Óleo vegetal no controle do míldio e suspensão miceliada aquosa de Agaricus brasiliensis na indução de resistência de videiras cv. Isabel Precoce

Abstract

Viticulture presents some obstacles during the crop cycle, among them is the downy mildew, which presents as a causal agent Plasmopara viticola oomycete, which leads to productivity losses. Based on this fact, the present study aimed to test how alternative control, doses of 0.05, 0.10, 0.20, 0.40, 0.80 and 1.60 mL L?¹ vegetable oil (VO) (Natur`l ® oil, Stoller) as standard treatment and copper sulphate (0,6:0,3:100 (cal: copper sulfate: water) and witness only water treatment on germination and severity of downy mildew in leaf discs under laboratory conditions in vine plants in greenhouse and field; also evaluate the effects of doses of 1 , 5, 10 , 15 and 20% of miceliada aqueous suspension (MAS) Agaricus brasiliensis, acibenzolar -S- methyl (ASM) and only water as a control treatment, on germination , severity of downy mildew in the greenhouse and in the potential to induce the activity of catalase (CAT), peroxidase (POX) and polyphenol oxidase (PPO) in discs taken from leaves of grapevine cv. Isabel Precoce. The doses of VO controlled germination of zoospores of Plasmopara viticola, reduced the area under the disease progress (AUDP) of leaf discs mildew in vines and under conditions of greenhouse curve. Under field conditions, there was no regression with the doses being, however, a dose of 0.1 ml L?¹ AACPD reduced, not differing from treatment with bordeaux mixture. Regarding MAS of Agaricus brasiliensis, we observed a direct effect on the pathogen, but in vivo treatments were not significant in reducing the area under the disease progress (AUDPC) of downy mildew in greenhouse conditions curve. Regarding the enzymatic activities, it was observed that the treatments reduced catalase (CAT), increased peroxidase (POX) and did not affect the polyphenol oxidase (PPO).