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Fagopyrum dibotrys, belonging to the family Polygonaceae and genus Fagopyrum, is used in traditional Chinese medicine and is rich in beneficial components, such as flavonoids. As its abundant medicinal value has become increasingly recognized, its excessive development poses a considerable challenge to wild germplasm resources, necessitating artificial cultivation and domestication. Considering these factors, a high-quality genome of F. dibotrys was assembled and the evolutionary relationships within Caryophyllales were compared, based on which 58 individual samples of F. dibotrys were re-sequenced. We found that the samples could be categorized into three purebred populations and regions distributed at distinct elevations. Our varieties were cultivated from the parental populations of the subpopulation in central Yunnan. F. dibotrys is speculated to have originated in the high-altitude Tibetan Plateau region, and that its combination with flavonoids can protect plants against ultraviolet radiation; this infers a subpopulation with a high accumulation of flavonoids. This study assembled a high-quality genome and provided a theoretical foundation for the future introduction, domestication, and development of cultivated varieties of F. dibotrys. [ABSTRACT FROM AUTHOR]

Modern pollen datasets are essential for pollen-based quantitative paleoclimate (e.g. precipitation) reconstructions, which can aid to better understand recent climate change and its underlying forcing mechanisms. A modern pollen dataset based on surface sediments from 90 lakes in the shrub, meadow, steppe and desert regions of the central and western Tibetan Plateau (TP) was established to fill geographical gaps left by previous datasets. Ordination analyses of pollen data and climatic parameters revealed that annual precipitation is the dominant factor for modern pollen distribution on the central and western TP. A regional transfer function for annual precipitation was developed with the weighted averaging partial least squares (WAPLS), which suggests a good inference power of the modern pollen dataset for annual precipitation. A case study in which the transfer function was effectively applied to a fossil pollen record from Lake Tangra Yumco on the central TP for paleoprecipitation reconstruction demonstrated the significance of the modern pollen dataset in less data region for paleoclimate change studies. Data from this study are openly available via the Zenodo portal (Ma et al., 2023; https://doi.org/10.5281/zenodo.8008474). [ABSTRACT FROM AUTHOR]

Endophytes in the seeds of plants have shown plant growth promoting (PGP) properties. Highland barley is an economically important crop and a major part of the local diet in the Tibetan Plateau, China, with potential health benefits. We applied culture-dependent and culture-independent methods to study endophytic bacteria in the seeds of eight Highland barley varieties. Based on the seed properties, the variety Ali was clearly separated from the other varieties except the variety CM. Most of the 86 isolates were assigned into genus Bacillus. Approximately half of the isolates showed PGP properties in vitro. Compared to the not-inoculated plants, inoculation with the isolate Bacillus tequilensis LZ-9 resulted in greater length and number of roots, and in bigger aboveground and root weights. Based on the 16S rRNA gene sequencing, the seed microbiome was majorly affiliated with the phylum Proteobacteria and the family Enterobacteriaceae. Overall, the bacterial community compositions in the different varieties were different from each other, yet the between variety differences in community composition seemed relatively small. The differences in community compositions were associated with differences in the total and reducing sugar contents and viscosity of the seeds, thus possibly connected to differences in the osmotic pressure tolerance of the endophytes. The results suggested that the seed endophytes are likely to promote the growth of Highland barley since germination. [ABSTRACT FROM AUTHOR]

The shallow seismic velocity structure of the Kunlun fault zone (KLFZ) was jointly deduced from seismic refraction profiling and the records of trapped waves that were excited by five explosions. The data were collected after the 2001 Kunlun Ms8.1 earthquake in the northern Tibetan Plateau. Seismic phases for the in-line record sections (26 records up to a distance of 15 km) along the fault zone were analysed, and 1-D P- and S-wave velocity models of shallow crust within the fault zone were determined by using the seismic refraction method. Sixteen seismic stations were deployed along the off-line profile perpendicular to the fault zone. Fault-zone trapped waves appear clearly on the record sections, which were simulated with a 3-D finite difference algorithm. Quantitative analysis of the correlation coefficients of the synthetic and observed trapped waveforms indicates that the Kunlun fault-zone width is 300 m, and S-wave quality factor Q within the fault zone is 15. Significantly, S-wave velocities within the fault zone are reduced by 30–45 per cent from surrounding rocks to a depth of at least 1–2 km, while P-wave velocities are reduced by 7–20 per cent. A fault-zone with such P- and S-low velocities is an indication of high fluid pressure because Vs is affected more than Vp. The low-velocity and low- Q zone in the KLFZ model is the effect of multiple ruptures along the fault trace of the 2001 Ms8.1 Kunlun earthquake. [ABSTRACT FROM AUTHOR]

The recent dramatic increase in seismic anisotropy and surface global positioning system (GPS) data for central Asia permits a comprehensive examination of the mantle's role in mountain building. A joint analysis of 178 shear-wave-splitting and 2000 GPS observations using a new technique reveals that the crust and lithospheric mantle deform coherently, arguing for crust-mantle mechanical coupling during deformation. The observed spatial variations in anisotropy reflect the large-scale pattern of lithospheric deformation, as well as a change in deformational style from simple shear on the Tibetan Plateau transitioning to pure shear in surrounding regions. [ABSTRACT FROM AUTHOR]