Advanced high yielding lines of hulless winter barley for the development of functional foods

Barley is interesting from a nutritional point of view for the typical grain composition that makes it an ideal cereal for the production of "functional foods". Such components are mainly beta-glucans (soluble fiber) and tocols (vitamin E). The beta-glucans are an heterogeneous family of polysaccharides, typical of barley and oats, that constitute the cellular walls of the seed endosperm, and that, introduced into diet, can contribute to the lowering of hematic cholesterol and of hematic glucose content. Therefore, the interest of researchers is for the production of baked foods containing barley flour, then rich in dietary fiber, i.e. beta-glucans. Also by using specific techniques for the enrichment of flour in beta-glucans (e.g. turboseparation), it has been possible to produce high beta-glucan bread and bakery products made of mixed wheat and enriched barley flour with organolectic characteristics not too far from those made of pure wheat flour. Hulless barley, lacking of glumelets, gives a grain of superior quality for food respect to hulled barley, although it yields generally less, for both the absence of the glumelets and the lower efforts on the improvement of the hulless germplasm. In the Istituto Sperimentale per la Cerealicoltura it had been active a breeding program for winter hulless barley, with the main objective of yield stability, and based on pedigree and backcross schemes that lead to the release of cultivar 'Zacinto' (2000). Inside the frame of the programme, a SCAR marker has been developed for the recognition of heterozyigous genotypes in hulled x hulless backcrosses, and this marker has been used for the acceleration of such breeding schemes. In a second phase, the resistance to the soil-borne mosaic virus complex (BaMMV-BaYMV), and to the yellow dwarf virus (BYDV) have been introduced in the programme, by means of molecular Marker-Assisted Selection. A specific replicated yield trial has been recently set up in which the advanced high yielding hulless lines, together with hulled and hulless checks have been evaluated in different locations in Italy for the average production of beta-glucans and tocols, and for the evaluation of the effects of the genotype x environment interaction on the production of such compounds. In the last years, the virus-resistant advanced lines have been also crossed to Canadian and Australian hulless waxy lines with the aim to develop high yielding, virus-resistant and high beta-glucan winter barleys. In fact it is well-known that waxy barley genotypes contain consistently higher-beta-glucans respect to the ones with normal starch. The most recent results of the hulless barley breeding programme for the production of functional foods at the Istituto Sperimentale per la Cerealicoltura are here presented.