AUTHOR=Sun Chaofang , Li Qiao , Han Lingling , Chen Xue , Zhang Fengjuan 

TITLE=The effects of allelochemicals from root exudates of Flaveria bidentis on two Bacillus species

JOURNAL=Frontiers in Plant Science

VOLUME=13

YEAR=2022

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2022.1001208

DOI=10.3389/fpls.2022.1001208

ISSN=1664-462X

ABSTRACT=<p>To determine the allelopathic effects of root exudates from <italic>Flaveria bidentis</italic> on function of <italic>Bacillus</italic>, pot experiment was used to collect root exudates from living plants and test its allelopathic effects on function of <italic>Bacillus frigoritolerans</italic> and <italic>Bacillus megaterium</italic>, which were two dominant bacteria in the rhizosphere soil of <italic>F. bidentis</italic>. To obtain the allelopathic substances, the root exudates were successively extracted by N-hexane, dichloromethane, ethyl acetate, and N-butanol, and their allelopathic effects were tested. The results showed that <italic>B. frigoritolerans</italic> and <italic>B. megaterium</italic> considerably increased the concentration of available phosphorus and nitrogen, respectively, when the soil was treated with different concentrations of root exudates. Among the four organic solvent extracts, dichloromethane extracts significantly increased the abundances of <italic>B. frigoritolerans</italic> and <italic>B. megaterium</italic> and promoted their nitrogen-fixing and phosphate-solubilizing abilities. Phenol was detected in dichloromethane extracts by gas chromatograph-mass spectrometer (GC-MS). Meanwhile, phenol promoted the ability to fix nitrogen of <italic>B. megaterium</italic> and its growth by increasing the soil available nitrogen concentration, but phenol promoted the ability to solubilize phosphate of <italic>B. frigoritolerans</italic> only in 0.1mg/mL concentration. Therefore, phenol was an allelochemicals in the root exudates of <italic>F. bidentis</italic> that affects the growth and activities of <italic>B. megaterium.</italic></p>