Agronomic characterization and responses to coffeeleaf rust in coffee progenies resistant to the gall nematode meloidogyne exigua

Abstract

The aim of this study was to determine agronomic characteristics and responses to the coffee leaf rust fungus (Hemileia vastatrix Berk. et Br.) in coffee progenies resistant to the gall nematode Meloidogyne exigua. The experiment was conducted in December 2000 at Ouro Verde Farm (FazendaOuro Verde), located in the municipality of Campos Altos – Minas Gerais (MG). Ten F3:4 progenies were evaluated. They were derived from crosses between CIFC 2570 Timor Hybrid selections and Catuaí cultivars known to be resistant to M. exigua. The Catuaí Vermelho IAC 99 cultivar served as a control. A randomized block design with three replicates was used. In total, there were thirty-three plots consisting of eight plants each. The following characteristics were assessed between the harvests of 2011/2012 and 2014/2015: (a) yield expressed as processed coffee bags ha-1; (b) rust incidence and severity; (c) vegetative vigor; (d) percentage of coffee fruits at the “cherry” stage; (e) percentage of floaters; (f) crown diameter; (g) percentage of coffee beans of size sieve 17 and higher; and (h) sensory analysis of the coffee beverage. The results indicated the following: (a) the H514-7-14-2, H514-7-4-5, H493- 1-2-2, H514-7-16-3, H514-7-8-11, H518-2-10-1, and H514-5-2-4 progenies were the most productive; (b) all progenies showed promising resistance to coffee leaf rust; (c) all genotypes had the potential for specialty coffee production; (d) the H493-1-2-2 progeny showed resistance both to rust and the nematode, and has good potential for specialty coffee production; and (e) the yields of the H514-7-8-11, H518-2-10-1, H514-5-2-4, H514-7-16-3, H514-7-14-2, H514-7-4-5, and H493-1-2-2 progenies were significantly higher than that of the Catuaí IAC 99 control