Extrato de gengibre como alternativa para o controle de tripes (Thrips tabaci) em alface hidropônica

Abstract

The use of medical plants with insecticidal properties in the form of plant extracts is an ancient practice in agriculture. The ginger is, among the plants used, a species that has insecticidal properties and it’s also a suitable alternative for replacing the use of pesticides. Considering that, this study aims to evaluate the use of ginger extract (Zingiber officinale Roscoe) in hydroponic lettuce, as a way of managing thripes (Thrips tabaci). The experiment was conducted in a randomized blocks design, with 5 treatments and 4 replications. The treatments consisted in concentrations of 0%, 20%, 40%, 60% and 80% of ginger aqueous extract, in the proportion of weight/volume. Each experimental piece got an adhesive trap in its central part for capturing adult insects. After 45 days of seeding, the ginger extract was applied to the lettuce at every seven days, totalizing three applications. The thripes populational growth was monitored from the calculation on the traps once in a week, until the harvest, and it was evaluated the height of the fresh substance, the shoot height, and the incidence of direct crop damage, through pest feeding. Regarding the thripes’ monitoring, it was noted a high populational level on the beginning of the vegetative development, promoting a high incidence pressure of the insect-pest on the lettuce cultivation. It wasn’t stated any relevant difference between the treatments during the evaluation of the plant development, height and fresh substance. When it comes to the analysis of direct crop damage, the treatment with an 80% concentration height/volume showed the lowest levels of plants with symptoms of leaf curling and tanning, showing that the highest the concentration of the solution, the lower was the insect feeding. Hence, the use of ginger extract in hydroponic lettuce it’s a promising alternative for reducing the thripes’ feeding in lettuce, reducing the virus transmission.