K Diagnostics- Soybeans


Symptoms of severe K deficiency in a soybean leaf (left) compared to a leaf from a K-sufficient plant (right). Photo credit: J.J. Volenec	Marginal chlorosis indicative of K-deficiency in soybean. Photo credit: J.J. Volenec	Soybean plants exhibiting K-deficiency symptoms only on lower leaves. This indicates that K is mobile in soybean and is preferentially transported to young tissues when deficiencies exist. Photo credit: J.J. Volenec


Field-scale K deficiency symptoms in soybean (left) compared to K-sufficient plants (right). Photo credit: J.J. Volenec	On low K soils, early growth of soybean and canopy closure is delayed, permitting weeds to flourish. Photo credit: S.M. Brouder	On low K soils, foliar symptoms may not appear uniformly on all plants in the stand. Scouting for K deficiency should involve looking for foliar symptoms on smaller plants that my not be visible when scanning the top of the canopy. Photo credit: S.M. Brouder


Late season, field-scale K deficiency symptoms in soybean (right) compared to K-sufficient plants (left). K-deficiency delays crop maturation and leaf senescence. Photo credit: S.M. Brouder