agridat (version 1.12)

kang.maize: Maize yields at 4 locs in 3 years in Louisianna.

Description

Maize yields at 4 locs in 3 years in Louisianna.

Usage

data(kang.maize)

Format

gen

genotype factor, 17 levels

env

environment factor, 12 levels

yield

yield, tonnes/ha

environment factor, 13 levels

year

year, 85-87

loc

loc factor, 4 levels

Details

Yield trials were conducted at four locations (Alexandria, Baton Rouge, Bossier City, and St. Joseph) in Louisiana during 1985 to 1987. Each loc was planted as RCB design with 4 reps. Mean yields are given in this data.

Examples

# NOT RUN {
data(kang.maize)
dat <- kang.maize

# Sweep out loc means, then show interaction plot.
require(reshape2)
mat <- acast(dat, gen~env, value.var='yield')
mat <- sweep(mat, 2, colMeans(mat))
dat2 <- melt(mat)
names(dat2) <- c('gen','env','yield')
require(lattice)
xyplot(yield~env|gen, data=dat2, type='l', group=gen,
       panel=function(x,y,...){
         panel.abline(h=0,col="gray70")
         panel.xyplot(x,y,...)
       },
       ylab="Environment-centered yield",
       main="kang.maize - maize hybrid yields", scales=list(x=list(rot=90)))

# Weather covariates for each environment.
covs <- data.frame(env=c("AL85","AL86","AL87", "BR85","BR86","BR87",
                     "BC85","BC86","BC87", "SJ85","SJ86","SJ87"),
                   maxt=c(30.7,30.2,29.7,31.5,29.4,28.5, 31.9, 30.4,31.7, 32,29.6,28.9),
                   mint=c(18.7,19.3,18.5, 19.7,18,17.2, 19.1,20.4,20.3, 20.4,19.1,17.5),
                   rain=c(.2,.34,.22, .28,.36,.61, .2,.43,.2, .36,.41,.22),
                   humid=c(82.8,91.1,85.4, 88.1,90.9,88.6, 95.4,90.4,86.7, 95.6,89.5,85))


# }