Extrato etanólico obtido do composto exaurido de agaricus blazei no crescimento, esporulação e germinação in vitro de corynespora cassiicola e na indução da enzima peroxidase em plantas de pepino “japonês”

Abstract

The extracts of basidiocarps of Agaricus blazei have been studied in the resistance induction in plants to fungal diseases in different pathosystems, as in the cucumber culture. Besides the basidiocarps, the own cultivation’s substratum can be used, since most of the producers of A. blazei reuse neither the residues of the discarded substratum after the crop of the mushrooms nor the substratum inoculated that didn't produce satisfactorily. The purpose of the present work was studied the effects of ethanolic extract obtained of compost of Agaricus blazei in environment in vitro of corynepora cassicola and induction of enzyme peroxidase in cucumber plants. In the tests of micelial growth, esporulation and germination, using aqueous solutions in concentrations of 0; 0,5; 5; 50; 500 and 5000 ppm, it was verified that none of the incorporated concentrations in the medium BDA, inhibited the growth and the esporulation of the C. cassiicola, what suggests the non existence of fungicidal effect. In the experiment with cucumber plants a significant increase of the local activity of peroxidase was verified (2a leaf), in doses of 5 and 0,5 ppm. After the induction interval of four days, before the inoculation with C. cassiicola, the 0,5 ppm concentration showed significant differences in relation to the other doses. Based on the obtained results and for the fact of the abscense of direct antimicrobial activity on the pathogen in the tested concentrations, the ethanolic extract from the substratum of cultivation of A. blazei can be seen as a potential biotic elicitor of resistance in plants.