EXTRATO AQUOSO DE SHIITAKE NA INDUÇÃO DE RESISTÊNCIA E CONTROLE DE DOENÇAS DE FEIJOEIRO E VIDEIRA

Abstract

The induction of resistance active plant defense mechanisms promoting morphological or physiological changes, after the application of elicitors. Among the elicitors, it has highlighted the use of mushroom extracts. This study verified the potential of the aqueous extract (AE) of Lentinula edodes in induction of resistance, and evaluate whether it can control bean and vine diseases. The treatments for induction of phytoalexins, and peroxidase activity in bean hypocotyl, sorghum mesocotyls and soybean cotyledons application were 0, 1, 5, 10 and 20% AE and acibenzolar-S-methyl (ASM) control. For the field experiment with beans, besides these treatments we used the fungicide Pyraclostrobin as standardcontrol. For the experiment with vine, the control was the Mancozeb fungicide used. In the field experiment with bean were assessed: severity of anthracnose, angular leaf spot and bacterial blight, activity of peroxidase (POX), catalase (CAT) and polyphenoloxidase (PPO) and production components. In vine were carried out in vitro tests with the fungus Elsinoe ampelina, in leaf discs were evaluated the severity and sporulation of Plasmopara viticola, the stakes were assessed the severity of mildew and chlorophyll a fluorescence. The AE in higher concentrations (10 and 20%) have phytoalexin-inducing activity and peroxidases activation, the extract increases the activity of this enzyme to a concentration of 10%. AE in the concentration of 20% did not reduce the severity of anthracnose in beans, however, increased levels of activity of enzymes POX, CAT and PPO, which offset the stress caused by the pathogen attack, increasing the productivity of bean. In vine, AE showed no direct antimicrobial effect on mycelial growth, sporulation and germination Elsinoe ampelina spores or on Plasmopara viticola in leaf discs. The stakes, the concentration of 5% reduced the AUDPC, in addition to increasing the F‟v / F‟m and YII. The AE L. edodes has potential in controlling mildew in grapevine cuttings.