Seasonal evaluation of colored upland cotton BRS Rubi nutritional status

Abstract

The knowledge of the plants nutritional status is important to evaluate the production potential and to search for a balance between nutrients. Studies using foliar diagnosis have been very efficient, because the plant is the soil nutrient extractor itself. Therefore, the aim of this study was to determine the nutritional status and the redistribution of nutrients in plants of the colored upland cotton cultivar BRS Rubi by foliar analysis tool. The experiment was conducted in São Pedro community, Itaporanga County, Paraíba State, Brazil, located in the Sertão Paraibano mesoregion, from October 2009 to January 2010. The experimental design was a randomized block with four replications in a split plot scheme, where plots were represented by two periods of sampling leaves (at 58 and 107 days after planting - DAP) and the subplots by six levels of organic adubation in the form of increasing doses of bovine manure (0; 2.5; 5; 10; 20 and 40 t ha-1). Only the N and K determined at 58 and 107 days after planting, presented significant and greater redistribution compared to the other macronutrients analyzed. For the micronutrients analyzed, no significant difference between the evaluation periods was observed.