Qualidade fisiológica e potencial de armazenamento de sementes de soja

Abstract

The objective of the present study was to evaluate the physiological quality of soybean seeds during 180 days storage under two environmental conditions. Soybean seeds of the cultivars Brasmax LANÇA IPRO, Brasmax RAIO IPRO, Pioneer 95Y52 and TMG 7062 IPRO, obtained from a Southwestern Paraná producer, were used and homogenized and packed in polypropylene bags. The packages were kept in a climate controlled environment and in an uncontrolled condition, in bags in the producer's warehouse. The experiment was conducted in DIC, with a 2x4x4 factorial scheme (two storage conditions, four storage times and four cultivars), with four replications each. To evaluate the physiological quality of seeds during storage, germination (GERM), germination speed index (IVG), germination speed (VG) and accelerated aging (EA) were analyzed at 0, 60, 120 and 180 days of storage. The data obtained were submitted to ANOVA (p> 0.005) and when the means were significant, they were grouped by the Scott-Knott Test (p>0.05) and regression analysis. For the variable IVG, the cultivars Lança and Pionner, in controlled and uncontrolled environment, presented decreasing linear results, where for each storage day there was a decrease of 0.0651% for the cultivar Lança –NC, 0.0405% for Pioneer. 95Y52 - NC, 0.04055% for Pioneer 95Y52-C and 0.0850% for TMG 7062 – C. The cultivar Lança-C had its results explained by a cubic model, so that the minimum IVG (27.5) occurred at 80 days of storage and the maximum (27.9) at 120 days. For the Raio – NC, Raio-C and TMG 7062 – NC, the results were explained by quadratic models, where the minimum IVG was respectively 152, 22, 135 (22) and 157 (16). days Regarding VG, the environment cultivars Lança – NC, Lança – C, Pioneer 95Y52 – NC and Pioneer 95Y52 – C increased by, respectively, 0.003, 0.004, 0.002 and 0.002 days for germination for each storage day. For the cultivar Raio – NC, the minimum point VG (1.7) was at 41 days of storage and the maximum point (2.2) at 149 days. For the cultivars Raio – C and TMG 7062 – NC and TMG 7262-C, the minimum point VG occurred, respectively, at 22 (1.7), 150 (2.6) and 167 (2.5) days of storage. For germination and accelerated aging, there was a linear decrease onded for each storage day, a decrease of 0.0429 and 0.0741%, respectively. For all studied variables, the Lança-C and Lança-NC environment cultivars presented the best results, so that the lowest indicators were expressed by the environment cultivars Raio-NC, Raio-C, TMG7062-NC and TMG7062-C. It was concluded that the controlled and uncontrolled environments did not present significant differences for all cultivars and variables studied, so that the physiological quality of soybean seeds of Lança, Pioneer 95Y52, Raio and TMG 7062 cultivars decreased during storage. The cultivar Lança was the most storage tolerant, while the cultivars Raio and TMG 7062 were more sensitive to storage, resulting in marked reduction in physiological quality.