The role of glyphosate in RR soybean production and seed quality

Abstract

-This study aimed to evaluate the production components and quality of RR soybean seeds (Roundup Ready ® ), after application of increasing rates of gliphosate. Field experiments were conducted in Mandaguari, Paraná, during two seasons. Treatments consisted of five doses of glyphosate. All applications were performed once, between development stages V 4 and V 5. The experiment was arranged in a completely randomized block design, with four replicates. Data were subjected to analysis of variance, and when significant, t-tests and a regression analysis were applied to verify the behavior of the treatments. The physiological and sanitary quality, yield and mass of one thousand seeds were evaluated. The results indicated that seed quality can be adversely affected by glyphosate, and also showed a probable reduction in yield components with increasing rates of application. Keywords:Glycine max, herbicide, transgenic. RESUMO -O presente trabalho teve como objetivo avaliar os componentes de produção e a qualidade das sementes de soja RR, em função da aplicação de doses crescentes de glyphosate. Os experimentos foram instalados em campo, no município de

Performance of transgenic and conventional soybean plants subjected to bioassay for detection of glyphosate tolerant seeds

“…For the sensitive cultivar (UFV16), the small length and lack of secondary roots characterize the halt in seedling development (Cunha et al 2005). Although all cultivars showed reduction in this feature due to the increase in herbicide application rate, the greatest impact was evident in the sensitive seedlings (Albrecht et al 2014). Therefore, along with the lack of secondary roots, sudden reduction in seedling length confirmed identification of herbicide-sensitive seedlings in the germination test, as Cunha et al (2005), Pereira et al (2009a), and Bervald et al (2010) also verified.…”

“…As the tests were conducted, reduction in the length of seedlings due to an increase in herbicide concentration was notable, especially for tolerant cultivars. When glyphosate concentration increases, physiological quality and vigor decline, even in herbicide-tolerant cultivars (Albrecht et al 2014). To confirm this reduction, the seedling length test was conducted (Pereira et al 2009b).…”

“…Adjusted percentage of normal seedlings at the first count and final count of germination, depending on the application rate of the herbicide solution (0, 0.03, 0.06, and 0.12 %) in the germination test, of six soybean cultivars: UFVS Agua Marinha RR (CV1), UFVS Berilo RR (CV2), UFVS Citrino RR (CV3), UFVS Opala RR (CV4), UFVS Turqueza RR (CV5), and UFV-16 (CV6). The data were plotted in comparison to the control group (application rate 0), set at 100%, with the remaining weighted sequence Within each genotype (column), means followed by the same letter do not differ by the Scott-Knott test at 5% probability application rate and time of application, with potential negative effects on vegetative, productive, and seed quality (Albrecht et al 2014). In our study, the highest herbicide concentration used in the germination test (0.12%) impaired the performance of tolerant cultivars only at the level of seedling emergence.…”

“…During the cycle (November/2014 to May/2015), the following measures were taken: height of the plant and first pod height (millimeter ruler), diameter of the hypocotyls (digital caliper rule), dry weight of stems and pods (analytic balance with 0.001 g resolution), number of branches, pods, seeds, and seeds per pod (manual count), and yield per plant (total weight of grains obtained on an analytical balance with 0.001 g resolution, corrected for water content of 13%), according to Albrecht et al (2014).…”

Glyphosate resistant soybean growth and yield affected by glyphosate and phosphate fertilization

“…In Brazil, GR soybean is planted in 32.7 millions of hectares (Celeres, 2017). Although GR soybean is resistant to glyphosate, last years, application of glyphosate resulted in significant crop injury under certain conditions and herbicides formulations (Albrecht et al, 2014a). Recent studies have shown that glyphosate can have phytotoxic effects on soybean by affecting process as secondary metabolism, mineral nutrition, photosynthesis and biomass accumulation (Reddy et al, 2004;Zobiole et al, 2010a;Zobiole et al, 2010b;Zobiole et al, 2011;Zobiole et al, 2012).…”