Genetic Gain in the Resistance of Arabica Coffee Progenies to Root‐Knot Nematode

• DOI: 10.2135/cropsci2016.07.0606
• Publication Date: 2017-04-20T19:07:14Z
• Authors: R. Machado Rezende; V. Teixeira Andrade; S. Maria Lima Sal...; J. Costa de Rezende; J. de Oliveira Me...; Gladyston R. Carv...
• Keywords: Root-knot nematode; Eggs per gram

The nematode Meloidogyne exigua infests Arabica coffee ( Coffea arabica L.) plants, leading to severe growth reduction in young trees and decreased bean yield. We investigated the responses of plants this estimated genetic gain progenies derived from cross between cultivar Catuaí Timor hybrid. evaluated 85 F 4:5 progenies; cultivars Mundo Novo IAC 379‐19 Vermelho 99 were used as susceptible controls, Paraíso MG H 419‐1 IPR 100 resistant controls. Progeny using gall index (GI), reproduction factor (RF), (RFR), number eggs juveniles (J2) per gram roots (NEJGR). 75 M. . Little or no segregation for resistance was observed within progenies, indicating potential homozygosity at locus. GI, RF, RFR, NEJGR showed high genotypic correlation. correlated response when selected indirectly by GI higher than that direct selection. scale allowed decrease population increase resistance; therefore, it can be a selection criterion. Linear regression mean reduced value 450 cycle, which led change phenotypic explained 95% variation. Thus, successive cycles could prevent development tree roots.