Tratamento químico, diferentes condições e períodos de armazenamento na qualidade fisiológica de sementes de arroz

Abstract

The seed is considered as the main input in agriculture, which must have physiological quality to reach its maximum productive potential. In addition, the germination test is one of the parameters to analyze the viability and represent the emergence in the field when sowing is carried out in ideal soil conditions. Therefore, this work aims to evaluate the germination percentage of rice seeds (Oryza sativa) cultivar IRGA 431 CL from the year 2021 with and without seed treatment, stored for different periods in prototypes of vertical silos and big bags. The experiment was installed in the Post Harvest Laboratory of the Federal University of Pampa - Campus Alegrete, where they remained for 6 (six) months. The germination tests were mounted every 30 (thirty) days throughout the storage period, in the laboratory of Agroindustrial Cooperative Alegrete LTDA. The design to be used was completely randomized (DIC), three-factor (2 x 2 x 6) for the factors seed treatment levels, storage type and storage period. There are twenty-four treatments, each with four repetitions, totaling ninety-six experimental units + initial analysis + final analysis (composed of 4 repetitions for the use or not of seed treatment). The factors were composed of two seed treatments (T1: with seed treatment; T2: without seed treatment), two storage levels (A1: mini silo prototype; A2: big bag prototype) and six different storage periods (P1: thirty days; P2: sixty days; P3: ninety days; P4: one hundred and twenty days; P5: one hundred and fifty days and P6: one hundred and eighty days). After setting up the germination tests, the counts were performed on the fifth and fourteenth day after insertion into the incubator. The results indicated that there was a reduction in the percentage of vigor and germination throughout the storage period, under the presence of seed treatment, regardless of the type of storage used. Storage in waterproof packaging is less harmful to the physiological quality of the seeds, and the percentage of germination was greater than 80% in all treatments, in accordance with Normative Instruction No. 45 of 2013 for commercialization. From the first 30 days, the portion of treated seeds started to have a decrease in the physiological quality of rice seeds.