Genotypic superiority measure

genotypic_superiority_measure calculate variance of a genotype across environments.

genotypic_superiority_measure(
  data,
  trait,
  genotype,
  environment,
  unit.correct = FALSE
)

Arguments

data

a dataframe containing trait, genotype and environment.

trait

colname of a column containing a numeric vector of interested trait to be analysized.

genotype

colname of a column containing a character or factor vector labeling different genotypic varieties

environment

colname of a column containing a character or factor vector labeling different environments

unit.correct

logical, default is FALSE, returning the stability index with unit equals to squared unit of trait; when TRUE, returning stability index with the unit as same as unit of trait.'

Value

a data table with genotypic superiority measure

Details

Genotypic superiority measure (Lin and Binns, 1988) is calculatd based on means square distance between maximum value of environment j and genotype i. Variety with low genotypic superiority measure is considered as stable. Equation of genotypic superiority measure can be found in vignette file.

References

Lin CS, Binns MR (1988). “A superiority measure of cultivar performance for cultivar \(\times\) location data.” Canadian Journal of Plant Science, 68(1), 193--198. ISSN 0008-4220, https://cdnsciencepub.com/doi/10.4141/cjps88-018.

Author

Tien-Cheng Wang

Examples

data(Data)
res <- genotypic_superiority_measure(
 data = Data,
 trait = "Yield",
 genotype = "Genotype",
 environment = "Environment",
 unit.correct = FALSE)