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Xia T.,CAS Northwest Institute of Plateau Biology | Xia T.,University of Chinese Academy of Sciences | Zhang L.,Sichuan Agricultural University | Xu J.,CAS Northwest Institute of Plateau Biology | And 11 more authors.
Theoretical and Applied Genetics | Year: 2017

Key message: The early flowering of Lalu was determined to be due to a novel spontaneouseam8mutation, which resulted in intron retention and the formation of a putative truncated protein. Abstract: Barley is a staple crop grown over an extensive area in the Qinghai-Tibetan Plateau. Understanding the genetic mechanism for its success in a high altitude is important for crop improvement in marginal environments. Early flowering is a critical adaptive trait that strongly influences reproductive fitness in a short growing season. Loss-of-function mutations at the circadian clock gene EARLY MATURITY 8 (EAM8) promote rapid flowering. In this study, we identified a novel, spontaneous recessive eam8 mutant with an early flowering phenotype in a Tibetan barley landrace Lalu, which is natively grown at a high altitude of approximately 4000 m asl. The co-segregation analysis in a F2 population derived from the cross Lalu (early flowering) × Diqing 1 (late flowering) confirmed that early flowering of Lalu was determined to be due to an allele at EAM8. The eam8 allele from Lalu carries an A/G alternative splicing mutation at position 3257 in intron 3, designated eam8.l; this alternative splicing event leads to intron retention and a putative truncated protein. Of the 134 sequenced barley accessions, which are primarily native to the Qinghai-Tibet Plateau, three accessions carried this mutation. The eam8.l mutation was likely to have originated in wild barley due to the presence of the Lalu haplotype in H. spontaneum from Tibet. Overall, alternative splicing has contributed to the evolution of the barley circadian clock and in the short-season adaptation of local barley germplasm. The study has also identified a novel donor of early-flowering barley which will be useful for barley improvement. © 2017, Springer-Verlag Berlin Heidelberg.

Dorji T.,Norwegian University of Life Sciences | Dorji T.,Tibet Agriculture and Animal Husbandry College | Totland o,Norwegian University of Life Sciences | Moe S.R.,Norwegian University of Life Sciences | And 3 more authors.
Global Change Biology | Year: 2013

Global climate change is predicted to have large impacts on the phenology and reproduction of alpine plants, which will have important implications for plant demography and community interactions, trophic dynamics, ecosystem energy balance, and human livelihoods. In this article we report results of a 3-year, fully factorial experimental study exploring how warming, snow addition, and their combination affect reproductive phenology, effort, and success of four alpine plant species belonging to three different life forms in a semiarid, alpine meadow ecosystem on the central Tibetan Plateau. Our results indicate that warming and snow addition change reproductive phenology and success, but responses are not uniform across species. Moreover, traits associated with resource acquisition, such as rooting depth and life history (early vs. late flowering), mediate plant phenology, and reproductive responses to changing climatic conditions. Specifically, we found that warming delayed the reproductive phenology and decreased number of inflorescences of Kobresia pygmaea C. B. Clarke, a shallow-rooted, early-flowering plant, which may be mainly constrained by upper-soil moisture availability. Because K. pygmaea is the dominant species in the alpine meadow ecosystem, these results may have important implications for ecosystem dynamics and for pastoralists and wildlife in the region. © 2012 Blackwell Publishing Ltd.

Zhang Z.-Y.,Tianjin University | Zhang Z.-Y.,Tibet Agriculture and Animal Husbandry College | Zhang Y.-P.,Tianjin University
Proceedings of the 2012 International Conference on Industrial Control and Electronics Engineering, ICICEE 2012 | Year: 2012

Mining frequent item sets is an important issue in association rules community. This paper proposes a parallel algorithm for mining frequent item sets based on bit matrix. The algorithm reduces the memory space and the I/O overhead, for it scans database only once and builds a compressed bit matrix. It combines both top-down approach and bottom-up approach to improve the efficiency of pruning, and uses dynamic scheduling parallel multi-threaded of OpenMP to mine frequent item sets. The experiments show that this algorithm has higher computing efficiency than Apriori algorithm. © 2012 IEEE.

