Controle do oídio da abobrinha com antagonistas e produtos biocompatíveis

Abstract

Efficacy of antagonists and biocompatible products were evaluated for the control of zucchini squash powdery mildew. Seeds of zucchini squash cv. Caserta were sowed in plastic pots of 5L containing 25% of Pinus bark substrate and 75% of soil and keeping in greenhouse without inoculum of powdery mildew. On the stage of one expanded leaf the plants were sprayed with the products and transferred to greenhouse with high inoculum potential. 1) Bacillus subtilis QST 713 [1x109 ufc mL-1, (Serenade®)] on concentration 0, 1, 2 and 4% in milk 10% and on concentration 108, 107, 106 and 0 ufc mL-1 in water; 2) Bacillus pumilus CCMA-661 (4,92 x 109 ufc mL-1) on concentration 0%, 1%, 2% and 4% and liquid medium for Bacillus growth; 3) Bacillus subtilis + Bacillus licheniformis [3,2 109 (Nemix®)] on concentration 108, 107, 106 e 0 ufc/mL in water; 4) Lecanicillium longisporum cepa ESALQ-1300 [1x108 conidia kg-1, (Vertirril®)] on concentration 107, 106 e 105 (ufc mL-1) in milk 10% and in water; 5) Fixed oil of seeds nim (0; 0,5%; 1%; 2% e 4%); 6) Garlic extract (0%; 0,5%; 1%; 2%; 4%; 6%; 8% e 10%); 7) Kaligreen® (0; 0,1; 0,2; 0,4; 0,8, 1,5 e 3,0%); 8) Sodium bicarbonate and potassium bicarbonate (0; 0,5; 1 e 2%); 9) and chitosan (0; 25; 50; 100 e 200mg L-1). The pulverization was carried out once for week during five weeks. The avaliations of disease severity were carried out once for week estimating the percentage of leaf with pathogen. The experimental design was completely randomized with five replicates. With the data was calculated the area under of the disease progress the curve (AUDPC), which were subjected to analysis of variance and average test (p ≤ 0, 05). Bacillus subtilis was efficient to control the disease in concentrations of 4 and 2% and 108 e 107 ufc mL-1; Bacillus pumilus and Lecanicillium longisporum no showed effect on the disease. The biocompatible products kaligreen® at 1,5%, nim oil at 2% and milk 10% effectively controlled powdery mildew in zucchini squash.