Potencial de armazenamento e causas da perda de vigor de sementes salvas de soja na safra 2022/2023

Abstract

The proper establishment of the crop and higher productivity are directly linked to the use of high-quality seeds, whose factors contributing to this include high germination and vigor percentages, healthiness, and physical and genetic purity. In the productive context of soybean cultivation, producers often choose to save their seeds and use them in the next harvest, as an alternative to reduce costs. In the Alto Uruguai Gaúcho region, this practice is common. Therefore, the aim of this study was to evaluate the quality of saved soybean seeds in the Alto Uruguai Gaúcho region of the 2022/2023 harvest, by determining post-harvest and pre-sowing germination and vigor, identifying causes of vigor reduction in the seeds, and assessing the storage potential of the lots for sowing in the following season. Thirteen lots of saved soybean seeds from the municipalities of Cruzaltense, Entre Rios do Sul, and São Valentim were used. The experiments were conducted at the Federal University of Fronteira Sul, Erechim Campus, using a completely randomized design. The following tests were conducted: germination, electrical conductivity, tetrazolium (vigor, viability, and identification of causes of vigor loss - mechanical damage, moisture, and bugs), sodium hypochlorite test, and accelerated aging at 48 and 72 hours (determination of storage potential). For germination and vigor tests, only lot 1 showed germination similar to 80%, the minimum established value. The lots exhibited low vigor. Among mechanical damage, moisture, and bug damage, mechanical damage was the main cause of seed vigor reduction. Thus, few lots of saved seeds from the Alto Uruguai Gaúcho region have physiological quality for sowing purposes. Only 15% of the thirteen lots of saved soybean seeds should be stored for sowing in the next harvest.