ABSTRACT
Alternaria leaf spot caused by the fungus Alternaria solani is one of the main and most frequent diseases that affect tomato crop. It manifests on stalks, stems and especially on leaves, at high severity. It causes defoliation and can also induce infections in the fruits, making them inappropriate for commercialization. To control the disease, synthetic defensives are still the most used products. With the aim of lowering the toxicity to the environment and to the human health, the search for alternative products has emerged. The objective of this study was to evaluate the effect of plant extracts for the control of Alternaria solani in tomato culture: in vitro and in vivo. The experiment was performed in two steps: 1- in vivo (in a greenhouse under hydroponic system) and 2- in vitro (in the laboratory). The treatments used in the first step were: 1- Control (no application); 2- “Assa Peixe” extract; 3- “Aroeirinha” extract; 4- “Pata de Vaca do Cerrado” extract; 5- “Murici” extract, all of which were used at the proportion of 10% extract diluted with water and another control to which a fungicide (Pyraclostrobin) was applied. Experimental design was in randomized blocks with four replicates. In the second step, the experiment was carried out in completely randomized design, with the same treatments used in the first step, except for the commercial treatment. “Aroeirinha” and “Assa Peixe” extracts provided Alternaria leaf spot control in tomato plants in the in vivo experiment. However, for the in vitro experiment, “Murici” and “Aroeirinha” extracts decreased the mycelial growth of the fungus.
Keywords
Alternative control; Solanum lycopersicum; Alternaria solani; plant extract
