Biocontrol of Postharvest Grey Mould on Tomato by Yeasts

Abstract

The fungal pathogen Botrytis cinerea causes severe rots on tomato fruit during storage and shelf life. Biological control of postharvest diseases of fruit may be an effective alternative to chemical control. Yeasts are particularly suitable for postharvest use, proving to be highly effective in reducing the incidence of fungal pathogens. Yeast fungi isolated from the surface of solanaceous plants were evaluated for their activity in reducing the postharvest decay of tomato caused by B. cinerea. Of 300 isolates, 14 strains of Rhodotorula rubra and Candida pelliculosa were found to be strongly antagonistic to the pathogen in vitro and were selected for further storage experiment. The antagonists were evaluated for their effect on the biological control of postharvest grey mould. Artificially wounded fruits were treated by means of a novel technique: small sterile discs of filter paper imbibed separately in suspensions of each yeast and the pathogen were superposed onto each wound. After 1-week, 11 isolates were significantly effective in reducing the diameter of lesions by more than 60% compared to the control treated with B. cinerea alone. Total protection was obtained with the strain 231 of R. rubra on fruits challenged with pathogen spores. To our knowledge, R. rubra and C. pelliculosa have not been described as biocontrol agents against grey mould caused by B. cinerea. Our data demonstrate that the application of antagonistic yeasts represents a promising and environmentally friendly alternative to fungicide treatments to control postharvest grey mould of tomato.

Evaluation of yeasts from Tibetan fermented products as agents for biocontrol of blue mold of Nashi pear fruits

“…The optimum concentration was 1×10 8 cells/ml, because at this concentration biocontrol activity was similar to that at 1×10 9 cells/ml. A similar phenomenon was also found in other studies of Rhodotorula yeasts (Castoria et al, 2005;Dal Bello et al, 2008;Zhang et al, 2008;Robiglio et al, 2011). Generally, competition with pathogen for nutrients and space in the wounds of fruits is recognized as the main biocontrol mechanism of antagonistic yeast (Ippolito and Nigro, 2000;Sharma et al, 2009), so the population dynamics of R. mucilaginosa in wounds of pear fruits was used to study its biocontrol mechanism.…”

Isolation and Selection of Epiphytic Yeat for Biocontrol of Botrytis cinerea Pers. on Table Grapes

“…Inhibition zones in the dual cultures could be due to the production of antibiotics, siderophores, toxic or antifungal metabolites used by these organisms as biological control mechanisms, and the size of the observed inhibition zones would represent the concentration and diffusivity of the inhibitory compounds secreted by each isolate (Swadling and Jeffries, 1996). However, production of these compounds in the culture media is not indicative of its production in action sites on the fruits (Dal Bello et al, 2008). …”

“…Yeasts are leading the advances to control pathogens causing fruit rot (McLaughlin et al, 1990;Droby et al, 1998;Spadaro et al, 2002;Vero et al, 2002;Chanchaichaovivat et al, 2007). Several studies have demonstrated an efficient antagonistic activity of yeast against B. cinerea (Saligkarias et al, 2002;Santos et al, 2004;Elmer and Reglinski, 2006;Dal Bello et al, 2008).…”

Endophytic Yeast and Hosts: A Mutualistic Association Friendly to the Environment

“…Therefore, it is possible to use them successfully as agents for biological control [8,9]. Also, some studies have shown that these yeasts foster the growth of plants by means of bringing out auxins, as reported by Nassar et al [10], who isolated the endophytic yeast Williopsis saturnus and found that it is capable of producing indole-3-acetic acid (IAA), a growth hormone.…”