Effects of Meyerozyma guilliermondii PJ15 on the biocontrol of Penicillium crustosum causing postharvest decay in Orah and its influence on the microbial diversity of Orah

Abstract

Abstract Objectives Isolate biocontrol microorganisms that inhibit Penicillium crutosum, and explore their effects on the microbial control and microbial diversity change of Penicillium crustosum causing postharvest decay in Orah. Materials and Methods The biocontrol effect was verified by confrontation experiment. The microbial diversity was analyzed using high-throughput sequencing technology. Metabolomics analysis was performed using LC-MS/MS. Results a strain of Meyerozyma guilliermondii PJ15 that strongly inhibited Penicillium crustosum was isolated from grape surface, which could effectively inhibit the mycelium growth and green spore production of Penicillium crustosum. PJ15 could reduce the sourness and nutrient loss of Orah caused by Penicillium crutosum. Compared with the control, PJ15 treatment increased pH by 11.32%, soluble protein by 154.51%, ascorbic acid by 160.99%, and soluble total sugar by 203.53%. Microbial diversity analysis showed that PJ15 has a relatively small impact on the bacterial composition and diversity on the surface of Orah, but has a significant impact on the fungal composition and diversity. It can increase the fungal diversity of Orah invaded by Penicillium crustosum, increase the density of fungal interaction networks, and form a stronger coexisting survival interaction network. The vaccination of PJ15 downregulated differential metabolites 5,6-Epoxytetraene, which showed a positive correlation with Penicillium crustosum and a negative correlation with PJ15. Conclusions Meyerozyma guilliermondii PJ15 has a strong inhibitory effect on the growth of Penicillium crustosum, and has a significant impact on the fungal composition and diversity on the surface of Orah. It has the potential for biocontrol of Penicillium crustosum causing postharvest decay in Orah.