Dorji T.,Norwegian University of Life Sciences | Totland O.,Tibet Agriculture and Animal Husbandry College | Moe S.R.,Tibet Agriculture and Animal Husbandry College
Rangeland Ecology and Management | Year: 2013

Grazing is regarded as one of the most important factors influencing rangeland ecosystems. Many previous studies have used indirect measures (proxies) of grazing intensity, such as the distance from congregation areas and the number of herbivore excreta, to estimate effects of grazing on vegetation parameters in rangeland ecosystems. However, little is known about how such proxies reflect the true grazing intensity, and if their suitability is consistent across landscape conditions. We measured grazing intensity based on the amount of plant ramets being grazed in 75 plots positioned across a rangeland landscape in central Tibet. Several grazing intensity proxies (distance from pastoral camp sites, number of yak dung patches (old and fresh), sheep and goat dropping piles, and pika (Ochotona curzoniae) burrows (active and abandoned)) were also measured in each plot. Regression models were used to examine the suitability of these proxies in predicting our measure of real grazing intensity. None of the examined proxies satisfactorily predicted real grazing intensity in our study system. The distance from camp sites was the best proxy for grazing intensity (P<0.001), but it explained only 30% of its variation. Fresh yak dung and active pika burrows explained only 10% and 3% of the variation in grazing intensity, respectively. The suitability of using proxies for grazing intensity did not significantly differ along landscape parameters (elevation, aspect directions, and slope angle) (P>0.05), except that the number of animal excreta and pika burrows functioned better as proxies at low, compared to high, elevation (P<0.05). Our results should be of concern since many studies use proxies to estimate effects of grazing on vegetation dynamics and ecosystem properties. We recommend awareness of potential limitations and suitability of proxies, when real grazing intensity is not measured. © 2013 The Society for Range Management.

Li K.,Huazhong Agricultural University | Li R.,Huazhong Agricultural University | Li R.,Nanjing University | Li J.,Huazhong Agricultural University | Li J.,Tibet Agriculture and Animal Husbandry College
Indian Journal of Animal Research | Year: 2016

Present study was an epidemiological survey for seroprevalence of Toxoplasma gondii (T. gondii) infection in pet dogs (n= 279) in Wuhan, Huazhong area of China, using indirect hemagglutination test (IHA). Overall seroprevalence of T. gondii infection in this area was 13.3 per cent. The prevalence in males and females was 13.4 and 13.0%, there was no significant difference (P≥0.05) between the genders. The prevalence of T. gondii infection was 12.7, 14.0, 13.3 and 12.7% in spring, summer, autumn and winter, respectively. There was a significant difference (P<0.05) in seroprevalence in age of pet dogs. Highest prevalence was found in older age as compared to young age pet dogs, With a prevelance rate of 7.6% in less than 1 year age dogs, and 16.7, 21.2 and 20.8%, between 1-3, 3-5 and 5 years and above, respectively. In different food spectrum (commercial dog food, combined dog food and homemade food), the prevalence of T. gondii infection is 11.4%, 13.7% and 14.5%, respectively. The seroprevalence in different breeds is ranged from 0 to 100.00%. We found T. gondii infection in pet dogs in Wuhan, which can adversely affect community health in this region. To the best of our knowledge, this is the first report of the prevalence of T. gondii infection in pet dogs in Wuhan. © 2016, Agricultural Research Communication Centre. All rights reserved.

Lu J.,Institute of Plateau Ecology | Lu J.,National Forest Ecosystem Observation and Research Station of Tibet Linzhi | Lan X.-Z.,Tibet Agriculture and Animal Husbandry College
Zhongguo Zhongyao Zazhi | Year: 2013

