LAUSR

To develop an effective and environmentally safe strategy to control postharvest gray mold caused by Botrytis cinerea, Bacillus siamensis strain YJ15 isolated from blueberry was used to test the biocontrol potential. It is interesting to find that the volatile organic compounds (VOCs) emitted from strain YJ15 exhibited significant antifungal activity against B. cinerea as well as other eleven plant pathogenic fungi with the percent of mycelial growth inhibition (PGI) from 74.96% to 92.81%. Additionally, VOCs from strain YJ15 could reduce significantly the disease incidence and lesion diameter with the increasing of fermentation time, indicating great biocontrol potential for controlling blueberry postharvest gray mold. Furthermore, the VOCs were collected by using headspace solid phase microextraction (SPME) fiber, and the composition of VOCs were further revealed by using gas chromatography coupled with quadruple mass spectrometry (GC-MS). Twenty-four kinds of VOCs, including 5 alkanes, 2 aldehydes, 3 ketones, 5 alcohols, 1 alkene, 5 acids & esters, 2 aromatic compounds and 1 sulfur compound, were emitted at 1, 3, 5 and 7 d after inoculation. Among these VOCs, eight antifungal VOCs could inhibit mycelial growth of B. cinerea. It is important to highlight that although 1-butanol and 3-methyl-1-butanol were the most abundant compounds, 2-ethylhexanol, 1-heptanol and 1, 3-xylene have proved to be more toxic to B. cinerea than 3-methyl-1-butanol, propanethioic acid, 2, 2-dimethyl-, ethyl 2-methylbutyrate, 2-heptanone and 1-butanol, which provide new promising bio-fumigant for the control of postharvest gray mold caused by B. cinerea.