AMMONIUM CHLORIDE AS NITROGEN SOURCE IN SUGARCANE HARVESTED WITHOUT BURNING

作者：Vieira Michele Xavier^*; Ocheuze Trivelin Paulo Cesar; Junqueira Franco Henrique Coutinho; Otto Rafael; Faroni Carlos Eduardo

来源：Revista Brasileira de Ciencia do Solo, 2010, 34(4): 1165-1174.

• Saccharum spp
• nitrogen fertilization
• ratoon cane

The great difficulty of incorporation of N fertilizers into the "green sugarcane" system causes concern and since urea is the most commonly used source, there is the risk of loosing NH(3) through volatilization. For this reason, a field experiment was undertaken (in a Hapludox Typic) with the objective of evaluating the agronomic efficiency of ammonium chloride on stubble of the second ratoon (SP89 1115), as well as its residual effect on the subsequent cycle (third ratoon). The experimental design was randomized blocks with four replications. Treatments consisted of three N rates (60, 120 and 180 kg ha(-1) N) in the form of NH(4)Cl, in addition to a control treatment without the addition of N fertilizer. The ratoon cane of the second cutting was harvested in November 2006 and the treatments were applied in December 2006. The second ratoon was harvested mechanically in November 2007 and in December 2007, 450 kg ha(-1) of the NPK mixture 20-05-19 was applied, providing 90, 22 and 86 kg ha(-1) N, P(2)O(5) and K(2)O, respectively, for the purpose of evaluating the effect of residual-N from the treatments implanted in December 2006. An increase in the rates of N-NH(4)Cl had a positive effect on the leaf concentrations of P, Mg and S. Stalk yield (MSS - Mg ha(-1) of sugarcane stalks) and sugar (MSH - Mg ha(-1) of sucrose) in the November 2006 harvest responded linearly to the increase of N doses in the form of NH(4)Cl. In relation to the effect of residual-N in the 2007/2008 harvest, it was observed, in general, that the concentrations of macronutrients in the sugarcane leaf +1 were within the range considered adequate in the state of Sao Paulo, Brazil. The residual-N of the NH(4)Cl doses resulted in a significant reduction in stalk (MSS) and sugar (MSH) production. It may be concluded that the NH(4)Cl source at a dose of 120 kg ha(-1) N in ratoon fertilization of the second cutting was agronomically efficient, presenting, however, less efficiency of residual-N in the subsequent cycle.

• 出版日期2010-8