Épocas de corte e a produtividade em genótipos de cana-de-açúcar, em cana-soca

Abstract

The sugarcane shows different performances when submitted to different production environments and harvest dates. This work will assist in choosing the better harvest date for each genotype, in a way to show its greater agro-industrial potential. The aim of this work was to evaluate sugarcane genotypes' agro-industrial productivity in different harvest dates, in frst ratoon, in the year of 2007. The experiment was installed on march 15 th, 2005, at the Usina Alto Alegre, in Colorado, northwest of Paraná State. The experiment's place has ground classified as latossolo vermelho-amarelo, and climate classified as Cfa, according to Köppen classification. The statistical design used was completely randomized design in factorial arrangement of 3×10, being three harvest dates (April 15 th, July 15th and October 15th) and ten genotypes. It was evaluated Pol % cana (sugar polarization), TCH (ton ha -1 of cane) and TPH (ton ha-1 of Pol). The experimental plot was composed by four rows, with 1,10 meters between each row and 8,0 meters of length, and 18 buds per linear meter. In the conditions of the present work, there was significant interaction between harvest dates and genotypes, considering that the genotypes suffered influence from the harvest dates in its agro-industrial productivity. The decision of the harvest date of each sugarcane genotype must not be based only on the technological standards, therefore, a high value of Pol can cannot mean high agro-industrial productivity.