Qualidade física, fisiológica e sanitária de sementes de milho (Zea mays L.) peliculizadas e armazenadas.

Abstract

Corn is a crop present in various parts of the world, serving as a source of food for humans and animals and as a source of energy. Seeds can be attacked by pests and insects during storage and germination. Several products are used for control and seed coating is a technique that enhances the action of these products. In view of the above, the objective of this research was to determine the physical properties, physiological and sanitary quality of corn seeds filmed during 180 days of storage. In each filming process, a proportion of 1 kg of seeds was used for 10 mL of syrup, corresponding to 1% of the seed weight. Throughout storage, analyzes occurred at times 0, 30, 60, 90, 120, 150, 180 days after coating. The physical characteristics were determined: biometry, porosity, angle of repose, water activity and the water absorption kinetics were performed; in physiological quality, water content, germination test, Germination Speed Index (GVI), dry matter and percentage of infestation; and in sanitary quality, microflora and identification of the main fungi. The experimental design used was completely randomized, in a 14 x 7 + 1 factorial scheme (materials used in coatings plus control x storage periods), each treatment containing four replications. The data were subjected to Analysis of Variance (P f 0.05). For the quantitative factor (storage periods), the data underwent regression in Analysis of Variance to determine the models for each material. For the qualitative factor (materials used in the coatings), the means, when necessary, were compared using the Scott-Knott test (P f 0.05). For statistical analysis, the Assistat 7.7 software and LAB Fit Curve Fitting Software were used. From the coatings, it was possible to conclude that the propolis extract is within the limits required by Brazilian legislation; the applied coatings did not change the physical properties; it was possible to find empirical equations with 2 and 3 parameters to describe the kinetics of water absorption, and the equation proposed by this work, when compared to equations in the literature, was the best to describe the kinetics of water absorption; film coating did not significantly affect the final water content of the seeds; the germination of film-coated seeds reduces with the increase in insect infestation; alternative treatments did not interfere with fungal growth and the fungicide used prevents the emergence or appearance of the main storage fungi in corn seeds.