Colourful Biometrical Analysis for Plant Breeding and Genetics R package BKBreed version 0.3.2 A compact, colour-first toolkit for the analysis of plant breeding and genetics field experiments. It provides analysis of variance for the randomised block design (RBD) and factorial RBD, a check-anchored intra-block analysis for augmented alpha-lattice designs, and the core biometrical-genetics workflow used in crop improvement: estimation of genetic variability (genotypic and phenotypic coefficients of variation, broad-sense heritability, expected genetic advance), genotypic and phenotypic correlation, path-coefficient analysis, line x tester and Griffing diallel combining-ability analysis (general combining ability and specific combining ability), Mahalanobis D-square genetic-divergence analysis with Tocher and hierarchical clustering, and genotype-by-environment stability analysis (Eberhart-Russell regression and the additive main effects and multiplicative interaction (AMMI) model). Methods follow Griffing (1956) <doi:10.1071/BI9560463> and Eberhart and Russell (1966) <doi:10.2135/cropsci1966.0011183X000600010011x>. Every analysis returns a tidy result object and a publication-ready 'ggplot2' figure using a bespoke high-contrast colour system. Software Depends: R (>= 4.0.0) Imports: stats, utils, grDevices, ggplot2 Suggests: ggrepel, patchwork, knitr, rmarkdown, testthat (>= 3.0.0) Praveen Kumar B. K. <bkpraveenars@gmail.com> Comprehensive R Archive Network (CRAN) Praveen Kumar B. K. [aut, cre] GPL-3 2026-07-30 application/tgz https://CRAN.R-project.org/package=BKBreed doi:10.32614/CRAN.package.BKBreed