QUALITY CHARACTERISTICS OF THE LANGDON DURUM-DICOCCOIDES CHROMOSOME SUBSTITUTION LINES

The introduction of genes from wild relatives of wheat Triticum aestivum L. em. Thell., can improve certain quality characteristics such as grain protein content, but these alien genes may affect some of the desirable quality traits. The objective of this study was to determine the chromosomal location of genes affecting quality traits of the 'Langdon' durum T. turgidum L.-T. turgidum var. dicoccoides chromosome substitution lines. Each chromosome of var. dicoccoides was represented by five substitution lines and 13 of the 14 chromosomes were included, for a total of 65 lines. The substitution lines, the recurrent parent Langdon, and three check cultivars were grown in replicated field experiments at two locations in 1989. The quality evaluation included kernel, milling, semolina, and spaghetti characteristics. Differences between lines were significant for all traits studied. Dicoccoides chromosomes 3A and 3B produced semolina high in specks. The substitution lines and Langdon were deficient for yellow pigments in the semolina and in the spaghetti. Several substitution lines had significantly more pigment than Langdon, but none were equal to the other check cultivars. The dicoccoides 6B chromosome substitution lines were superior to Langdon for semolina protein content, mixogram score, spaghetti firmness, cooked weight, and cooking residue. The 1B substitution lines were equal to Langdon in protein, but were superior for traits associated with strong gluten.