Biplot approach with self-incompatibility analyses of sib diallel cross data for Lysimachia monelli (Primulaceae)

Abstract

The biplot is a diagnostic tool used to make a visual appraisal of large data matrices with double entries. It has been most commonly used in crop breeding to evaluate genotype × environment interactions. We have employed the biplot method to study the self- and cross-compatibility reactions as evinced by diallel crosses for full-sib progeny arrays in Lysimachia (Anagallis) monelli, a species that has been shown to have single locus, multiallelic self-incompatibility, homomorphic gametophytic type (GSI). The resultant plots show two and three major groups (inter-compatible, intra-incompatible). In all diallel biplots, the high proportion of the total variation explained by two principal components (PC1 and PC2) indicates one-locus SI. Two to four compatible/incompatible clusters found in the analyzed diallels is in accord with a GSI type. More interestingly, the biplots also showed varying degrees of interaction between plants as females (pollen receiving) and plants as males (pollen donors) in the data from two diallels. The biplot method offers an alternative approach to study the genetic control of self-incompatibility via diallel crosses, and we propose that it might be particularly useful to study complex self-incompatibility systems in which conventional methods for the analysis of sib diallel results have proven difficult.

Keywords:

• Diallels
• genotype by genotype interaction
• single locus gametophytic self-incompatibility

Acknowledgements

We thank to Heredity for permission to reproduce three figures from Talavera et al. (2001).

Disclosure statement

No potential conflict of interest was reported by the authors.

Funding

MBB thanks to the Consejo de Investigaciones de la Universidad Nacional de Rosario (CIUNR) for financial support.

Author Contributions

MBB contributed with the statistical analysis and interpretation of the results. PEG proposed using the Lysimachia monelli diallel data as a test case for the application of the biplot analysis to self-incompatibility studies. And GRP provided the idea and fundaments for the use and development of biplot analysis on genotype-genotype interaction. All authors contributed equally to the writing of the manuscript.