The study of herbicide dynamics in the soil and their interaction with the components of the environment makes it possible to ensure the selectivity of crops and the agronomical efficiency. The aim of this research was to evaluate the influence of soil physicochemical properties on the emergence and growth of soybean, with pre-emergence application of various saflufenacil rates. An experiment was carried out in a greenhouse with a completely randomized design, testing different soil types containing “Erechim”, “Santa Maria” and “Eldorado do Sul”, at different saflufenacil rates: 0, 12.5, 25, 50, 100, 200, 400 g a.i. · ha–1. The application was performed 1 day after soybean sowing, and analyzed variables were: the phytotoxicity emergence of seedlings, dry mass and height of the soybean. The saflufenacil effective dose of 50% response in soybean (ED50) and the characteristics of the soils showed that the soil contained clay and sand which were the components most related to the saflufenacil availability to the plants. A lower ED50 by phytotoxicity to the soybean was found in soil with lower and greater content of clay and sand, respectively. The physicochemical properties of soil influenced the saflufenacil activity, having greater potential of injury to soybean in the soil from Eldorado do Sul, due to its clay and sand content.

Metal ions can modify plant metabolism and change the level of biologically active components. In the present study, the impact of short-term exposure to strontium on the accumulation of the metal as well as the content of isoflavones in soybean sprouts was investigated.

The seeds were germinated in hydroponics with 0, 1, 1.5, 2.5, 5.0, or 10.0 mM of Sr for 72 hours. The content of strontium was assessed using flame atomic absorption spectrometry and the amount of isoflavones was determined with high performance liquid chromatography. Dose-dependent accumulation of Sr and a linear correlation between the Sr concentration in the growth medium and the content of the element in the plant samples were observed. The largest changes in the isoflavone content, compared to the control, were noted in soy sprouts germinated in the presence of 5 and 10 mM of strontium. Daidzin, genistin, malonyldaidzin, and malonylgenistin were the dominant isoflavones and their content increased by approx. 28, 44, 34, and 47%, respectively, compared to the control. Low amounts of aglycones were found; moreover, their content decreased by ca. 19–30%. Our research can be important for obtaining a natural product enhanced with strontium and isoflavones, which contribute to prevention of osteoporosis associated with endogenous oestrogen deficits.

The “second generation” of glyphosate-tolerant soybean (GT2 soybean) was developed through a different technique of insertion of the glyphosate-insensitive EPSPs gene, in comparison with “first generation” of glyphosate-tolerant soybean. However, there is not enough information available about glyphosate selectivity in GT2 soybean and the effects on the quality of seeds produced. The aim of this study was to evaluate tolerance to glyphosate and seed quality of soybean cultivar NS 6700 IPRO (GT2) with cp4-EPSPs and cry1Ac genes, after application at post-emergence (V4). The experiment was conducted in a randomized block design with four replicates and seven treatments, or rates of glyphosate (0; 720; 1,440; 2,160; 2,880; 3,600; 4,320 g of acid equivalent − a.e. · ha−1). Assessments were performed for crop injury, SPAD index and variables related to agronomic performance and seed quality. A complementary trial with the same cultivar and treatments in a greenhouse was conducted in a completely randomized design with four replications. Data analysis indicated no significant effect of glyphosate on V4 on agronomic performance and physiological quality of seeds, for two growing seasons. The soybean cultivar NS 6700 IPRO (GT2), with cp4-EPSPs and cry1Ac genes, was tolerant to glyphosate up to the maximum rate applied (4,320 g a.e. · ha−1) at post-emergence (V4). The quality of soybean seeds was not affected by glyphosate up to the maximum rate applied (4,320 g a.e. · ha−1) at post-emergence (V4).

According to the SRES A1B climate change scenario, by the end of the 21st century temperature in Poland will increase by 2–4°C, no increase in precipitation totals is predicted. This will rise crop irrigation needs and necessity to develop irrigation systems. Due to increase in temperature and needs of sustainable agriculture development some changes in crop growing structure will occur. An increase interest in high protein crops cultivation has been noted last years and further extension of these acreage is foreseen. Identifying the future water needs of these plants is crucial for planning and implementing sustainable agricultural production. In the study, the impact of projected air temperature changes on soybean water needs, one of the most valuable high-protein crops, in 2021–2050 in the Kuyavia region in Poland was analysed. The calculations based on meteorological data collected in 1981–2010 were considered as the reference period. Potential evapotranspiration was adopted as a measure of crop water requirements. The potential evapotranspiration was estimated using the Penman–Monteith method and crop coefficient. Based on these estimations, it was found that in the forecast years the soybean water needs will increase by 5% in the growing period (from 21 April to 10 September), and by 8% in June–August. The highest monthly soybean water needs increase (by 15%) may occur in August. The predicted climate changes and the increase in the arable crops water requirements, may contribute to an increase in the irrigated area in the Kuyavia region and necessity of rational management of water resources.

The aim of the present work was to evaluate the selectivity of nicosulfuron, alone and in combinations, applied in post-emergence (V4) of glyphosate and sulfonylurea tolerant (RR/STS) soybean. The experiments were conducted in 2015/16 and 2016/17, in Piracicaba – state of São Paulo (SP). In 2016/17, the experiment was also conducted in Palotina – state of Paraná (PR). The experiment was a randomized block design, with four repetitions and 16 treatments, with combinations of nicosulfuron, glyphosate, chlorimuron, sulfometuron and cloransulam, applied alone or in tank mixture. Crop injury and variables related to agronomic performance were evaluated. Data were subjected to analysis of variance and treatment means were compared by the Tukey test. The results obtained are significant in the positioning of herbicides in RR/STS soybean, since in the five experiments, all the treatments were selective, except for glyphosate + sulfometuron which reduced the yield of a cultivar (CD 2630 RR/STS) in the 2015/16 season.