Nitrogen use efficiency, accumulation and export of macro and micronutrients related of N-fertilizer doses application in energy cane

Abstract

The biomass use to bioenergy production has been increasing in the last years, mainly with advanced of second generation ethanol. Although this technology is not fully feasible, some breeding programs are developing new cane materials, focusing on production of fiber, called energy cane. These materials have showed a lot of promising, showing high yields of biomass per area. However, there not is information available about plant nutrition and fertilization management for these new energy cane, being used the management of sugarcane conventional, which can be foolhardy, given the high yields of biomass that has been obtained. Thus, the project aims to evaluate the nitrogen use efficiency, the accumulation and export of micro and macronutrintes by energy cane related to N-fertilizer doses application. For this two experiments will be performed in different soil condition. The experiments will be carried on areas with energy cane planted in 2015, where energy cane will be being evaluated for two cycles. It will be evaluated the same energy cane genotype in both sites (sucrose levels from 08 to 12% and fiber content between 20 and 25%). The treatments will be tests in a randomized block design. The four N doses fertilizers will be evaluated: 60, 120, 180 e 300 kg ha-1 as ammonium nitrate, plus the control treatment without N. During the crop cycle, biometric variables of crop will be measured. In the harvest time, samples of plant compartment, e.g. stalk, dry leaves and tops will be collected for physical/chemical characterization (lignin, cellulose, hemicellulose, extractives, ash and N contents) and technology parameters (Pol and fiber). For N-fertilizer effectiveness, microplots with 15N-fertilizer application (180 kg ha-1 of N) will be set up. It is expected the main contributions of this project is to understand the N uptake, N extraction and N export by energy cane, aiming to establish a minimum recommendation for N-fertilizer management, which would be economically viable and environmentally correct. (AU)