LOW TEMPERATURE GROWTH AND ENZYME PRODUCTION IN PENICILLIUM SER. CORYMBIFERA SPECIES, CASUAL AGENTS OF BLUE MOLD STORAGE ROT IN BULBS

Abstract

Taxa from the Penicillium ser. Corymbifera are reported as causing a damaging storage rot upon commercially grown vegetables and flower bulbs; however many reports of blue mould rot in the literature are based on outdated taxonomy. Pencillium ser. Corymbifera taxa are unique from other Penicillia because of their ability to grow at 0°C and proliferate at 5°C, their hemi-cellulase and cellulase activity at 5 and 15°C, and lack of protease production. Penicillium hordei differs slightly from this characterization by the production of proteases and Penicillium allii differs by the lack of cellulase and hemicellulase production below 15°C. With the exception of P. allii, all six of the remaining ser. Corymbifera taxa have a potential to proliferate at low temperatures and would therefore cause disease under storage conditions.