The Wheat (Triticum aestivum) – Intermediate Wheatgrass (Thinopyrum intermedium) – Couch Grass (Elymus repens) species complex is a potential case of gene flow between crop and wild relatives in the Central European area. Understanding the genomic constitutions and evolutionary histories of both polyploid Wheatgrasses and the assessment of frequency of their hybrid formation are basic prerequisities for understanding the gene flow within the whole species complex. and Václav Mahelka.
We examined the physiological and biochemical responses of two halophytic grasses with different photosynthetic pathways, Puccinellia tenuiflora (C3) and Chloris virgata (C4), to saline-alkaline stresses. Plants were grown at different Na2CO3 concentrations (from 0 to 200 mM). Low Na2CO3 (< 12.5 mM) enhanced seed germination and plant growth, whereas high Na2CO3 concentrations (> 100 mM) reduced seed germination by 45% in P. tenuiflora and by 30% in C. virgata. Compared to C. virgata, P. tenuiflora showed lower net photosynthesis, stomatal conductance, intercellular CO2 concentration, and water-use efficiency under the same treatment. C. virgata exhibited also relatively higher ATP content, K+ concentration, and the K+/Na+ ratio under the stress treatments implying that salt tolerance may be the main mechanism for salt resistance in this species. Our results demonstrated that the C. virgata was relatively more resistant to saline-alkaline stress than the co-occurring P. tenuiflora; both two species adapt to their native saline-alkaline habitat by different physiological mechanisms., C. Y. Guo, X. Z. Wang, L. Chen, L. N. Ma, R. Z. Wang., and Obsahuje bibliografii
Anthoxanthum odoratum (Sweet Vernal Grass), is a widespread grass species native to Eurasia and common also in the Czech Republic. Its name is derived from distinct scent, particularly strong in dry state, caused by coumarins. Eight other Anthoxanthum species can be found in Europe, one of which (A. alpinum) occurs in the Czech Republic. It replaces A. odoratum at higher altitudes. The genus encompasses both di - ploids and polyploids that have complex evolutionary history. We used DNA flow cytometry together with molecular markers to gain detailed insights into evolutionary processes shaping the genus. and Zuzana Khodlová, Pavel Trávníček.