Bruna Elaine de Almeida Silva
AUTHOR: Bruna Elaine de Almeida Silva
TITLE: BEHAVIOR OF CORN LINES TO RESISTANCE TO THE FALL ARMYWORM
ADVISOR: : Prof. Dr. Edésio Fialho dos Reis, Co-advisor: Prof. Dr. Fernando Simões Gielfi
APPROVAL DATE: 03/22/2019
Abstract:
The fall armyworm stands out as a key pest for the maize crop, so genetic breeding programs exploring the selection of populations with a certain level of resistance appear as an alternative for the development of resistant cultivars. In this context, the objective of this work was to evaluate endogamic maize strains in relation to resistance to attack of the fall armyworm, in order to obtain improved cultivars. The experiment was conducted in the second crop 2017/18, using 169 maize lines originating from populations from commercial hybrids, creole populations and semiexotic populations. The experimental design was in incomplete blocks, in a 13x13 lattice scheme, with 2 replicates, where the experimental unit was represented by the 169 lines, which were evaluated in the field, through a scale of notes of visual damages. Subsequently, leaves of these lines were collected, forty days after sowing, to perform resistance tests of the non-preference type for feeding. The most and least preferred lineages for the caterpillars in the non-preference test for feeding were selected to be used in the antibiosis test, where the feeding of the caterpillars was obtained by collecting leaves of maize lines grown in a greenhouse. The results were submitted to analysis of variance and the means analyzed by the Scott-Knott test, at 5% probability. It was not possible to verify any type of resistance in the maize lineages evaluated in the field, nevertheless genetic variability was found in the lines analyzed in the laboratory, where the 94 of origin 2B587 and 137 originated from RVCERC presented resistance mechanisms of the non-preference type for feeding and antibiosis, promising to increase the efficiency of resistant cultivars in breeding programs.
