QUALIDADE FISIOLÓGICA DE SEMENTES DE MILHO SUBMETIDAS AO TEMPO DE TRATAMENTO QUÍMICO E PERÍODOS DE ARMAZENAMENTO

Abstract

Corn is one of the most important agricultural crops in the world and the use of high quality seeds is essential for productive success. Thus, it is necessary to evaluate seed deterioration as a function of storage time in order to extend the shelf life of the seed lot and ensure that seeds of high physiological quality are able to tolerate adverse factors when sown in the field. The chemical treatment of seeds is used in order to control pathogens and improve the physiological quality of seeds under storage. Knowing this, the objective of this work was to evaluate the physiological quality of corn seeds submitted to periods of storage after the chemical treatment time. The experiment was carried out at the Seed Processing Unit of the company Limagrain Brasil S.A. Physiological quality analyzes were carried out at the Seed Analysis Laboratory and seedling emergence area in the field at Limagrain Brasil. The experimental design was in randomized blocks in a 4 x 4 split-plot scheme, with four replications. The plot consisted of four time intervals after storage and the subplots for four evaluation periods after new storage, totaling 16 treatments and 64 experimental units. A single hybrid maize cultivar was used. After 30 days of storage, the samples were removed and conditioned at room temperature. The working samples were industrially treated with C4 during the collection period (0, 24, 48 and 72 hours after removal from refrigeration). Then, they were again stored at 10 ºC and evaluated at 0, 30, 60 and 90 days after treatment with C4. The cold vigor test, germination and emergence in the field were carried out. Data were subjected to analysis of variance and Tukey's test at a 5% significance level. There was no interaction between the studied factors (P>0.05) for the analyzed variables. When evaluated separately, only the storage time of 90 days reduced (P<0.05) field emergence.