yellow flash
n.— «A Purdue University agronomist said that many farmers over the last several years have observed a mid-season yellowing of their soybeans, commonly called “yellow flash,” which is caused by a manganese deficiency.» —“Manganese deficiency in soybeans? Experts advise foliar application” in West Lafayette, Indiana Media Newswire April 21, 2009. (source: Double-Tongued Dictionary)