Multi-environment trial of winter wheat, 7 years

Multi-environment trial of winter wheat, 7 years, 8 gen

Usage

data("onofri.winterwheat")

Format

A data frame with 168 observations on the following 5 variables.

year

year, numeric

block

block, 3 levels

plot

plot, numeric

gen

genotype, 7 levels

yield

yield for each plot

Details

Yield of 8 durum winter wheat varieties across 7 years with 3 reps.

Downloaded electronic version from here Nov 2015: https://www.casaonofri.it/Biometry/index.html

Used with permission of Andrea Onofri.

Source

Andrea Onofri, Egidio Ciriciofolo (2007). Using R to Perform the AMMI Analysis on Agriculture Variety Trials. R News, Vol. 7, No. 1, pp. 14-19.

References

F. Mendiburu. AMMI. https://tarwi.lamolina.edu.pe/~fmendiburu/AMMI.htm

A. Onofri. https://accounts.unipg.it/~onofri/RTutorial/CaseStudies/WinterWheat.htm

Examples

library(agridat)
data(onofri.winterwheat)
dat <- onofri.winterwheat
dat <- transform(dat, year=factor(dat$year))

m1 <- aov(yield ~ year + block:year + gen + gen:year, dat)
anova(m1) # Matches Onofri figure 1
#> Analysis of Variance Table
#> 
#> Response: yield
#>            Df  Sum Sq Mean Sq  F value    Pr(>F)    
#> year        6 159.279 26.5466 178.3996 < 2.2e-16 ***
#> gen         7  11.544  1.6491  11.0824 2.978e-10 ***
#> year:block 14   3.922  0.2801   1.8826   0.03738 *  
#> year:gen   42  27.713  0.6598   4.4342 6.779e-10 ***
#> Residuals  98  14.583  0.1488                       
#> ---
#> Signif. codes:  0 ‘***’ 0.001 ‘**’ 0.01 ‘*’ 0.05 ‘.’ 0.1 ‘ ’ 1

libs(agricolae)
m2 <- AMMI(dat$year, dat$gen, dat$block, dat$yield)
plot(m2)
title("onofri.winterwheat - AMMI biplot")