| The breeding of Triticum durum by means of interspecies
crosses B. RUSMINI Stazione Fitotecnica, S. Angelo Lodigiano, Milano, Italia In Italy research is now being carried out on a large scale on breeding of Triticum durum, because, also in typical areas, the species is going to be substituted by T. vulgare, which has a markedly superior productivity capacity. As is well-known, Italians are traditionally large consumers of soup-paste, and must, therefore, rely on imports of macaroni wheat for their needs, while in Italy over production of soft grain is deplored. It is particularly interesting, therefore, to review the results, which for the present have been obtained by means of interspecific hybridization at the "Stazione Fitotecnica" of St. Angelo Lodigiano, Milano. From the cross T. turgidum var. psendocervinum x T. durum with the method of a repeated backcrosses using T. durum as the recurrent parent, is obtained a definite increase in number of kernels per spike (above 100 kernels in comparison to 40-60 of the best durum spikes) through an increase in number of florets per spikelet and number of spikelets. Moreover the plant height is lowered as far as 35 cm less than the standard variety of T. durum "Cappelli". The main obstacle encountered in the selection consists of the difficulty in separating those lines which can at least be equal in quality to "Cappelli". From T. dicoccoides crossed to T. durum and backcrosses, are obtained types which present, in comparison with T. durum, a higher winter hardiness, a better tillering, a more intense color of the leaves and larger seeds. From T. durum x T. orientale lines have been obtained which are especially interesting for large dimensions of grains. The cross between T. durum and T. Timopheevi gave types resistant to cold and rust. From T. persicum x T. durum and relative backcrosses, more satisfying results have been obtained. The most evident result is represented by a very much higher increase in floret fertility and a great improvement in the grain which is perfectly hard. It is to be noted that T. durum in all varieties in the growing conditions of North Italy has many soft grains. From T. durum x T. vulgare have been obtained interesting types for winter hardiness, humidity resistance, low stem height and more fertile spike. At the "Stazione Fitotecnica" T. durum has been submitted to a long series of crosses and backcrosses, also with species of Aegilops and Agropyron. These data will be given on another occasion. |