Triticeae Genomics and Genetics, 2024, Vol.15, No.5, 277-286 http://cropscipublisher.com/index.php/tgg 278 The study provides an overview of recent advances in the genetic improvement of Triticale and black wheat, particularly in stress-prone environments. This study will assess the impact of global climate change on crop productivity and highlight the role of stress-resistant breeding in mitigating these effects. It will also explore the genetic contributions of rye to Triticale, emphasizing its importance in breeding for abiotic and biotic stress tolerance. It will discuss current breeding challenges and opportunities, particularly in integrating modern genomic tools to address these stress factors. Finally, it will evaluate the progress and future directions in breeding Triticale and black wheat for enhanced resilience to environmental pressures. 2 Genetic Insights into Triticale’s Stress Tolerance 2.1 Genomic composition of Triticale and its influence on stress adaptation Triticale is a hybrid cereal, derived from the cross between wheat (Triticum spp.) and rye (Secale cereale), combining the genetic traits of both species. The genomic structure of Triticale plays a pivotal role in its adaptation to stress environments. The wheat genome contributes to high grain yield and superior quality, while the rye genome offers tolerance to various abiotic stresses such as drought, salinity, and freezing temperatures. This combination allows Triticale to outperform both wheat and rye in stress-prone environments, particularly in areas with poor soil fertility and water availability. The wheat-rye hybrid nature of Triticale, especially the presence of rye chromosomes like 4R and 5R, has been shown to enhance its resistance to environmental stress factors, such as low temperatures and salinity (Golebiowska-Paluch and Dyda, 2023). 2.2 Key quantitative trait loci (QTLs) associated with drought, salinity, and temperature stress tolerance Several quantitative trait loci (QTLs) have been identified that are critical for Triticale’s stress resilience, particularly for tolerance to drought, salinity, and temperature extremes. Notably, QTLs located on rye chromosomes 4R, 5R, and 6R are associated with both abiotic and biotic stress tolerance. These loci influence traits such as drought resistance and freezing tolerance by controlling physiological processes like water retention, cell membrane stability, and osmotic balance. The QTLs on 5R and 6R are of particular importance for drought tolerance, as they regulate water use efficiency and enhance photosynthetic stability under water deficit conditions. Furthermore, QTLs for salinity tolerance have also been mapped to chromosomes 5R and 7R, indicating their role in ion regulation and osmotic adjustment under salt stress (Hura et al., 2017). Additionally, research has shown that specific QTLs located on the wheat-derived chromosome 7A are crucial for freezing tolerance, controlling the recovery and survival rates of plants exposed to freezing temperatures. 2.3 Genetic markers linked to disease resistance inTriticale In terms of disease resistance, several genetic markers have been linked to QTLs associated with resistance to common diseases such as powdery mildew and snow mold. For example, QTLs on rye chromosome 5R are associated with enhanced resistance to biotic stresses, including fungal pathogens. These QTLs influence plant height and spike traits, which are indirectly related to resistance mechanisms by improving airflow and reducing humidity around the plant surface, thus limiting pathogen infection (Golebiowska-Paluch and Dyda, 2023). Furthermore, molecular markers have been identified that are linked to genes conferring resistance to powdery mildew and snow mold, particularly on the rye chromosomes 4R and 5R, providing opportunities for marker-assisted selection (MAS) in breeding programs aimed at improving disease resistance. 3 Progress in Molecular Breeding to Improve Stress Resistance of Triticale 3.1 Marker-assisted selection (MAS) for improving stress resilience inTriticale Marker-assisted selection (MAS) is a powerful tool used in modern breeding programs to improve stress resistance by utilizing molecular markers associated with desirable traits. In Triticale, MAS has proven effective in transferring multiple stress resistance genes, particularly for abiotic stresses like drought and salinity. By selecting specific markers linked to stress tolerance genes, breeders can accelerate the incorporation of these traits into elite lines without the long timelines typically associated with traditional breeding methods. MAS also enables the combination of multiple stress-resistant traits in a single variety through gene pyramiding, a process used in crops like rice and maize, which can also be applied to Triticale (Das and Rao, 2015). Recent studies demonstrate that MAS has the potential to improve complex traits, such as drought and disease tolerance, in
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