НЕКОТОРЫЕ МЕТОДИЧЕСКИЕ ПОДХОДЫ К ВЫДЕЛЕНИЮ И ИЗУЧЕНИЮ ДЕЙСТВИЯ ТОКСИЧЕСКИХ ВЕЩЕСТВ ГРИБА ALTERNARIA НА ПРОРОСТКИ ТОМАТОВ

Светлана НИКОЛАЕВА, Аркадий НИКОЛАЕВ, Виктория ШУБИНА, Леонид ВОЛОЩУК Институт защиты растений и экологического земледелия АН Молдовы

Abstract

The objectives of our research were to: - select of the local isolates of the fungus Alternaria with high toxigenic properties; - select of the most optimal cultivation conditions of the pathogen for the production of water-soluble toxins; - provide a water-soluble toxin; - select of the tomatoes varieties which are most sensitive to the alternaria toxins; - evaluate of toxigenic properties of Alternaria isolates on the seedlings of tomatoes. It was established that isolates of Alternaria differs in their toxigenicity. Cultivar of tomato more sensitive to alternarioses is more sensitive to the toxin than the more resistant. At 20oC toxicity is more pronounced than at 27oC. Toxicity of isolates of the fungus depends on the composition of the medium on which the fungus is grown. The aqueous extract of mycelium was less toxic than the culture medium. Toxigenicity of isolates depends of the peculiarities of Alternaria isolates, and the medium on which isolates were cultivated. The presence of conidia in the aqueous extract of mycelium led to the stimulation of seedlings development. This was noted for all isolates and in all nutrient media.