agridat (version 1.23)

denis.ryegrass: Multi-environment trial of perennial ryegrass in France

Description

Plant strength of perennial ryegrass in France for 21 genotypes at 7 locations.

Format

A data frame with 147 observations on the following 3 variables.

gen

genotype, 21 levels

loc

location, 7 levels

strength

average plant strength * 100

Details

INRA conducted a breeding trial in western France with 21 genotypes at 7 locations. The observed data is 'strength' averaged over 7-10 plants per plot and three plots per location (after adjusting for blocking effects). Each plant was scored on a scale 0-9.

The original data had a value of 86.0 for genotype G1 at location L4--this was replaced by an additive estimated value of 361.2 as in Gower and Hand (1996).

References

Gower, J.C. and Hand, D.J., 1996. Biplots. Chapman and Hall.

Examples

library(agridat)
data(denis.ryegrass)
dat <- denis.ryegrass

# biplots (without ellipses) similar to Denis figure 1
libs(gge)
m1 <- gge(dat, strength ~ gen*loc, scale=FALSE)
biplot(m1, main="denis.ryegrass biplot")