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

Abstract

The adoption of genetically modified soybean cultivars is increasing annually around the world, which indicates the excellence of these genotypes. For soybean breeding, the use of such cultivars in a backcross program relies on the ability to detect the transgenic trait. The germination test in a moistened substrate with glyphosate is effective and of low cost, however, wonders whether this is a non-destructive method to check cultivars. The objective of this study was to apply a bioassay for detection of herbicide-tolerant seeds and to evaluate the vegetative and productive development of the plants. It was observed that both glyphosate-tolerant and glyphosate-sensitive plants were affected in the initial stages of development in accordance with the herbicide application rate. However, whereas tolerant plants fully recover both in vegetative growth and production during the cycle, sensitive plants recover partially, producing smaller plants with lower yield as a consequence of the herbicide application rate.

Influence of genotype-environment interaction on soybean (Glycine max L.) genetic divergence under semiarid conditions

“…The results of our experiments showed that the data obtained for the various characteristics were within the range observed for soybeans, with the lowest value observed for oil content (4.28%), and the highest for dry matter (51.18%). With the exception of dry matter, the estimated values of the evaluated characteristics were within the CV range observed for soybean (7,11,19,21,26). The highest selective accuracy was verified for flowering and maturation and the lowest for dry matter, conforming to the lowest precision observed for the latter characteristic.…”

Seed reserve mobilization and seedling morphology in a bioassay for the detection of genetically modified soybean

“…Analyzing the first and the final counts of germination data (Table 1), it was notable that both herbicide solutions (0.06, and 0.12 %) inhibited the development of normal seedlings by the genotypes, like observed also by Bervald et al (2010) and Pereira et al, (2018). In the case of glyphosate-tolerant cultivars, the highest concentration of the herbicide (0.12 %) affected the first and the final counts of germination, as observed by Pereira et al, (2018), however, the glyphosate-tolerant seedlings developed secondary roots, while the sensitive ones did not (Figure 1). The absence of secondary roots in glyphosate-sensitive seedlings is a striking feature of this bioassay (BERVALD et al, 2010;MELO;FAGIOLI;SÁ, 2013;PÁDUA et al, 2012).…”

“…According to Funguetto et al (2004);Heinz;Viegas Neto and Valente (2011);Pereira et al 2018;and Tillmann and West (2004) the length reductions are more striking for glyphosate-sensitive genotypes. In our study, this was a notable occurrence.…”

“…Cultivars that carry the CP4 EPSPS gene are glyphosate-tolerant (NAKATANI et al, 2014). When these cultivars are submitted to germination in substrate moistened with glyphosate solutions, secondary roots are present, but in length, number, and volume smaller than in the control treatment, as observed by Pereira et al, (2018); in fact, the herbicide affects the development of sensitive and tolerant seedlings at different levels of intensity. 17,4 * Averages followed by the same letter, uppercase in the horizontal and lowercase in the vertical, do not differ, at the level of 5 % probability.…”

Genotyping and molecular analysis of transgenic sequences in chrysanthemum (Chrysanthemum X morifolium Ramat)

“…Differentiation methods based on morphological characters, have the disadvantage of being laborious, time-consuming and influenced by the environment (Shao et al 2010, Orroño andVesprini 2018); in other cases, the expression of transgenes is analyzed directly in seedlings (Pereira et al 2018). An alternative is the characterization with molecular markers.…”