Effects of breeding activity on durum wheat traits breed in Italy during the 20th century

Abstract

Italy is the first world producer of pasta from durum wheat (Triticum durum Desf.) and an intense breeding activity has been conducted over the last century to support the long tradition of pasta making. This manuscript reviews the results achieved through the Italian breeding programs over last century. The analysis of data allows to appreciate the selective pressure imposed by the breeders on plant height and phenology to select cultivars well adapted to the Italian semi-arid conditions, where early maturity allows to escape the drought season. The annual genetic gain in terms of yield ranged from 17 to 24.6 kg ha-1 year-1 and it was most clearly associated with a higher kernels number m-2 indicating a larger grain-sink size and a higher number of spikes m-2. Regarding the quality traits, the grain protein concentration showed a decreasing trend over time of release of about 0.02% per year, confirming the negative relationship with grain yield.The progressive incorporation into recent cultivars of favourable alleles (7+8 glutenin subunit composition) coding for superior quality subunits reflects the improvement in pasta making quality of the recent genotypes.