Participation of Wheat and Rye Genome in Drought Induced Senescence in Winter Triticale (X <em>Triticosecale</em> Wittm.)

Abstract

The aim of the study was to identify the regions of triticale genome responsible for senescence under drought induced during the generative stage. We performed quantitative analysis of chlorophylls (a and b), carotenoids, soluble carbohydrates, and phenolic compounds. QTL (Quantitative Trait Loci) calculations were based on a previously developed and characterized genetic map involving 92 lines of doubled haploid derived from F1 hybrid ‘Hewo’ × ‘Magnat’ and two DH parental lines (‘Hewo’ and ‘Magnat’). We identified seven QTLs, including four on chromosome 2A, one on chromosome 1R, and two on chromosome 6R. Only three loci, QSPh.2A.1, QSC.2A.2 and QSC.2A.4 mapped single traits, i.e., the content of soluble phenolics and carbohydrates. Single QTL (QCSPh.1R) was responsible for changes in the levels of chlorophyll a and b, carotenoids and soluble phenolics. The remaining three loci, QCSPhC.2A.3, QCSPhC.6R.1 and QCSPhC.6R.2 controlled changes in the entire set of investigated traits. We also identified candidate genes for the investigated traits. The loci on chromosome 2A encoded proteins responsible for oligosaccharide transportation and mechanical properties of xylem and the genes regulating carbohydrate metabolism. The chromosomes 1R and 6R contained functional genes possibly associated with carbohydrate and phenolic metabolism.

Keywords

• X <i>Triticosecale</i>
• drought stress
• senescence
• QTLs
• carbohydrates
• chlorophyll
• phenolics