Incidence of rust in coffee cultivaras under the climatic conditiond of Presidente Prudente, SP

Abstract

Rust is the most common disease in coffee crops. The development of new varieties through genetic crossing isconsidered the best way to control the fungus Hemileia vastratix Berk & Br. The study aimed to evaluate the incidence of rust in fivevarieties of coffee grafted on Apoatã (IAC 2258) (Coffea canephora): Icatu vermelho (IAC 4045), Icatu amarelo (IAC 2944), Catuaívermelho (IAC 99), Mundo Novo (IAC 388-17-1) and Obatã (IAC 1669-20) and cultivate Icatu vermelho (IAC 4045) without grafting,totaling six treatments. The test was conducted in Presidente Prudente, SP, in random blocks with ten plants per plot, spaced at 3.5 x1.0 m. During May 2007 to February 2008 we collected two sheets every 15 days at random in a third of the coffee trees, to evaluatethe presence or absence of infectious pustules from yellow to orange on the abaxial surface of leaves. The area under the rust progresscurve was calculated for each cultivar. The infestation data were subjected to analysis of variance and correlated with climatic data.It was concluded that infection differed among cultivars and was lower in cultivars Obatã IAC 1669-20 and Icatu amarelo IAC 2944.Disease incidence was negatively correlated with the absolute minimum and maximum average monthly temperatures, but not with themonthly rainfall.