Eficiência de produtos utilizados na agricultura tradicional no manejo de Sitophilus zeamais em milho armazenado

Abstract

One of the major problems in Zea mays conservation is the control of Sitophilus zeamais, insect pest causative of physical damage that can unviable the use of the seeds, needing the application of highly toxic fumigant products. Making feasible the use of alternative products to control weevils and seed conservation con be an accessible protocol for producers, ensuring the production sustainability. In this context, the work aims to research how some products usually used by farmers from 8 de Junho Rural Settlement can assist the control of S. zeamais in stored corn. The diagnosis of the history of the use of alternative treatments for seed conservation was executed through an interview method, using a semi-structured questionnaire. These data were important to determine the bioassays and the experimental design, to assess the efficacy of these methodologies and their influence on physiological quality. Were selected different forms of treatment for application to the stored Zea mays cv. Aztec seeds, to take stock the behavior of S. zeamais The tested treatments were quicklime, chlorine, stove ash, sulfur, dried and ground Petiveria alliacea plant, fresh Petiveria alliacea plant, dried Prunus persica leaf, fresh Prunus persica leaf and control, in the proportion of 5g / kg of seeds. The evaluations were performed at 0, 45, 90 and 135 days of storage, assessing seed moisture, germination, weight of a thousand seeds, infested seed, mortality and insect repellency. A completely randomized design with four replications was used. In the field study, it was verified that most family farmers use Creole seeds and alternative treatments for weevil control. The alternative treatments indicated by family farmers containing quicklime, chlorine powder and stove ash were efficient to conserve corn seeds and did not affect the physiological quality of those. The development of fungi was inhibited during the germination test of both quicklime and chlorine treatments, contributing to the high percentage of germination up to 135 days of storage. The quicklime treatment presented 98% of control after 135 days of storage. The most efficient alternative treatments are among the least cited in the field research. Both guinea and peach leaves treatments were not effective in S. zeamais control. Further studies are recommended for quicklime and chlorine treatments, in order to identify better application dosages and effects on insects and fungi.