Quantitative Trait Loci (QTL) Associated With Leaf Development in Winter Triticale (× Triticosecale Wittmack) Seedlings

The vitality and the development in the seedling stage is crucial in winter cereal’s life cycle, especially before and during winter. It has been reported that rapid seedling establishment and early growth may lead to higher crop yield. Localization of cereal genome regions is not often analysed in the seedling stage. The aim of this study was to identify winter triticale genome regions (QTL) associated with seedling leaves development. Based on ‘Hewo’ x ‘Magnat’ DH lines population genetic map composed of 3539 molecular markers assigned to 20 linkage groups with 4997.4 cM map length, in total 40 loci were identified by a composite interval mapping (CIM). Among them, 22 loci appeared in at least two experiments, were common for all analyzed traits as well as were identified on wheat chromosome 4B and on rye chromosomes 1R, 4R, 5R and 6R. Those loci explained up to 21.7% of phenotypic variation (Qwsl.hm.4R.2) and had LOD value up to 31.1 (Qlsl.hm.5R.1). The results of QTLs of seedling leaves development could be successively associated with QTLs of the freezing and fungal infection seedlings tolerance identified in this mapping population.

Wheat EST sequence assembly facilitates comparison of gene contents among plant species and discovery of novel genes

Using a strategy requiring only modest computational resources, wheat expressed sequence tag (EST) sequences from various sources were assembled into contigs and compared with a nonredundant barley sequence assembly, with ESTs, with complete draft genome sequences of rice and Arabidopsis thaliana, and with ESTs from other plant species. These comparisons indicate that (i) wheat sequences available from public sources represent a substantial proportion of the diversity of wheat coding sequences, (ii) prediction of open reading frames in the whole genome sequence improves when supplemented with EST information from other species, (iii) a substantial number of candidates for novel genes that are unique to wheat or related species can be identified, and (iv) a smaller number of genes can be identified that are common to monocots and dicots but absent from Arabidopsis. The sequences in the last group may have been lost from Arabidopsis after descendance from a common ancestor. Examples of potential novel wheat genes and Triticeae-specific genes are presented.Key words: small grain cereal, genome, wheat, barley, bioinformatics.