donnees <- read.table("https://husson.github.io/livre_exo/chap5_ex5.csv", header = TRUE, sep=";", encoding = "latin1")

donnees[,"Insecticide"] <- as.factor(donnees[,"Insecticide"])
library(FactoMineR)
AovSum(Nb.chenilles ~ Insecticide, data = donnees)