Ammonium chloride as an alternative source of nitrogen for sugarcane during two consecutive cycles

Abstract

The objective of this work was to evaluate the effect of the application of ammonium chloride as a nitrogen source for sugarcane (Saccharum sp.) on the development of the crop’s shoot and roots during two consecutive cycles. The experiment was conducted on a Typic Hapludox in the first and second sugarcane ratoons. The treatments consisted of four N doses (50, 100, 150, and 200 kg ha^-1) applied as ammonium chloride (NH₄Cl), besides a control, without the application of N. The increase in the NH₄Cl dose increased in up to three times soil electrical conductivity in the layer of 0.0–0.2 m, with a consequent increase in the concentration of chlorine in leaves. In the second cycle, the contents of chlorine increased in 1,900 mg kg^-1 in the leaf with the application of 200 mg kg^-1 NH₄Cl, when compared with the control. In the first cycle, the application of NH₄Cl doses above 200 kg ha^-1 N promoted a decrease in shoot productivity. In both cycles, there was no effect of the NH₄Cl doses on root dry matter. High doses of NH₄Cl, in consecutive sugarcane cycles, result in a decrease in the productivity of stalks for processing.