Effects of Ozone Treatment on Botrytis cinerea and Sclerotinia sclerotiorum in Relation to Horticultural Product Quality

Abstract

Botrytis cinerea and Sclerotinia sclerotiorum are fungal pathogens that cause the decay of many fruits and vegetables. Ozone may be used as an antimicrobial agent to control the decay. The effect of gaseous ozone on spore viability of B. cinerea and mycelial growth of B. cinerea and S. sclerotiorum were investigated. Spore viability of B. cinerea was reduced by over 99.5% (P < 0.01) and height of the aerial mycelium was reduced from 4.7 mm in the control to less than 1 mm after exposure to 450 or 600 ppb ozone for 48 h at 20 degrees C. Sporulation of B. cinerea was also substantially inhibited by ozone treatments. However, ozone had no significant effect on mycelial growth of S. sclerotiorum in vitro. Decay and quality parameters including color, chlorophyll fluorescence (CF), and ozone injury were further assessed for various horticultural commodities (apple, grape, highbush blueberry, and carrot) treated with 450 ppb of ozone for 48 h at 20 degrees C over a period of 12 d. Lesion size and height of the aerial mycelium were significantly reduced by the ozone treatment on carrots inoculated with mycelial agar plugs of B. cinerea or S. sclerotiorum. Lesion size was also reduced on treated apples inoculated with 5 x 10(6) spores/mL of B. cinerea, and decay incidence of treated grapes was reduced. The 450 ppb ozone for 48 h treatment had no significant effect on color of carrots and apples or on CF of apples and grapes. Ozone, an environmentally sound antimicrobial agent, inactivates microorganisms through oxidization and residual ozone spontaneously decomposes to nontoxic products. It may be applied to fruits and vegetables to reduce decay and extend shelf life.

Effects of modified atmosphere packing and honey dip treatments on quality maintenance of minimally processed grape cv. Razaki (V. vinifera L.) during cold storage

“…Increasing pressure in the food conservation field to replace chemical-based applications has urged researchers to focus on studying new reliable and healthy strategies of extending the postharvest and shelf life of produces (Tharanathan 2003). Previously, a number of materials were tested for their preservative potentials and appropriateness to organic consumption during storage of produces, such as ethanol (Karabulut et al 2004;Lichter et al 2002;Sabir et al 2006), mineral oils (Valero et al 2006), chlorinated or hot water (Del Nobile et al 2008), ethephon (Jayasena and Cameron 2009), chitosan (a natural polysaccharide) (Romanazzi et al 2009), and ozone (Sharpe et al 2009). In these endeavors, undesirable odors or bitterness that may confer to the produces during storage have been significant limitations in practical applications of such materials (Soliva-Fortuny and Martín-Belloso 2003;Mishra et al 2010).…”

Ozônio como agente fitossanitário na conservação pós-colheita da batata-baroa

“…Foi observada oscilação diária dos dados de variação de cor, o que pode ter ocorrido devido ao fato de a podridão-mole apresentar lesões pontuais e a amostragem ser aleatória. Semelhantemente, Sharpe et al (2009) Durante o armazenamento de produtos agrícolas, pode ocorrer degradação de reservas de carboidratos, em que o amido é hidrolisado a sacarose e esta, por sua vez, em açúcares redutores, liberando dióxido de carbono e água (BHERING et al, 2009). Esse processo respiratório pode, portanto, alterar o teor de açúcares, em batatas armazenadas.…”

The practicality of using ozone with fruit and vegetables

“…Alwi and Ali have shown that ozone was more effective in reducing microbial populations of Listeria monocytogenes and E. coli O157 than Salmonella enterica on fresh‐cut bell peppers, and suggested that higher resistance of S. enterica could be associated with higher density of its cell membrane due to higher content of phospholipid components . Similarly, Sclerotinia sclerotiorum was found to be more resistant to ozone exposure than B. cinerea , and Colletotrichum coccodes more resistant than Alternaria alternata on artificially inoculated carrots and tomato fruit, respectively. In this context, continuous exposure to ozone at 0.3 µmol mol −1 significantly reduced disease severity and decay in peaches inoculated with Monilinia fructicola , while having no effect on decay in fruit inoculated with B. cinerea , Mucor piriformis or Penicillium expansum .…”

“…It has been demonstrated in a number of studies that exposure to ozone reduces the production of spores in many fungi, e.g. in B. cinerea exposed to ozone at 0.45 and 0.6 µmol mol −1 for 48 h, in B. cinerea , M. fructicola , M. piriformis , P. expansum wound‐inoculated on peaches, and B. cinerea inoculated on kiwi fruit when continuously exposed to ozone at 0.3 µmol mol −1 . When the produce is removed from the ozone‐enriched atmosphere, however, the production of spores often resumes.…”