onofri.winterwheat {agridat} | R Documentation

## Yield of winter wheat varieties across 7 years.

### Description

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

### 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.

### 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.

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

Used with permission of Andrea Onofri.

### References

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

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

### Examples

    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

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

[Package agridat version 1.16 Index]