Efficiency of phosphate sources and filter cake in sugarcane

• Grant number: 14/06908-7
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: June 01, 2014
• End date: May 31, 2015
• Field of knowledge: Agronomical Sciences - Agronomy - Soil Science
• Principal Investigator: Paulo Sergio Pavinato
• Grantee: Aline de Camargo Santos
• Host Institution: Escola Superior de Agricultura Luiz de Queiroz (ESALQ). Universidade de São Paulo (USP). Piracicaba , SP, Brazil

Abstract

In tropical soils the adsorption of phosphorus is higher onto the oxide surface, reducing the availability to plants. Thus, exploration of the soil by the roots becomes important in rhizospheric region, where the interaction between roots, plants, and, soil microorganisms is intense. The aim of this project is to evaluate the dynamic of phosphorus in the sugarcane rhizosphere under the application of doses and sources of phosphorus in the presence and absence of filter cake. Three experiments will be conducted in greenhouse at Department ESALQ - USP. The soil that will be used is a Latossolo Vermelho-Amarelo from Piracicaba - SP, in randomized blocks with four replications. The first experiment will be conducted in factorial design of 5x2 with four genotypes and absence of plants, submitted the presence and absence of phosphorus. For this experiment will be made morphological and root colonization analysis. The second experiment will be conducted in a factorial design of 2x3 with and without filter cake (10 t DM ha-1) with soluble phosphate, natural phosphate and absence of phosphorus. The rhizosphere will be collected in 5 different distances from the rhizoplane (mm): I) 0-2; II) 2-4; III) 4-6; iv) 6-8; v) 8-10. The third experiment will include the best genotype of the experiment 1 and the best source of phosphorus of the experiment 2, which will be conducted as described in experiment 2, whose treatments will be 5 doses of phosphorus. In this experiment will be analysed the acid phosphatase activity, the P content of the microbial biomass, soil pH and metabolite analysis. For all the three experiments will be analysed fractionation of soil P, dry weight for shoots and roots, and N, P and K in the plant tissue.