Grain productivity and nitrogen fractions of maize under organic fertilization in semiarid region Brazil

The objective of this study was to evaluate the effects of different organic fertilization treatments on maize grain productivity and nitrogen fractions in semi-arid NE Brazil. The experimental plots were established in a Entissol in randomized blocks in a factorial design (2 x 3) + 2 that included two methods of fertilizer application (surface applied or incorporated) and three types of organic fertilization (15 t.ha(-1) of animal manure, 15 t.ha(-1) of Gliricidia sepium prunings, 15 t.ha(-1) of Croton sonderianus prunings) and control plots without fertilization). The method of application and the three types of organic fertilizer had different effects on maize grain productivity and nutrition. For example, all types of organic fertilizers, when surface applied, significantly increased maize grain productivity and N concentration. Maize leaf N content was greater after surface application of G. sepium prunings. Surface application of manure increased leaf P concentration, but leaf K was greater after incorporation of C. sonderianus prunings. Maize leaf N fractions were inversely related to grain productivity.