Potencial fisiológico de sementes armazenadas de feijão Caupi Vigna unguiculata (L) Walp tratadas com óleo essencial de cravo da Índia

Abstract

The seeds of cowpea (Vigna uniguiculata (L.) Walp.) Can be treated with essential oil, in order to reduce the attack of insect pests during storage, but it is important that this treatment does not interfere so harmful physiological quality seed. The aim of this study was to evaluate the feasibility and the degree of infestation of cowpea seeds, cv. IPA 206 treated with essential oil of clove and stored for a period of six months at ambient conditions, both in paper and in PET bottles. We used two methods of applying essential oil, a direct method (immersion) at concentrations of 0, 1, 2, 4 and 8%, and an indirect method (fumigation) in the following doses: 0, 5, 10, 15 and 20μL. We used a completely randomized case (DIC) for each type of packaging two experiments were conducted in factorial 5 x 4 (concentrations or dosages and storage periods) with four replications. The following variables were determined: Seedling emergence, speed of emergence index, mean emergence time, emergence rate coefficient, length of the area and root dry mass of the aerial part and root system of the seedling fresh weight part of the area and the root system and electrical conductivity. This was followed by the analysis of variance, treatment means were compared by Tukey test at 5% probability by the program SISVARUFLA, performed the analysis of simple linear correlation at a significance level of 1% (p <0,01), using the statistical program Soc (NTIA / EMBRAPA, 1989), with the exception of water content and degree of infestation. We conclude that the plastic pet bottle got better efficiency, along with the direct method (immersion) that maintained the physiological quality of seeds treated and controlled better insect pests in storage period of six months, except for the concentration 8%. As for the indirect method the highest doses 15 and 20μL, were the most efficient.