Objective: To investigate and study the endangered Tibetan medicinal plant species, their moisture content, bio-mass and resources reserves in Lhasa region. Method: The rare and endangered Tibetan medicinal plant resources were investigated by plot-quadrat method, walking and inquiry ways, sampling and drying method. Result: There were 37 species of rare and endangered plants, belonging to 22 families and 34 genera in Lhasa region. The moisture content of aerial part was higher than that of underground part in many plants. The moisture content of Przewalskia tangutica was the highest (91.97%), and the lowest one was Fritillaria delavayi (only 25.99%). The mean biomass of Rubus biflorus was the highest (1830.480 g), that of Cordyceps sinensis was the lowest (0.291 g). The root-shoot ratio of Asparagus filicinus was the maximum (5.313), the minimum was Aconitum gymnandrum (0.286). The largest output was 18.000 kg · hm-2 for Berberis agricola, the output of Saxifraga pasumensis was the lowest (0.007 kg · hm-2). The resources reserves of the rare and endangered plants were 15683.697 t in Lhasa region, the maximum was 7690.230 t for B. agricola, 49.03% of the total reserves, the minimum was 2.393 t for S. pasumensis, only 0.015%. Conclusion: The characteristics of rare and endangered plants were as follows: abundant species and complex habitats, widely distribution but uneven, rich reserves and high economic value. We suggested to update the endangered level of medicinal plants, strengthen the scientific research on these plants, maintain sustainable utilization of the rare and endangered plants in Lhasa region.

Wang J.,CAS Beijing Institute of Geographic Sciences and Nature Resources Research | Zhang X.-Z.,CAS Beijing Institute of Geographic Sciences and Nature Resources Research | Zhao Y.-P.,CAS Beijing Institute of Geographic Sciences and Nature Resources Research | Zhao Y.-P.,University of Chinese Academy of Sciences | And 3 more authors.
Chinese Journal of Applied Ecology | Year: 2010

Based on the meteorological data and remote sensing data, and by using vegetation-climate comprehensive model and CASA model, this paper analyzed the climate change trend and the spatiotemporal pattern of alpine grassland potential and actual net primary productivity (NPP) in Qiantang Plateau. In 1955-2004, the mean annual temperature and annual cumulated precipitation in the Plateau increased by 1. 37 °C and 63 mm, respectively. The climate in the central and eastern parts of the Plateau became warmer and wetter, whereas it was warmer and dryer in the western part. However, the regional climate change did not yet result in grassland degradation. The mean potential NPP of alpine grassland was in the order of eastern part > central part > western part. From 1982 to 2004, the potential NPP in the central part had the largest increment (0. 55 t • hm -2 • a -1), followed by in the eastern part (0. 51 t • hm -2 • a -1) and western part (0. 21 t • hm -2 • a -1), which was consequent with the spatiotemporal pattern of climate change in the study area. In contrast, the actual NPP in the eastern, central, and western parts in the past two decades was-0. 19,-0. 03, and 0. 20 t • hm -1 • a -1, respectively. Overgrazing was the main reason of grassland degradation in the central and eastern parts, and the central part was the key layout area for the implement of 'grazing withdrawal and management of grassland' project.

Tian W.-M.,Chinese Academy of Sciences | Zhang H.,Tibet Agriculture and Animal Husbandry College | Yang S.-G.,Chinese Academy of Sciences | Shi M.-J.,Chinese Academy of Sciences | And 3 more authors.
Journal of Plant Physiology | Year: 2013

Tapping causes the loss of large amounts of latex from laticifers and subsequently enhances latex regeneration, a high carbon- and nitrogen-cost activity in rubber tree. It is suggested that a 67. kDa protein associated with protein-storing cells in the inner bark tissues of rubber tree plays an important role in meeting the nitrogen demand for latex regeneration. Here, the 67. kDa protein was further characterized by a combination of cell biological, molecular biological and biochemical techniques. Immunogold labeling showed that the 67. kDa protein was specifically localized in the central vacuole of protein-storing cells. A full-length cDNA, referred to as HbVSP1, was cloned. The HbVSP1 contained a 1584. bp open reading frame encoding a protein of 527 amino acids. The putative protein HbVSP1 shared high identity with the P66 protein from rubber tree and proteins of the linamarase, and bg1A from cassava (Manihot esculenta). HbVSP1 contained the active site sequences of β-glucosidase, TFNEP and I/VTENG. In vitro analysis showed that the 67. kDa protein exhibited the activity of both β-glucosidase and linamarase and was thus characterized as a cyanogenic β-glucosidase. Proteins immuno-related to the 67. kDa protein were present in leaves and lutoids of laticifers. Tapping down-regulated the expression of HbVSP1, but up-regulated the expression of genes encoding the key enzymes for rubber biosynthesis, while the effect of resting from tapping was the reverse. Taken together, the results suggest that the 67. kDa protein is a vacuole-localized cyanogenic β-glucosidase encoded by HbVSP1 and may have a role in nitrogen storage in inner bark tissues of trunk during the leafless periods when rubber tree is rested from tapping. © 2013 Elsevier GmbH.

