Complete chloroplast genome of Hordeum brevisubulatum: Genome organization, synonymous codon usage, phylogenetic relationships, and comparative structure analysis

Background Hordeum brevisubulatum, known as fine perennial forage, is used for soil salinity improvement in northern China. Chloroplast (cp) genome is an ideal model for assessing its genome evolution and the phylogenetic relationships. We de novo sequenced and analyzed the cp genome of H. brevisubulatum, providing a fundamental reference for further studies in genetics and molecular breeding. Results The cp genome of H. brevisubulatum was 137,155 bp in length with a typical quadripartite structure. A total of 130 functional genes were annotated and the gene of accD was lost in the process of evolution. Among all the annotated genes, 16 different genes harbored introns and the genes of ycf3 and rps12 contained two introns. Parity rule 2 (PR2) plot analysis showed that majority of genes had a bias toward T over A in the coding strand in all five Hordeum species, and a slight G over C in the other four Hordeum species except for H. bogdanil. Additionally, 52 dispersed repeat sequences and 182 simple sequence repeats were identified. Moreover, some unique SSRs of each species could be used as molecular markers for further study. Compared to the other four Hordeum species, H. brevisubulatum was most closely related to H. bogdanii and its cp genome was relatively conserved. Moreover, inverted repeat regions (IRa and IRb) were less divergent than other parts and coding regions were relatively conserved compared to non-coding regions. Main divergence was presented at the SSC/IR border. Conclusions This research comprehensively describes the architecture of the H. brevisubulatum cp genome and improves our understanding of its cp biology and genetic diversity, which will facilitate biological discoveries and cp genome engineering.

Tactics and life strategies of cenopopulation Hordeum brevisubulatum (Trin.) Link

Survival tactics and strategy of Hordeum brevisubulatum the dominant of meadow phytocenoses in CentralYakutia were studied. Traits-indicators annually change ontogenetic tactics, except for the taxonomic trait-indicator.Protective-stress and stress-protective ontogenetic strategy and CS type of ecological-coenotic strategin were established.

Influence of Interactions between Nitrogen, Phosphorus Supply and Epichloёbromicola on Growth of Wild Barley (Hordeum brevisubulatum)

Epichloë endophytes are biotrophic fungi that establish mutualistic symbiotic relationship with grasses and affect performance of the host under different environments. Wild barley (Hordeum brevisubulatum) is an important forage grass and often infected by Epichloë bromicola, thus showing tolerances to stresses. Since the plant growth correlates with both microbial infection and nutrient stoichiometry, this study was performed to investigate whether the function of Epichloë bromicola endophyte to improve host growth depend upon the nitrogen (N), phosphorus (P) fertilization. Epichloë-infected (E+) and Epichloë-free (E−) wild barley plants were subjected to nine types of mixed N (0.2 mM, 3 mM, 15 mM) and P (0.01 mM, 0.1 mM, 1.5 mM) levels treatments for 90 d to collect plant samples and determine multiple related indexes. We found that E. bromicola and N, P additions positively affected seed germination. Further, E. bromicola significantly enhanced chlorophyll content and root metabolic activity under N-deficiency, and meanwhile, might alter allocation of photosynthate under different conditions. The contents of N, P and stoichiometry of C:N:P of E+ plants were significantly higher than that of E− under nutrient deficiency, but contrary results were observed under adequate nutrients. Therefore, we propose that the growth-promoting ability of E. bromicola is closely correlated with N and P additional levels. Under low N, P additions, positive roles of endophyte are significant as opposed to negative roles under high N, P additions.

Determination of Yield and Botanical Composition of the Meadow and Grassland in Çolpan Village at the Shores of Lake Van

This study was carried out at the meadows and pastures in Çolpan village of Van province in 2020. In the study, matter yield, botanical composition, plant covered area, rate of decreaser/increaser/invader species were determined. The Loop method was used to determine the botanical composition. In grassland area were identified 69 species belonging to 17 families. In meadow area were identified 20 species belonging to 6 families. The amount of Poaceae, Fabaceae and other families found in the grassland area were determined as 18.66%, 15.65%, and 65.69%, respectively. In the meadow area, the amount of Poaceae, Fabaceae and other families were determined as 67.50%, 15.0%, and 17.50%, respectively. Artemisia spicigera (4.74%) Taeniatherum caput-medusae (5.0%) Arenaria serpyllifolia (5.0%) Medicago monantha (5.92%) species were the most common species found in the grassland area. Hordeum brevisubulatum (25.5%), Bromus scoparius (16.75%), and Taraxacum androssovii (9.25%) species were the most common species found in the meadow area. According to the ratio of good plants, pasture was classified as poor pasture and meadow was in the moderate meadow class. Grassland and meadow matter yields were found to be 91.4 kg/da and 385.2 kg/da, respectively. In the grassland of Çolpan village, invader species were found to be dense. It was concluded that grassland area should be improved.

The structure of the features variability of Hordeum brevisubulatum Trin. (Link) in the middle Lena valley

The structure of variability of morphological features of perennial grass Hordeum brevisubulatum (Trin.)Link has been studied. The biological and ecological features-indicators defining the vitality state of individual andcoenopopulations of species were determined. Biological indicators are the length of the leaf sheath of the third and fourthleaves of the generative shoot and the signs of the generative sphere (inflorescence length, number of nodes and spikeletsin the inflorescence and potential seed productivity). The group of ecological features-indicators includes the number ofdifferent types of shoots in an individual.

Halophytic Hordeum brevisubulatum HbHAK1 Facilitates Potassium Retention and Contributes to Salt Tolerance

Potassium retention under saline conditions has emerged as an important determinant for salt tolerance in plants. Halophytic Hordeum brevisubulatum evolves better strategies to retain K+ to improve high-salt tolerance. Hence, uncovering K+-efficient uptake under salt stress is vital for understanding K+ homeostasis. HAK/KUP/KT transporters play important roles in promoting K+ uptake during multiple stresses. Here, we obtained nine salt-induced HAK/KUP/KT members in H. brevisubulatum with different expression patterns compared with H. vulgare through transcriptomic analysis. One member HbHAK1 showed high-affinity K+ transporter activity in athak5 to cope with low-K+ or salt stresses. The expression of HbHAK1 in yeast Cy162 strains exhibited strong activities in K+ uptake under extremely low external K+ conditions and reducing Na+ toxicity to maintain the survival of yeast cells under high-salt-stress. Comparing with the sequence of barley HvHAK1, we found that C170 and R342 in a conserved domain played pivotal roles in K+ selectivity under extremely low-K+ conditions (10 μM) and that A13 was responsible for the salt tolerance. Our findings revealed the mechanism of HbHAK1 for K+ accumulation and the significant natural adaptive sites for HAK1 activity, highlighting the potential value for crops to promote K+-uptake under stresses.