Simulation of wheat biomass yield by thermal time, rainfall and nitrogen

Simulação da produtividade de biomassa do trigo pela soma térmica, precipitação e nitrogênio

ABSTRACT

Wheat biomass yield focused on the production of quality silage is dependent on rainfall, temperature and nitrogen (N). The objective of the study was to validate the use of rainfall, thermal time and N as potential variables for the composition of the multiple linear regression model and simulation of wheat biomass yield for silage production under N supply conditions during the cycle, in the systems of succession. The study was conducted in 2012, 2013 and 2014, in randomized blocks with four replicates in 4 x 3 factorial, for N-fertilizer doses (0, 30, 60, 120 kg ha^-1) and forms of N supply [single application (100%) in the stage V₃ (third expanded leaf); split application (70%/30%) in the stages V₃/V₆ (third and sixth expanded leaves); split application (70%/30%) in the stages V₃/E (third expanded leaf and beginning of grain filling)], respectively, in the systems soybean/wheat and maize/wheat. Rainfall and N are potential variables in the composition of the multiple linear regression model. Multiple linear regression models are efficient in the simulation of wheat biomass yield for silage under the N supply conditions during the cycle in the succession systems.

Key words: Triticum aestivum; N dose; split N application; residual N; silage