Ma H.-P.,Research Institute of Plateau Ecology | Yang X.-L.,Tibet Agriculture and Animal Husbandry College | Guo Q.-Q.,Research Institute of Plateau Ecology | Zhang X.-J.,Research Institute of Plateau Ecology | Zhou C.-N.,Research Institute of Plateau Ecology
Journal of Mountain Science | Year: 2016

Labile organic carbon (LOC) is one of the most important indicators of soil organic matter quality and dynamics elevation and plays important function in the Tibetan Plateau climate. However, it is unknown what the sources and causes of LOC contamination are. In this study, soil organic carbon (SOC), total nitrogen (TN), microbial biomass carbon (MBC), microbial biomass nitrogen (MBN) and LOC were analyzed based on different soil horizons and elevations using turnover time in an experimental site (3700 m to 4300 m area) in Sygera. SOC and LOC in higher-elevation vegetation types were higher than that of in lower-elevation vegetation types. Our results presented that the soil microbial biomass carbon (SMBC) and soil microbial biomass nitrogen (SMBN) were positively correlated with SOC. The content of easily oxidized carbon (EOC), particulate organic carbon (POC) and light fraction organic carbon (LFOC) decreased with depth increasing and the content were the lowest in the 60 cm to 100 cm depth. The total SOC, ROC and POC contents decreased with increasing soil horizons. The SOC, TN, MBC and MBN contents increased with increasing altitude in the Sygera Mountains. The MBC and MBN contents were different with the changes of SOC (p<0.05), meanwhile, both LFOC and POC were related to total SOC (p<0.05). The physical and chemical properties of soil, including temperature, humidity, and altitude, were involved in the regulation of SOC, TN, MBC, MBN and LFOC contents in the Sygera Mountains, Tibetan Plateau. © 2016, Science Press, Institute of Mountain Hazards and Environment, CAS and Springer-Verlag Berlin Heidelberg.

Ma H.,Research Institute of Plateau Ecology | Guo Q.,Research Institute of Plateau Ecology | Liu H.,Tibet Agriculture and Animal Husbandry College | Qian D.,Tibet Agriculture and Animal Husbandry College
Shengtai Xuebao/ Acta Ecologica Sinica | Year: 2013

AS a key component of ecosystem carbon budgets, soil carbon is the largest carbon pool of forest ecosystem. Soil microbial biomass carbon is an important component of carbon cycle of the terrestrial ecosystem. In order to explore the effects of different forest types on soil active carbon pool, we chosed Alpine Shrub AS,Rhododendron Forest RF,Abies georgei var. smithii forest AGSF and Picea likiangensis var. linzhiensis forest PLLF as experimental sites in the Sygera Mountainous southeast Tibet. Soil organic carbon SOC, total nitrogen TN and soil microbial biomass were studied at different soil horizon. There is higher LOC(labile organic carbon) at higher-elevation vegetation types in comparison with lower-elevation ones. At 0-10cm soil layer, SOC among the AS, RF, AGST and PLLF were significantly different P< 0.05. However, no trend was found for SOC at 10-20cm and 20-40cm. At the AS site, TN were significantly different at 0-10cm soil layer P<0. 05. There were no significant difference for the AS, RF, AGST and PLLF sites P<0. 05. At 10-20cm soil layer, there were significant difference for them(P<0. 05). However, no regularity was found for SOC at 20-40cm. At different depths, the soil microbial biomass was significantly correlated to soil organic carbon. The SMBC and SMBN was positively correlated with SOC, and the SMBN or its ratio was also positively correlated with the SMBC content and its ratio. The SMBC and SMBN increase with increasing elevationt in the Sygera Mountains. As shown, the total SOC, readily oxidizable carbon and particulate organic carbon decreased with increasing soil horizons. The rations of particulate organic carbon to total SOC content and the readily oxidizable carbon to total SOC content were different in their range. Moreover, their ratios decreased with increasing soil horizons. The active SOC was significantly related to total SOC. In addition, the relationship between readily oxidizable carbon and particulate organic carbon was also significant P<0. 05.

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