Amino Acid Application Can Be an Alternative to Prevent Glyphosate Injury in Glyphosate-Resistant Soybeans

Abstract

2 Glyphosate-resistant (GR) soybeans have continuously increased; however, this expansion significantly increased the use of glyphosate and therefore, in some cases, has resulted in injury symptoms observed in GR soybean, known as "yellow flashing". Previous reports of interference of glyphosate with nutrient availability and utilization by GR soybean may be linked to this injury symptom. Also, because glyphosate interferes with amino acid synthesis, supplementation with exogenous amino acids may help GR soybean recover from adverse effects of glyphosate. Therefore, an experiment was designed to evaluate different amino acid concentrations. Near-isogenic and GR soybean varieties were grown in the greenhouse in two soils with and without glyphosate at different rates and amino acids were foliarly applied with and without glyphosate. In general, the photosynthetic variables, nutrient contents, and shoot and root dry biomass parameters were affected by glyphosate, however, use of amino acid formulations suppressed harmful effects of glyphosate on these parameters.

Lack of transgene and glyphosate effects on yield, and mineral and amino acid content of glyphosate‐resistant soybean

“…Overall, our results discount previous claims of glyphosate effects on mineral nutrition of GR crops . These previous papers have claimed effects on Mn, Mg and Fe in particular, and have related purported effects of glyphosate on these minerals to claims of increased susceptibility to crop disease, chlorosis, and decreases in growth and/or yield .…”

“…Overall, our results discount previous claims of glyphosate effects on mineral nutrition of GR crops. [4][5][6][7][8][9][10][11][12][13][14][15] These previous papers have claimed effects on Mn, Mg and Fe in particular, and have related purported effects of glyphosate on these minerals to claims of increased susceptibility to crop disease, 4,8,9 chlorosis, 7,10 and decreases in growth and/or yield. 7,15 Although we found some statistically significant differences for some of the minerals, there were no consistent effects between years, treatments and plant tissues.…”

“…Similar adoption rates have occurred in other countries such as Argentina and Brazil after these crops were approved for production. Although yields of cotton, maize and soybean in the USA have continued upward since these GR crops were introduced, some have claimed that glyphosate causes deficiencies in cationic minerals in GR crops, due to either the chelation of glyphosate with divalent metal cations and/or toxic effects on rhizosphere microbes involved in the assimilation of these nutrients from soil . Others have found no effects of glyphosate on mineral content in GR crops .…”

“…Although yields of cotton, maize and soybean in the USA have continued upward since these GR crops were introduced, 2,3 some have claimed that glyphosate causes deficiencies in cationic minerals in GR crops, due to either the chelation of glyphosate with divalent metal cations and/or toxic effects on rhizosphere microbes involved in the assimilation of these nutrients from soil. [4][5][6][7][8][9][10][11][12][13][14][15] Others have found no effects of glyphosate on mineral content in GR crops. [16][17][18][19][20][21][22][23][24][25][26][27] In a review of most of this literature, 2 the authors concluded that the strongest available evidence in the literature supported the view that glyphosate does not significantly affect mineral nutrition in GR crops.…”

Glyphosate Stimulates the Accumulation of N-Compounds, Grain Yield and Seed Vigor in Glyphosate-Resistant Soybean

“…Literature data show that glyphosate causes visual injury symptoms on GR soybean plants (Zobiole et al, 2012), altering the nutritional status, mainly, with symptoms of Zn, Fe and Mn deficiency (Johal & Huber, 2009), reduction of photosynthetic efficiency and water use (Zobiole, 2010a(Zobiole, , 2010b. However, in some non-transgenic plants subjected to low glyphosate doses, the stimulant effect is frequently observed (Cedergreen, 2008;Dalley & Richard, 2010).…”