Dr. Mark Bernards, Extension Weed Specialist at University of Nebraska discusses Yellow Flash of Soybeans.
Yellow flash is the temporary chlorosis of newly emerging soybean leaves that sometimes occurs following the application of glyphosate to glyphosate-resistant soybean cultivars. Yellow flash is most likely to occur when environmental conditions are warm and moist, favoring rapid soybean growth, and/or when high rates of glyphosate are applied. This temporary chlorosis results from a reduction in chlorophyll content in the affected leaves. Yellow flash has not been shown to affect soybean yield. This presentation will discuss the most likely mechanism by which yellow flash occurs, and discusses the relationship of glyphosate and manganese in soybean growth and yield.