Analysis of genotype-by-environment interaction for disease severity index of MRCV in maize inbred lines by using the AMMI model

ROSSI, EZEQUIEL A.; RUIZ, MARCOS; BIANCONI, GABRIEL; BALZARINI, MÓNICA; BONAMICO NATALIA C.

Merlo, San Luis

Jornada; XXXV REUNIÓN ANNUAL de la Sociedad de Biología de Cuyo; 2017

Sociedad de Biología de Cuyo

Plant germplasm collections are a valuable resource in genetic plant improvement. The germplasm that will be utilized for association mapping should have the greatest possible phenotypic variation. The objective of this work was determining the genotype-by-environment interaction (GEI) in maize inbred lines evaluated for disease severity index to Mal de Río Cuarto Virus (MRCV). A diverse population of 291 maize inbred lines developed and provided by the International Maize and Wheat Improvement Center (CIMMYT) were evaluated. Multienvironment trials included two years and three locations in province of Córdoba where the MRCV is endemic. Environment combinations were Chaján 15/16 (E1), Chaján 15/16 (E2), Chaján 16/17 (E3), Río Cuarto 15/16 (E4), Río Cuarto 16/17 (E5), Rodeo Viejo 16/17 (E6) and Rodeo Viejo 16/17 (E7). In Chaján 15/16 and Rodeo Viejo 16/17 the sowing dates were two. For each maize inbred line, disease severity index (DSI) was evaluated by a partially replicated experiment (p-rep) with a 12% of test lines in three replications. Data was analyzed using the Additive Main effect and Multiplicative Interaction (AMMI) model to establish the genotype-by-environment interaction. Given that in some environments the disease presence was very low, the AMMI analysis was performed only with the environments E1, E3, E6 and E7, where the disease presence allowed differentiate the genotypes. The AMMI model allowed us to identify genotypes with high DSI values in each environment, as well as, genotypes that showed stability through environments.