Die Bodenkultur - Journal for Land Management, Food and Environment
A. Blanco, A. Gadaleta and R. Simeone:
Variation for yield and quality components in durum wheat backcross inbred lines derived from ssp. dicoccoides
The use of wild germplasm as a source of quantitative trait allelic variation is important for crop improvement and breeders.
The wild tetraploid wheat Triticum turgidum (L.) Thell. ssp. dicoccoides (Korn.) shows particular promise as a donor of useful genetic variation for several traits, including disease resistance, drought tolerance, yield components, protein quantity and quality. The effectiveness of the inbred backcross method for introgressing quantitative traits from the ssp. dicoccoides (donor parent) into the cultivated durum wheat cv. ‘Latino’(recurrent parent) was examined. An inbred backcross population at BC3 level was developed and tested over two years (2001 and 2002) at two locations (Valenzano and Gaudiano) for grain protein content, grain yield, test weight, 1000-grain weight, plant height and heading time. Variation among backcross inbred lines (BILs) was observed for all traits. Significant line x environment interactions suggest that genotype x environment effects may be important for every traits. Large phenotypic correlations between grain yield and related traits and between grain yield and protein content were estimated. Six superior BILs were selected for increased protein content and one BIL for increased grain yield, while retaining the desirable agronomic characteristics of the recurrent parent and without other undesirable characteristics of the donor parent. The backcross lines and the information gathered during this study will be useful for mapping novel alleles for agriculturally important quantitative traits and will be exploited to formulate strategies for producing elite durum lines by marker-assisted selection.
Key words: durum wheat, ssp. dicoccoides, backcross inbred lines, grain yield, protein content.