SStatistical Analyses of the Outputs of 24 Varieties of Hard Wheat Experimented on Several Sites and During Two Successive Years in Algeria

A project of improvement and backing of adaptation of the national varietal system of the hard wheat in Algeria, duct jointly by the Instituto Agronomico per the Otremare (IAO) of Italy and l Institut Technique des Grandes Cultures (I.T.G.C) of Algeria, the area of survey covers the whole north Algeria with total surface of about 250291 km2, where 24 local and introduced varieties of hard wheat have been tested through 17 sites of experimentations in order to study the influence of the pedoclimatic variability on the productivity of every variety. The statistical analysis of the middle outputs gotten of the 24 varieties of hard wheat on 2 consecutive years showed that some very highly significant differences exist, on the one hand, between years for practically the two third of the sites and, on the other hand, between sites for each of the two years and this for the set of the 24 varieties. Whereas only some significant differences exist between the 24 varieties for each of the two years and for every site of survey.