Фітотоксична активність деяких мікроміцетів

Abstract

Weeds worsening the conditions of growth and development of agricultural plants cause great damage to the Ukrainian agriculture. One of the methods of biological control of weeds is the use of biogenic products of biosynthesis of microscopic fungi or preparations based on living microorganisms. The aim of work was to test phytotoxic activity of cultural filtrates of 82 micromycete strains of genus Penicillium, Cladosporium, Botrytis, Beauveria, Chaetomium, Curvularia, Endomyces, Fusarium, Gliocladium, Aspergillus, Alternaria, Aureobasidium, Paecilomyces, Mortirella, Nigrospora, Pseudallescheria, Scopulariopsis, Trichoderma, Ulocladium and separate strains Nectria sp., Phialophora sp., Verticillium dahliae isolated from different ecological niches. The micromycetes were grown on a basic nutritive Czapek medium. After 14 days the mycelium was removed through filtration. The culture liquid filtrates were tested against green algae Chlorella vulgaris 190 and seeds of couch-grass, white goosefoot and wheat. The screening phytotoxic study of culture liquid filtrate of micromycete strains against green algae Chlorella vulgaris 190 used standard agar well diffusion method. It is shown that 19 cultures were biological activities only. The wide spectrum of phytotoxic activity was characterized for Cladosporium cladosporiodes 9, Mortirella vinacea 78 и Paecilomyces variotii 69. The strain C. cladosporiodes 9 suppressed the seed germination of couch-grass and white goosefoot and did not suppress the germination of wheat. The strain M. vinacea 78 equally suppressed the germination of seeds like the wheatgrass and the white goosefoot. At the same time, P. variotii 69 is characterized by seed inhibition of goosefoot germination and the stimulatory effect on the germination of wheat seeds. The strain C. cladosporiodes 12 shown less active and inhibited the germination of white goosefoot seeds. The highest phytotoxic activity was shown by M. vinacea 74. He suppressed the germination of white goosefoot seeds by 50%. The strains Aspergillus ustus 103 and Penicillium acculeatum 122 showed phytotoxic activity only relative to couch-grass. It was shown that the phototoxicity of the studied strains relative to C. vulgaris 190 does not coincide with the phytotoxicity of these strains relative to the weed seeds and wheat, except M. vinacea 74. As it is no findings about phytotoxic effect of strains of C. cladosporiodes and M. vinacea and from the data obtained it might be inferred that the phytotoxic potential of these genus to be the most promising for further researches. Keywords : micromycetes, phytotoxic activity, test-organisms