Author
ZHANG, QINGHUA - Huazhong Agricultural University | |
YANG, LONG - Huazhong Agricultural University | |
ZHANG, JING - Huazhong Agricultural University | |
WU, MINGDE - Huazhong Agricultural University | |
Chen, Weidong | |
JIANG, DAOHONG - Huazhong Agricultural University | |
LI, GUO-QING - Huazhong Agricultural University |
Submitted to: Plant and Soil
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 3/11/2015 Publication Date: 3/21/2015 Citation: Zhang, Q., Yang, L., Zhang, J., Wu, M., Chen, W., Jiang, D., Li, G. 2015. Production of anti-fungal volatiles by non-pathogenic Fusarium oxysporum and its efficacy in suppression of verticillium wilt of cotton. Plant and Soil. 392:101-114. Interpretive Summary: Fungi produce diverse secondary metabolites and some of the secondary metabolites are volatile organic compounds (VOCs). These secondary metabolites including VOCs can be exploited for managing plant diseases. This research explores the VOCs produced by a nonpathogenic isolate CanR-46 of Fusarium oxysporum for suppressing Verticillium wilt. The VOCs showed antagonistic activity against 14 fungal species including the important plant pathogen Verticillium dahlia. A total of 19 compounds were identified in the VOCs and eremophila-1 (10),11-diene was the most abundant. Four synthetic compounds (5-hexenoic acid, limonene, 3,4-2H-dihydropyran and octanoic acid) showed antifungal activity against V. dahliae. The VOCs of isolate CanR-46 significantly reduced Verticillium wilt of cotton. The results suggest that the VOC-producing isolate CanR-46 is a promising biocontrol agent against Verticillium wilt Technical Abstract: Aims: The study aimed to identify volatile organic compounds (VOCs) produced by the non-pathogenic Fusarium oxysporum (Fo) strain CanR-46, and to determine the anti-fungal spectrum and the control efficacy of the Fo-VOCs. Methods: The Fo-VOCs were identified by GC-MS. The antifungal activity of the Fo-VOCs was tested using the double-dish method. Soil contaminated with Verticillium dahliae was fumigated with the Fo-VOCs to test the control efficacy. The GFP-tagged derivative strain CanR-46GFP was tested to colonize cotton roots for prevention of infection by V. dahliae. Results: Nineteen VOCs were identified with eremophila-1 (10),11-diene being the most abundant. The Fo-VOCs inhibited mycelial growth of 14 fungal species including V. dahliae, delayed V. dahliae conidial germination, suppressed V. dahliae germ-tube elongation, and caused V. dahliae hyphal shriveling and collapse. Four synthetic chemicals, 5-hexenoic acid, limonene, octanoic acid and 3,4-2H-dihydropyran, showed antifungal activity against V. dahliae. The Fo-VOCs significantly (P < 0.05) reduced severity of Verticillium wilt of cotton compared to the control. CanR-46GFP extensively colonized cotton root tissues, which effectively prevented V. dahliae infection. |