ศูนย์นวัตกรรมเทคโนโลยีหลังการเก็บเกี่ยว

Influence of sulfur dioxide fumigant dose on residues and control of postharvest decay of grapes.

Smilanick, J. L.; Harvey, J. M.; Hartsell, P. L.; Henson, D. J.; Harris, C. M.; Fouse, D. C.; Assemi, M.;

Plant Disease Year: 1990 Vol: 74 Issue: 6 Pages: 418-421 Ref: 22 ref.

1990

บทคัดย่อ

Grapes were fumigated with 1250 p.p.m. SO2 for 2 h, 2500 p.p.m. for 1 h, 5000 p.p.m. for 0.5 h, or 10 000 p.p.m. for 0.25 h. The product of SO2 dose and fumigation period in each test was 2500 p.p.m./h. Sulfite residues after fumigation were not significantly different among the first 3 dose combinations. Grape cultivars Flame Seedless and Thompson Seedless contained an av. of 9.6 and 6.1 mu g of sulfite/g FW, respectively. Fumigation with 10 000 p.p.m. for 0.25 h left residues c. 30% higher than the lower doses and bleached Flame Seedless grapes. To determine whether SO2 fumigant doses recommended for commercial use could be reduced to minimize sulfite residues and still control postharvest decay by Botrytis cinerea, 3 commercially packaged grape cultivars in storage at 0 deg C were fumigated for 30 min weekly for 2 months with 312, 625, 1250 or 2500 p.p.m. SO2. Decay control was not significantly different among the doses. Sulfite residues in grapes fumigated weekly with 312 or 625 p.p.m. did not exceed the 10 mu g of sulfite/g FW residue tolerance, whereas those with higher fumigation doses occasionally did. Commonly used commercial doses (5000 - 10 000 p.p.m. for the first fumigation followed by 1000 - 2500 p.p.m. weekly) appeared to be higher than needed for decay control.