Evaluation of some fungal and bacterial culture filtrates in controlling preservative solution microorganisms and gray mould rot of Gladiolus hybrida CV. Peter pears spikes [electronic resource].

Includes reference.

This work was carried out at the Faculty of Agriculture, Kafr EI-Sheikh University using two batches, the first on January 2nd and thesecond on July 15th during 2008 season. Vase-life of Gladiolus hybrida cv. Peter pears spikes is determined by many reasons. Among the most common reason for early senescence of fresh spikes is the inability of spikes to absorb water due to their rot and blockage by microor';/anisms. Culture filtrates (CFs) of Epicoccum nigricum, E. purpurascens, Trl choderma viride, Trichoderma harzianum and Bacillus subtilis were evaluated to abscission this reason compared to AgNO at 10ppm. Using CFs in preservative solution significantly decreased the rots of spikes base by minimizing microbial density. Deteriorated florets also were decreased. In contrast, vase-life of gladioli spikes was significantly increased. Highest number of open florets and water uptake of gladioli spikes were recorded when silver nitrate, culture filtrates of B. subtilis were added to preservative solution comparing to the control. Although some culture filtrates i.e. Bacillus subtilis and Epicoccum nigrum surpassed AgN03 in some characters, AgN03 prolonged the flower longevity more than CFs. Gray mould rot of gladioli caused by Botrytis cinerea is considered also one of the most postharvest dangerous diseases of gladioli spikes. The aforementioned CFs were tested for their effectiveness against Botrytis cinerea in-vitro and in-vivo. The antifungal activity of CFs at the used three different concentrations (10, 20 and 30%) was compared in litro on the basis of linear growth inhibition of Botryt;s cinerea. Highly significant effect wasalways achieved with culture filtrates of B. subtilis, E. nigricum and E. purpurascens. In vivo control capability of culture filtrates (CFs) of E. nigricum, E. purpurascens and B. subtilis at concentratic ns of 10, 20 and 30% against gray mould of gladioli spikes under 20±2°C showd that culture filtrate of B. subtilis at both concentrations 20 and 30% significantly prolong vase-life of gladioli spikes up to 15.6 and 13.3 days respectively compared with control (7.0 days). Culture filtrate of B. subtilis and E. nigricum at 20 and 30% played a role in retarding the development 01 the grey mould symptoms caused by B. cinerea on gladioli spikes.

Summary in Arabic.

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