Genotype x environment interaction of crossover type: detecting its presence and estimating the crossover point

Salvatore Ceccarelli, Stefania Grando. (1/10/1999). Genotype x environment interaction of crossover type: detecting its presence and estimating the crossover point. TAG Theoretical and Applied Genetics, 99, pp. 988-995.

Abstract

Genotype-environment interaction (GEI) introduces inconsistency in the relative rating of genotypes across environments and plays a key role in formulating strategies for crop improvement. GEI can be either qualitative (i.e., crossover type) or only quantitative (i.e., noncrossover type). Since the presence of crossover-type interaction has a strong implication for breeding for specific adaptation, it is important to assess the frequency of crossover interactions. This paper presents a test for detecting the presence of crossover-type interaction using the response-environment relationship and enumerates the frequency of crossovers and estimation of the crossover point (CP) on the environment axis, which serves as a cut-off point for the two environments groups where different/specific selections can be made. Sixty-four barley lines with various selection histories were grown in northern Syria and Lebanon giving a total of 21 environments (location-year combinations). Linear regression of the genotypic response on the environmental index represented a satisfactory model? and heterogeneity among regressions was significant. At a 5% level of significance, 38% and 19% of the pairs showed crossover interactions when the error variances were considered heterogeneous and homogeneous, respectively, implying that an appreciable number of crossovers took place in the case of barley Lines responding to their environments. The CP of 1.64 t/ha, obtained as the CP of regression lines between the genotype numbers: 19 and 31, provided maximum genotype x environment-group interaction. Across all environments, genotype nos. 59 and 12 stood first and second for high yield, respectively. The changes in the ranks of genotypes under the groups of environments can be used for selecting specifically adapted genotypes.

Permanent link

https://hdl.handle.net/20.500.11766/13277

DOI

https://dx.doi.org/10.1007/s001220051406

Collections

Agricultural Research Knowledge

Other URI

https://mel.cgiar.org/dspace/limited

AGROVOC Keyword(s)

barley

; Barley

Subject(s)

genotype x environment interaction; crossover point; crossover genotype-environment interaction; linear regression model

Author(s) ORCID(s)

Singh, Murari https://orcid.org/0000-0001-5450-0949