Suppressing pecan aphid populations using potassium nitrate plus surfactant sprays

A 4-year field study on pecan [Carya illinoinensis (Wangenh.) K. Koch] provided indirect support of the supposition held by some U.S. pecan growers that air-blast foliar sprays of potassium nitrate (KNO 3 ) plus surfactant enhances nut yield. While these treatments did not measurably influence yield components, foliar K nutrition, or net photosynthesis, they did suppress yellow-type aphid populations. While air-blast sprays of water alone suppressed aphid populations, the inclusion of KNO 3 plus surfactant provided an additional level of suppression.