Foliar Nitrogen fertilization of wheat in Southwestern Buenos Aires

Foliar nitrogen fertilization of wheat in Southwestern Buenos Aires

M.R. Landriscini, J.M. Martínez, J.A. Galantini

Abstract

In the semiarid and subhumid Pampean region, foliar nitrogen (N) application to wheat at anthesis stage coincides with an erratic rainfall period, which defines yield and quality. The objectivesof the study were to evaluate the effect of foliar N application at anthesis on wheat grain yield and quality in the Southwestern of Buenos Aires Province, an area characterized by variations in climate and soil fertility, and to apply the principal component analysis (ACP) in all variables. A total of 30 experiments were conducted from 2004 to 2012 in the Southwestern. Nitrogen rates of 0, 25, 50 and 100 kg N ha^-1were applied at sowing and 25 kg ha^-1 at anthesis. Water availability to the crop was variable in the study period, which caused significant yield variations. The ANOVA for all the experiments, showed no significant differences for N at sowing or at anthesis, but it indicated a protein increase in 25 of the 30 experiments. In all trials yield from the control treatment ranged from 1784 to 2600 kg ha^-1and N foliar application response from 145 to 1273 kg ha^-1. The grain protein content, which averaged 132 g kg^-1, increased 11% with N fertilization at anthesis. Low and poorly distributed rainfall limited yield and foliar N response. Nitrogen rates at sowing that produced the maximum response to foliar application ranged from 0 to 100 kg N ha^-1. The most influential variables in ACP were the rainfall of September, October and November, dry matter at Z60,soil water content at sowing and N availability. The yield was estimated with 72 % confidence and protein with 59%. In these environments, foliar N application resulted in variable grain yield buy it proved to be a useful practice for enhancing protein content.

Key words: Nitrogen, Anthesis, Yield, Grain Quality

In Landriscini M.R., J.M. Martínez, J.A. Galantini. 2015. Fertilización foliar con nitrógeno en trigo en el sudoeste bonaerense. Ciencia del Suelo (In press)