Kang, K.; Niu, Z.; Zhang, W.; Wei, S.; Lv, Y.; Hu, Y. Antagonistic Strain Bacillus halotolerans Jk-25 Mediates the Biocontrol of Wheat Common Root Rot Caused by Bipolaris sorokiniana. Plants2023, 12, 828.
Kang, K.; Niu, Z.; Zhang, W.; Wei, S.; Lv, Y.; Hu, Y. Antagonistic Strain Bacillus halotolerans Jk-25 Mediates the Biocontrol of Wheat Common Root Rot Caused by Bipolaris sorokiniana. Plants 2023, 12, 828.
Kang, K.; Niu, Z.; Zhang, W.; Wei, S.; Lv, Y.; Hu, Y. Antagonistic Strain Bacillus halotolerans Jk-25 Mediates the Biocontrol of Wheat Common Root Rot Caused by Bipolaris sorokiniana. Plants2023, 12, 828.
Kang, K.; Niu, Z.; Zhang, W.; Wei, S.; Lv, Y.; Hu, Y. Antagonistic Strain Bacillus halotolerans Jk-25 Mediates the Biocontrol of Wheat Common Root Rot Caused by Bipolaris sorokiniana. Plants 2023, 12, 828.
Abstract
Common root rot caused by Bipolaris sorokiniana infestation of wheat is one of the main reasons of yield reduction in wheat crops worldwide. In current study, strain JK-25 was isolated from soil of wheat rhizosphere and identified as Bacillus halotolerans based on morphological, physiological, biochemical characteristics and molecular identification. The strain showed significant antagonism to B.sorokiniana and broad-spectrum resistance to Fusarium oxysporum, Fusarium graminearum and Rhizoctonia zeae. Inhibition of Bipolaris sorokiniana mycelial dry weight and spore germination rate by JK-25 fermentation supernatant reached 60% and 88% respectively. The crude extract of JK-25 was found by MALDI-TOF-MS to contain the surfactin that exerted an inhibitory effect on B.sorokiniana. The disruption of mycelial cell membranes was observed under microscopy (LSCM) after treatment of B.sorokiniana mycelium with the crude extract. The antioxidant enzyme activity of B.sorokiniana was significantly reduced and the oxidation product MDA content increased after treatment with the crude extract. The incidence of root rot was significantly reduced in pot experiments with the addition of JK-25 culture ferment, which had a significant biological control effect of 72.06%. Its ability to produce siderophores may help to promote wheat growth, and the production of proteases and pectinases may also be part of the strain's role in suppressing pathogens. These results demonstrate the excellent antagonistic effect of JK-25 against B.sorokiniana and suggest that this strain has great potential as a resource for biological control of wheat root rot strains.
Keywords
Bipolaris sorokiniana; Bacillus halotolerans; common root rot; biocontrol agent; wheat
Subject
Biology and Life Sciences, Agricultural Science and Agronomy
Copyright:
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