Variabilidade espacial de atributos de solo na qualidade fisiológica de sementes de soja tratadas e armazenadas

Abstract

Precision Agriculture facilitates improved management by studying the spatial and temporal variability of soil attributes. Soybean seeds may exhibit distinct quality when produced in different management zones. This study aimed to validate management zones during seed production and identify the variability and spatial distribution of soybean seed physiological quality using geostatistical tools. Management zones were defined based on interpolated maps of soil and vegetation attributes using the Smart Map plugin (SMP) within the QGIS environment. Post-harvest, the variability of physiological seed quality across different management zones was assessed. Germination, accelerated aging, dry weight, emergence, electrical conductivity, and tetrazolium tests were conducted in a completely randomized design. Soil attributes, initial plant stand, and soybean seed productivity validated the management zones. Physiological seed quality varies across the production field, particularly in terms of vigor, thereby enhancing diagnostics through map interpolation. Geostatistics enables determination of the spatial distribution of soybean seed physiological quality in seed production areas, facilitating decision-making regarding harvest zones.

Precision Agriculture is a technique for collecting information on attributes within production areas, which can be expressed in the form of maps defining management zones. While it is not well-established, seeds produced in different management zones may exhibit distinct quality after treatment and prolonged storage. This study aimed to evaluate the physiological quality of soybean seeds produced in different management zones after chemical treatment and storage. Following harvest, seeds from high and low potential zones were treated with Thiamethoxam, Imidacloprid + Thiodicarb, Fludioxonil + Metalaxyl-M, Chlorantraniliprole, Fipronil + Pyraclostrobin + Thiophanate-methyl, Cyantraniliprole, and a control with no treatment. These seeds were then stored for 0, 45, 90, 135, and 180 days in a cold chamber at 15ºC and 55% relative humidity. Seed quality was assessed using tests for germination, dry mass of normal seedlings, germination with pre-conditioning, germination on paper roll + vermiculite, accelerated aging, modified accelerated aging on substrate, electrical conductivity, controlled deterioration, emergence in a growth chamber, vigor index, and tetrazolium. A completely randomized design was employed. Insecticide treatments caused higher phytotoxicity during storage in both management zones. Soybean seeds produced in high potential zones exhibited high physiological quality with less deterioration during storage. Soybean seeds produced in low potential zones, when treated with insecticides and subjected to extended storage periods, showed reduced vigor due to seed deterioration and phytotoxicity.