agridat (version 1.8.1)

crossa.wheat: Wheat yields for 18 genotypes at 25 locations

Description

Wheat yields for 18 genotypes at 25 locations

source

Crossa, J and Fox, PN and Pfeiffer, WH and Rajaram, S and Gauch Jr, HG. (1991). AMMI adjustment for statistical analysis of an international wheat yield trial. Theoretical and Applied Genetics, 81, 27--37. Used with permission of Jose' Crossa.

Details

Grain yield from the 8th Elite Selection Wheat Yield Trial to evaluate 18 bread wheat genotypes at 25 locations in 15 countries. Locations lllrr{ Code Country Location Latitude (N) Elevation (m) AK Algeria El Khroub 36 640 AL Algeria Setif 36 1,023 BJ Bangladesh Joydebpur 24 8 CA Cyprus Athalassa 35 142 EG Egypt E1 Gemmeiza 31 8 ES Egypt Sakha 31 6 EB Egypt Beni-Suef 29 28 IL India Ludhiana 31 247 ID India Delhi 29 228 JM Jordan Madaba 36 785 KN Kenya Njoro 0 2,165 MG Mexico Guanajuato 21 1,765 MS Mexico Sonora 27 38 MM Mexico Michoacfin 20 1,517 NB Nepal Bhairahwa 27 105 PI Pakistan Islamabad 34 683 PA Pakistan Ayub 32 213 SR Saudi Arabia Riyadh 24 600 SG Sudan Gezira 14 411 SE Spain Encinar 38 20 SJ Spain Jerez 37 180 SC Spain Cordoba 38 110 SS Spain Sevilla 38 20 TB Tunisia Beja 37 150 TC Thailand Chiang Mai 18 820 }

References

Jean-Louis Laffont, Kevin Wright and Mohamed Hanafi (2013). Genotype + Genotype x Block of Environments (GGB) Biplots. Crop Science. In press.

Examples

## This does not work with agricolae 1.1-9
dat <- crossa.wheat

# AMMI biplot.  Fig 3 of Crossa at al
library(agricolae)
m1 <- with(dat, AMMI(E=loc, G=gen, R=1, Y=yield))
b1 <- m1$biplot[,1:4]
b1$PC1 <- -1 * b1$PC1 # Flip vertical
plot(b1$yield, b1$PC1, cex=0.0,
     text(b1$yield, b1$PC1, cex=.5, labels=row.names(b1),col="brown"),
     main="AMMI BIPLOT", xlab="Average yield", ylab="PC1", frame=TRUE)
mn <- mean(b1$yield)
abline(h=0, v=mn, col='wheat')

g1 <- subset(b1,type=="GEN")
text(g1$yield, g1$PC1, rownames(g1), col="darkgreen", cex=.5)

e1 <- subset(b1,type=="ENV")
arrows(mn, 0,
       0.95*(e1$yield - mn) + mn, 0.95*e1$PC1,
       col= "brown", lwd=1.8,length=0.1)