Genetic parameters and resistance of cacao progenies to Ceratocystis wilt under natural infection. In: Agrotrópica v. 27 p. 215-218, 2015.

Abstract

The objective of this study was to evaluate the resistance to the fungus Ceratocystis cacaofunesta, causing Ceratocystis wilt, a lethal disease of cacao. In March 2005, in the Joaquim Bahiana Experimental Station (ESJOB) of the Cocoa Research Center (Cepec) located in the municipality of Itajuípe, Bahia, Brazil was an experiment installed in the field with progenies of 27 crosses arranged in randomized blocks with spacing of 3x3 meters with plots of 30 plants and four repetitions, with a total of 120 plants /crosses. The plants of progenies from 27 crosses were evaluated in relation to disease, and, in October 2012, data of the incidence of dead plants were subjected to analysis of variance and heritability. The mean disease incidence ranged from 0.83 to 51.66%, while the overall mean was 16.19% of dead plants. Progenies showed significant differences in incidence and resistance to Ceratocystis wilt. Natural selection performed in this experiment for resistance to Ceratocystis cacaofunesta was efficient considering the high heritability (h2 = 0.92) and the value of the relationship CVg / CVe = 1.71.