STORAGE IMPACT ON BULB GERMINATION OF GARLIC AND PATHOGENIC SPECIES OF Penicillium AND Erwinia ASSOCIATED

Abstract

In México information about the postharvest physiology of garlic (Allium sativum L.) and the pathogenic microorganisms associated during its storage is scarce. This work evaluated the influence of the storage conditions in an open-roof (TA) storehouse and in a closedroof (TC) storehouse on the germination rate and on the sanitary conditions of garlic bulbs (cvs. Tacátzcuaro, Tocumbo, Chetumal and María Luisa) and identified the phytopathogenic species of fungi and bacteria associated to them. Harvested garlic bulbs originally presented several damages by: insect (52 %), mechanical (26 %), fungal (14 %) and physiological (8.8 %). The percentage of damaged bulbs by fungi did not increase during storage (70 d). Germination rate of garlic bulbs stored in TA storehouse at 22.7 oC and 61.4 % RH was 44 %, and in the TC storehouse at 29.0 oC and 56.2 % RH was 32 %. Germination in garlic bulbs placed at 1 m and 4 m heights were 41 % and 35 %, respectively. Penicillium and Fusarium were the most frequently isolated fungi, with 90 % and 70 % of infected bulbs, respectively. The Penicillium strains that resulted pathogenic on clove halves were identified as P. hirsutum Dierckx and P. citrinum Thom. According to its physiological and biochemical characteristics, the only phytopathogenic bacterial strain corresponded to Erwinia carotovora. Fusarium strains were non-pathogenic.