Sawai Boukaew1, Benjamas Cheirsilp2, Poonsuk Prasertsan3, Siriporn Yossan4. 1. College of Innovation and Management, Songkhla Rajabhat University, Songkhla, 90000, Thailand. 2. Department of Industrial Biotechnology, Faculty of Agro-Industry, Prince of Songkla University, Hatyai, 90112, Thailand. 3. Research and Development Office, Prince of Songkla University, Hatyai, Songkhla, 90112, Thailand. 4. Division of Environmental Science, Faculty of Liberal Arts and Science, Sisaket Rajabhat University, Sisaket, 33000, Thailand.
Abstract
AIMS: Application of volatile organic compounds from Streptomyces salmonis PSRDC-09 (VOCs PSRDC-09) grown on sterile wheat seeds against chili anthracnose pathogen was investigated in vitro and in vivo. METHODS AND RESULTS: Among 10 isolates of Colletotrichum species tested, C. gloeosporioides PSU-03 was selected as the most aggressive anthracnose pathogenic strain on chili fruit against volatile organic compounds produced by Streptomyces species. Among 11 isolates, the strain PSRDC-09 exhibited the highest antifungal activity and was identified as S. salmonis PSRDC-09. The antagonistic mechanism of the VOCs PSRDC-09 on morphological of C. gloeosporioides PSU-03, observed by scanning electron microscope (SEM), revealed the irregular distortions in the fungal hyphae. The effect of inoculum size and spore concentration of S. salmonis PSRDC-09 prepared as a wheat seed inoculum on the suppression of C. gloeosporioides PSU-03 was studied both in vitro and on chili fruit. The optimum inoculum size (45 g 0.31 L-1 ) and spore concentration (107 spore mL-1 ) of the wheat seed culture of S. salmonis PSRDC-09 exhibited the complete suppression (100 % inhibition) on C. gloeosporioides PSU-03. The optimum fumigation period of the VOCs PSRDC-09 (45 g 1.38 L-1 ) was found to be 24 h. Based on gas chromatography-mass spectrometry (GC-MS) analysis, 14 major VOCs (produced by the strain PSRDC-09) were detected and l-linalool was the main volatile component. CONCLUSIONS: The results indicated that the VOCs from S. salmonis PSRDC-09 could effectively control the chili anthracnose disease caused by C. gloeosporioides. SIGNIFICANCE AND IMPACT OF THE STUDY: These findings suggest that S. salmonis PSRDC-09 may have the potential to become a promising biofumigant for biocontrol of chili anthracnose disease in the postharvest system. This article is protected by copyright. All rights reserved.
AIMS: Application of volatile organic compounds from Streptomyces salmonisPSRDC-09 (VOCs PSRDC-09) grown on sterile wheat seeds against chili anthracnose pathogen was investigated in vitro and in vivo. METHODS AND RESULTS: Among 10 isolates of Colletotrichum species tested, C. gloeosporioidesPSU-03 was selected as the most aggressive anthracnose pathogenic strain on chili fruit against volatile organic compounds produced by Streptomyces species. Among 11 isolates, the strain PSRDC-09 exhibited the highest antifungal activity and was identified as S. salmonisPSRDC-09. The antagonistic mechanism of the VOCs PSRDC-09 on morphological of C. gloeosporioidesPSU-03, observed by scanning electron microscope (SEM), revealed the irregular distortions in the fungal hyphae. The effect of inoculum size and spore concentration of S. salmonisPSRDC-09 prepared as a wheat seed inoculum on the suppression of C. gloeosporioidesPSU-03 was studied both in vitro and on chili fruit. The optimum inoculum size (45 g 0.31 L-1 ) and spore concentration (107 spore mL-1 ) of the wheat seed culture of S. salmonisPSRDC-09 exhibited the complete suppression (100 % inhibition) on C. gloeosporioidesPSU-03. The optimum fumigation period of the VOCs PSRDC-09 (45 g 1.38 L-1 ) was found to be 24 h. Based on gas chromatography-mass spectrometry (GC-MS) analysis, 14 major VOCs (produced by the strain PSRDC-09) were detected and l-linalool was the main volatile component. CONCLUSIONS: The results indicated that the VOCs from S. salmonisPSRDC-09 could effectively control the chili anthracnose disease caused by C. gloeosporioides. SIGNIFICANCE AND IMPACT OF THE STUDY: These findings suggest that S. salmonisPSRDC-09 may have the potential to become a promising biofumigant for biocontrol of chili anthracnose disease in the postharvest system. This article is protected by copyright. All rights reserved.