The fungus Botrytis is known to cause rot in fruit and decrease the harvest. In an effort to limit the damage, some agriculturalists spray the soil of orchards with fungicides. The effect of fungicides is not specific for Botrytis and kills most fungi in the soil. In a short answer, predict what would happen to the yield of grapes following fumigation and explain the rationale for your prediction.
A research was conducted to determine the effect of bio fungicides on the microbial community of wine making. Bacteria Bacillus subtilis (specifically the strain QST713) is an interesting biological control agent against Botrytis. The study aimed mainly the action of strain at three stages namely vinification, grape biofilm, musts and wines. The results were compared with a applied chemical fungicide and a control sample. For the study culture dependent and culture independent techniques were employed. There was no evidence of grape samples being infected by Botrytis and so the health grape state was adequate.
After checking the impact of biological fungicides on grape biofilm some differences were observed when compared with chemical fungicides. By culture independent methods gray mold or B.cinerea was detected, not being found either in control sample or grape with bio-fungicide. Also Pseudomonas genus was found in all samples after applying both fungicides, but not in control. In total, microbial community of grape wine was not much modified after applying both fungicides.
When checked the effects on grapes at must stage, it was observed that, chemical fungicide applied to grape have some kind of impact on microbial community. When checked with wine microbiota, at sampling stage a difference in microbial diversity was established in the samples proceeding from grapes when treated with chemical fungicides. The sample was much different from other two samples. The sample had low richness of species, lower diversity and lower number of odd species. These factors made the sample low sensitive to external threats. Also probability of finding two random selected individuals of same species from the sample was less. This means that chemical fungicides were neutral in terms of the structure of microbial community.
To sum up, by checking various conditions and with the protocols used, it was clear that bio-fungicide had no impact on alpha microbial diversity till the end of fermentation. Also bio-fungicide can be applied to the vine as a biological control.
The fungus Botrytis is known to cause rot in fruit and decrease the harvest. In an...