Crescimento e produção de cana-de-açúcar cultivada sob sistema irrigado.

Abstract

The cultivation of sugarcane in the Northeast of Brazil has been conducted since the colonization of the country, it is very important to the local economy. Despite being a secular culture in the region, there is still great demand for technologies that address the problem of low productivity. Among the technologies needed for irrigation and genetics in the region to obtain new varieties. Under conditions of water scarcity in the Northeast, the practice of irrigation is essential. The aim of this study is to evaluate the behavior of improved varieties of sugarcane under different irrigation for agronomic and technological characteristics under local conditions in the Northeast of the State of Pernambuco. The experiment was conducted on Usina Central Olho D’Água in the municipality of Camutanga - PE. The experimental design was a randomized tracks, split plots (5 x 3), being used in the plots five levels of ETC, 10%, 50%, 75%, 100% and 115% of ETC. Subplots was used the three most widely planted variety in the plant: RB92579, RB867515 VAT90-212, with four replications. Irrigation was by sprinkling. Irrigation management was monitored using the reference potential evapotranspiration calculated using the Hargreaves methodology. Plants were harvested at 10 months old cane plant. The agronomic variables evaluated were: number of stems per meter, plant height, agricultural productivity (t ha-1), Productivity in sugar (ATR.t ha-1) and analysis technology: Pol% cane, fiber, Purity and ATR. Data were subjected to analysis of variance and means were compared by Tukey test, P <0.01 or <0.05 for varieties, and regression for irrigation. As for agronomic evaluation, variety RB92579 showed higher plant height with 1351 mm. The variety RB92579 had the highest number of tillers in total irrigation 1529.11 mm, the variety RB867515 was more efficient in water use at smallest 424.55 mm depths. Increasing agricultural productivity grew linearly with increasing water depths. The efficiency of water use decreased with increased irrigation.