-palmitoyl-2-arachidonoyl-sn-glycero-3-phosphocholine like compound (PC(0:0/20:4), phosphatidylethanolamine (PE(18:1/0:0)), 3-Hydroxyoctadecanoic acid, 7.alpha.,27-Dihydroxycholesterol, N-Acetyl-d-mannosamine, p-Hydroxyphenyllactic acid, Phytomonic acid, and 2-undecenyl-quinoloin-4 (1H). The LW-03 strain exhibits multiple plant growth-promoting traits, including the production of organic acids, ACC deaminase, indole-3-acetic acid (IAA), siderophores, and nitrogen fixation activity. The beneficial effects of the endophytic strain LW-03 on the growth of two lily varieties were further evaluated under greenhouse conditions. Our results revealed plant growth-promoting activity in inoculated plants relative to non-inoculated control plants. The broad-spectrum antifungal activity and multiple plant growth-promoting properties of Bacillus stratosphericus LW-03 make it an important player in the development of biological fertilizers and sustainable agricultural biological control strategies.

Antimicrobial Activity Against Phytopathogens and Inhibitory Activity on Solanine in Potatoes of the Endophytic Bacteria Isolated From Potato Tubers

“…The bioactive secondary metabolites such as alkaloids, terpenoids, phenols, antibiotics, and anti-cancerous compounds produced by endophytic bacteria have been applied in agricultural, industrial, and medical fields ( Christina et al, 2013 ; Gao et al, 2015 ; Liu et al, 2015 ; Yamada et al, 2015 ; Hashem et al, 2016 ). Bacillus stratosphericus LW-03 isolated from the bulbs of Lilium wardii exhibited multiple plant growth-promoting traits, including the production of indole-3-acetic acid (IAA), organic acids, and siderophores ( Khan et al, 2020 ). The fermentation broth of Aranicola proteolyticus , Bacillus licheniformis , Bacillus thuringiensis , Bacillus cereus , and Serratia liquefaciens isolated from Pinellia ternata (Thunb.)…”

Genomic Analysis of Endophytic Bacillus cereus T4S and Its Plant Growth-Promoting Traits

“…The qualitative screening of B. cereus T4S for the solubilization of phosphate was performed according to the modified method of Khan et al [ 74 ]. For the quantitative assay, phosphate solubilization tendencies of the bacteria isolate were performed by inoculating 10 mL sterile Pikovskaya broth in 50 mL Falcon tubes with 0.1 mL (10 6 CFU/mL) freshly grown bacterial culture, incubated at 30 °C for 120 h at 180 rpm on a rotary shaker machine.…”

“…Siderophore producing ability of B. cereus T4S was performed on chrome azurol S (CAS) medium following the methods of Khan et al [ 74 ] with little modifications. The quantity of siderophore produced was determined by inoculating LB broth solution containing CAS with 0.1 mL of 24-h old bacterial culture and incubated at 180 rpm on a rotary shaker for 164 h. Centrifugation of bacterial culture suspension was achieved at 8000× g for 10 min.…”

“…The circular genome visualization was obtained from kbase (https://kbase.us/) (accessed on the 23 July 2021), while the phylogeny analysis was performed using MrBayes (http://www.phylogeny.fr/one_task.cgi?task_type=mrbayes) (accessed on the 23 July 2021) (version 3.2.6) [68,72]. Secondary metabolites were determined by antiSMASH (version 6.0.0) (https://antismash.secondarymetabolites.org) (accessed on the 26 June 2021) [73] The qualitative screening of B. cereus T4S for the solubilization of phosphate was performed according to the modified method of Khan et al [74]. For the quantitative assay, phosphate solubilization tendencies of the bacteria isolate were performed by inoculating 10 mL sterile Pikovskaya broth in 50 mL Falcon tubes with 0.1 mL (10 6 CFU/mL) freshly grown bacterial culture, incubated at 30 • C for 120 h at 180 rpm on a rotary shaker machine.…”

Effect of Endophytic Bacteria on Tomato Plant Growth Promotion and Tomato Early Blight Management

“…The isolate EBT18 has also recorded siderophore production which might be the reason for the antagonistic activity of EBT18 against A. solani under in vitro (53.84 per cent inhibition) and glass house conditions. Similarly, the endophytic bacteria Bacillus stratosphericus strain LW-O3 isolated from Lilium wardii was found to be antagonistic towards four fungal pathogens namely, Botryosphaeria dothidea, Botrytis cinerea and Fusarium fujikuroi and Fusarium oxysporum with an inhibition percentage of 74.56 ± 2.35%, 71.91 ± 2.87%, 69.54 ± 2.73% and 65.13 ± 1.91% respectively (Khan et al, 2020).…”