Seletividade da abobrinha italiana (Cucurbita pepo. L.) a diferentes herbicidas aplicados em pré-emergência de plantas daninhas

Abstract

Italian zucchini is a very important crop for family farming because it is a great form of income for families. This culture has several cultural treatments during its cycle. They are the manual and mechanical control, where at present these types of control are hampered by the high cost of hired labor. Considering the fact of the high cost, this work proposed to study the selectivity of herbicides applied in pre-emergence for the control of weeds in the culture of Italian zucchini (Cucurbita pepo L.). The experiment was carried out at the Universidade Tecnológica Federal do Paraná campus Dois Vizinhos in a randomized block design. Five treatments were used in pre-emergence application: Clomazone, Diclosulam, Mesotrione, 2,4-D + Cletodim and Atrazine + Simazine. The herbicides were applied in two forms: direct and protected. The treatments presented four replicates, in each plot four plants were transplanted. The phytotoxicity, number of true leaves, productivity and plant control were evaluated. The treatments with 2,4-D + Cletodim and Clomazone presented greater selectivity to zucchini culture. The treatments with Diclosulam, Mesotrione and Atrazine + Simazina caused the death of all the plants. The treatment with 2,4-D + Cletodim reduced the number of leaves of the zucchini culture when applied by direct jet. For broadleaf weed species, the treatment with Diclosulam presented higher efficiency while for the narrow leaf the treatment with Mesotrione showed higher efficiency. The productivity for the treatments with 2,4-D + Clethodim and Clomazone were assimilated to those of the control being affected by the application management.