Rapid Growth Syndrome

While not a disease or a true pest threat, RGS can result in significant cosmetic damage and crop unevenness raising concern in otherwise healthy fields.  Rapid Growth Syndrome is a physiological condition in corn, often observed during the V5 to V8 stages, characterized by twisted, crinkled, or rolled upper leaves. These symptoms are caused by rapid elongation of the stalk, which forces tightly wrapped leaf whorls to expand before they are ready, resulting in physical distortion

The causes of RGS are cool, cloudy weather followed by a sudden increase in heat and sunlight, ample soil moisture supporting a surge in vegetative growth, and genetic predisposition with some hybrids more susceptible than others. Symptoms of RGS include rolled upper leaves, yellowing of the whorl where trapped leaves are exposed, and in extreme cases full canopy twisting. Despite the dramatic appearance the stalks often recover fully within 5 to 10 days. 

There is no treatment or product that reverses RGS but growers can take comfort that it does not impact yield potential in most cases. Plants usually recover quickly as new leaves emerge. Rapid growth syndrome can be alarming at first glance but rest assured, it’s a temporary condition. With the right genetics and agronomic planning your crop will power through and perform to its full potential.