ศูนย์นวัตกรรมเทคโนโลยีหลังการเก็บเกี่ยว

Minimum gaseous sulphur dioxide concentrations and exposure periods to control Botrytis cinerea.

Smilanick, J. L.; Henson, D. J.;

Crop Protection Year: 1992 Vol: 11 Issue: 6 Pages: 535-540 Ref: 26 ref.

1992

บทคัดย่อ

The concn of SO2 required to kill the spores and mycelium of B. cinerea and control postharvest decay of fresh grapes were determined in chamber studies. Effective concn and exposure times were simultaneously expressed in a single dosage term, parts per million-hours (p.p.m.-h) (the product of the concn of SO2 in p.p.m. multiplied by the duration of the fumigation in hours). SO2 dosages that killed 99% of the spores were 78.3 plus or minus 22.3 p.p.m.-h at 0 deg C and 20.3 plus or minus 2.0 p.p.m.-h at 20 deg . These values were determined with continuous concn of 25, 50, 100 and 200 p.p.m. SO2 at high humidity. The mycelium on the surface of infected berries was injured by dosages of 10 p.p.m.-h and was no longer viable after fumigation with dosages of 50-100 p.p.m.-h at 0 deg C. Infection of inoculated berries at 0 deg C compared with the controls was 68, 47, 2 and 0% after dosages of 20, 50, 100 and 200 p.p.m.-h., respectively. Reduction in the percentage infection after spore inoculation of berries required a larger dosage (c.100 p.p.m.-h) than that which controlled mycelial growth (c. 50 p.p.m.-h). For initial fumigation of grapes after harvest, where control of spores on the surface of grapes is required, 100 p.p.m.-h should be sufficient; for subsequent storage fumigations where control of mycelial growth from latent infections is required, 50 p.p.m.-h should be sufficient. Colorimetric dosimeters were developed to quantify exposures of humans to SO2 for safety purposes.