Resumo

OROZCO-VIDAL, Jorge Arnaldo et al. Nitrogen sources on growth and biomass production in maize. Rev. Mex. Cienc. Agríc [online]. 2016, vol.7, n.1, pp.185-194. ISSN 2007-0934.

The objective of this research was to determine the dynamics of growth and efficiency of biomass production and distribution in a hybrid of forage maize (HT9019Y) fertilized with two nitrogen sources (traditional and slow release) from vegetative and reproductive samples made in different growth stages. Sowing was done in the spring-summer 2014. The sources of nitrogen were distributed in an experimental design of randomized blocks with eight repetitions. In four different dates (20, 40, 60 and 80 dds) samples where two plants were collected by experimental data unit for leaf area, total dry weight and dry weight of vegetative and fruitful organs were performed. Rates of growth and crop growth rate (CGR), net assimilation rate (NAR), leaf area index (LAI), leaf area ratio (RAF), specific leaf area (SLA) and leaf weight ratio (RPF) were estimated with the data. The results show that there was a significant statistical difference in indicators of the magnitude of the photosynthetic apparatus (RAF and AFE) between nitrogen sources studied, the best results with the source of slow release nitrogen (Nitrogen Ecology Technology). As well as to the production rate differences 262.4 g m-2 to use the nitrogen source Entec, resulting in the final stages of growth increased speed of their metabolic processes and greater photosynthetic efficiency to obtain a TCC of 142.00 and Such of 48.75 gm-2 d-1, respectively.

Palavras-chave : Zea mays L.; TAN; IAF; photoassimilates; slow release nitrogen.