Open AccessApplications of Chlorine Dioxide Gas for Control of Bacterial Soft Rot in Tomatoes
Author(s) -
Michael J. Mahovic,
Joel Tenney,
Jerry A. Bartz
Publication year - 2007
Publication title -
plant disease
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.663
H-Index - 108
eISSN - 1943-7692
pISSN - 0191-2917
DOI - 10.1094/pdis-91-10-1316
Subject(s) - chlorine dioxide , inoculation , sodium chlorite , horticulture , biology , sodium hypochlorite , incubation period , lycopersicon , incubation , erwinia , microbiology and biotechnology , bacteria , chemistry , organic chemistry , genetics , inorganic chemistry , biochemistry
Chlorine dioxide (ClO 2 ) gas was generated from a mixture of sodium chlorite and ferric chloride plus water (impregnated into zeolite) in a Tyvek sachet over a 2- or 24-h period. The gas was distributed by a fan over wound-inoculated tomato fruit (Lycopersicon esculentum) enclosed in a sealed aluminum pressure cooker. Within 24 h of inoculation with 6 log 10 CFU of Erwinia carotovora subsp. carotovora per wound and storage at 22 to 24°C, bacterial soft rot was observed on >80% of the nontreated wounds (10 wounds/fruit and 4 or 6 fruit/treatment). By contrast, wounds that had been exposed to an atmosphere containing up to 99 mg ClO 2 during a 2- or 24-h period remained firm and dry with no evidence of bacterial activity or soft rot. After 72 h of incubation, wounds exposed to 88 mg ClO 2 produced over 24 h or 99 mg ClO 2 produced over 2 h were free of decay, whereas bacterial soft rot was observed in ca. 12% and less than 5% of wounds treated with 0.75 mg or 7.5 mg, respectively, for either 2 or 24 h. Wounds that had not been inoculated remained free of bacterial soft rot throughout the entire storage period. Wounds exposed to the highest doses of ClO 2 , 88 mg/24 h or 99 mg/2 h, became bleached and sunken. Additionally, the stem scars on these fruit became cracked, sunken, and bleached. The intact cuticle was not visibly affected, and there was no observed change in overall fruit color. ClO 2 gas may be effective for controlling postharvest decays of fruit that have been inoculated prior to or during harvest.