Agronomic value and plant type of Italian durum wheat cultivars from different eras of breeding

摘要: Durum wheat has been subjected to intense breeding in Italy due its local economic importance. Four groups of Italian cultivars representative different eras were compared northern Syria for yield potential and morphophysiological features at a moderately favourable site, drought tolerance stressful site. Group 1 included indigenous landraces; 2 comprised genotypes selected from exotic landraces (released 1920's–1930's); 3 crosses or mutagenesis involving materials (1950's–1960's); 4 between CIMMYT (from 1970's). Under conditions, increase 1.03 t ha–1 was observed through 4, corresponding genetic gain about 0.017 per year. Such only partly accounted by parallel spike fertility seed weight. Plant stature decreased dramatically 4; remarkable reduction height already attained 3, before the introduction dwarfing genes bread wheat. Earliness heading grain filling duration increased consistently across phases, length crop cycle remaining almost unaltered. No significant improvement resulted activity, suggesting need put more emphasis on selection real stress rather than escape. Overall variation traits, assessed principal components analysis, highlighted great diversity among cultivars, while within Groups lower. Indigenous landraces, little used history, as well novel, unexploited germplasm sources could contribute broaden base region.