Genotype × Environment Interactions in Maize Hybrids from Temperate or Highland Tropical Origin

Abstract

Exotic germplasm is often used in maize (Zea mays L.) breeding programs. However, the occurrence of genotype × environment interactions (GEIs) may mask the potential utility of exotic material. Our objective was to understand better GEIs for temperate, temperate × highland, and highland tropical maize genotypes cultivated under temperate or highland tropical conditions. We related yield instability to GEIs observed for vegetative or flowering traits, and determined the response of these vegetative or flowering traits to temperature and photoperiod. Forty‐one hybrids grown in four environments were observed for several pre‐flowering, flowering, and yield traits. Grain yield variation was related to two major adaptation factors: disease resistance and planting‐to‐silking duration (PSD). Yield variations were also related to variation in traits measured before flowering, such as emergence duration or early growth. For emergence duration, leaf stage at a given date, or leaf size, one simple temperature covariate accounted for more than half of the interaction sum of squares. Temperate × highland tropical hybrids had an intermediate behavior and were more stable than the pure temperate or pure highland tropical hybrids. For total number of leaves, photoperiod at tassel initiation explained a higher proportion of the interaction sum of squares than temperature. The response of highland tropical hybrids to photoperiod was larger than for the temperate hybrids. We recommend breeders who wish to introduce exotic material into adapted material utilize mass selection and/or advanced backcrossing, with marker assisted selection for specific traits with low heritability, such as cold tolerance.

Testcross performance and diversity analysis of white maize lines derived from backcrosses containing exotic germplasm

“…The absence of signiWcant year £ testcross, location £ testcross, and year £ location £ testcross interactions for most traits recorded in this trial indicates that the testcrosses had consistent performance in diverse production environments. Similarly, GrauVret et al (2000) reported consistent performance of temperate £ tropical highland hybrids across diverse growing environments, mainly due to their resistance to diseases, temperature and photoperiod insensitivity, which were the major adaptation factors. Since the testcrosses contained only 12.5% exotic germplasm with the rest of its genome coming from the tester (50%) and the recurrent parent (37.5%), this may contribute to reduced testcross £ environment interaction.…”

Evaluation of genotype x environment interactions in maize hybrids using GGE biplot analysis

“…They concluded that none of them significantly affected genotype x environment interaction for corn yield. Giauffret et al (2000) showed yield instability to the genotype x environment interactions observed for vegetative or flowering traits, and determined the response of these vegetative or flowering traits to temperature and photoperiod in maize hybrids. Besides, Oliveira et al (2003) stated that most maize hybrids demostrated low contribution to genotype x environment interaction, although the single crosses presented greater mean yield, and the double hybrids showed greater yield stability for ten environments in Central Brazil.…”

Effect of recombination in the maize breeding population with exotic germplasm on the yield stability

“…GEI represents an obstacle in the identification of the superior and stable genotypes and as a component of the trait phenotypic variability, decreases heritability, hinders complex trait breeding and also conceals potential usefulness of exotic germplasm (Giauffret et al 2000). It is to be expected that the genetic structure of a population will influence the size of GE interactions (Becker and Léon 1988).…”