Identification of stable quantitative trait loci underlying waterlogging tolerance post-anthesis in common wheat(Triticum aestivum)

Waterlogging is a growing threat to wheat production in high-rainfall areas.In this study,a doubled haploid(DH) population developed from a cross between Yangmai 16(waterlogging-tolerant) and Zhongmai895(waterlogging-sensitive) was used to map quantitative trait loci(QTL) for waterlogging tolerance using a high-density 660K single-nucleotide polymorphism(SNP) array.Two experimental designs,waterlogging concrete tank(CT) and waterlogging plastic tank(PT),were used to simulate waterlogging during anthesis in five environments across three growing seasons.Waterlogging significantly decreased thousand-kernel weight(TKW) relative to non-waterlogged controls,although the degree varied across lines.Three QTL for waterlogging tolerance were identified on chromosomes 4AL,5AS,and 7DL in at least two environments.All favorable alleles were contributed by the waterlogging-tolerant parent Yangmai16.QWTC.caas-4AL exhibited pleiotropic effects on both enhancing waterlogging tolerance and decreasing plant height.Six high-confidence genes were annotated within the QTL interval.The combined effects of QWTC.caas-4AL and QWTC.caas-5AS greatly improved waterlogging tolerance,while the combined effects of all three identified QTL(QWTC.caas-4AL,QWTC.caas-5AS,and QWTC.caas-7DL) exhibited the most significant effect on waterlogging tolerance.Breeder-friendly kompetitive allele-specific PCR(KASP) markers(K_AX_111523809,K_AX_108971224,and K_AX_110553316) flanking the interval of QWTC.caas-4AL,QWTC.caas-5AS,and QWTC.caas-7DL were produced.These markers were tested in a collection of 240 wheat accessions,and three superior polymorphisms of the markers distributed over 67elite cultivars in the test population,from the Chinese provinces of Jiangsu,Anhui,and Hubei.The three KASP markers could be used for marker-assisted selection(MAS) to improve waterlogging tolerance in wheat.

对乙酰氨基酚联合外照射对脑胶质瘤细胞照射后代增殖的影响(英文)

Objective:To study the effects of acetaminophen(ACE) combined with radiation on the progeny of the human glioma cell line SHG-44,and to investigate if ACE may be an useful therapeutic radiosensitivity agent in the treatment of recurrent human glioma.Methods:A randomized,controlled experiment,was performed at the Department of Radiology Laboratory,the First Hospital Affiliated to Soochow University,between September 2004 and January 2006.Brain glioma SHG-44 cells were divided into three groups:SHG-44,SHG-44-10,and SHG-44-10 + ACE cells groups.The SHG-44-10 cells group was irradiated with dose of 10 Gy by a linear accelerator(6 MVX).It was passaged for 15 generations and cultured in RPMI-1640 culture media.Then SHG-44-10 + ACE cells group was treated with ACE.Measures:Community re-double time,mean lethal dose(D0),extrapolation number(N),fraction surviving fraction irradiated by 2 Gy dose(SF2),quasi-threshold dose(Dq),and cell cycle.Results:The SF2 of the SHG-44,SHG-44-10,and SHG-44-10 + ACE cells groups were 70.8%,80.6% and 45.2%,respectively,with significance(P = 0.040).The SHG-44-10 and SHG-44-10 + ACE cells groups were irradiated with 8 Gy.After 12 hours,the G2/M ratio of the SHG-44-10 and SHG-44-10 + ACE cells groups were indicating significantly higher ratio compared to pre-irradiated groups(P < 0.01).After 24 hours,the G2/M ratio of the SHG-44-10 cells group decreased rapidly,while the ratio of the SHG-44-10 + ACE cells group still maintained in high level.Conclusion:In the present study,Subtoxic dose of ACE increased the radiosensitivity of the progeny of irradiated human glioma cell.ACE may be an useful radiosensitivity agent in the treatment of recrudescent human malignant glioma.

A chromosome-scale reference genome of Lobularia maritima,an ornamental plant with high stress tolerance

Lobularia maritima(L.)Desv.is an ornamental plant cultivated across the world.It belongs to the family Brassicaceae and can tolerate dry,poor and contaminated habitats.Here,we present a chromosome-scale,high-quality genome assembly of L.maritima based on integrated approaches combining Illumina short reads and Hi–C chromosome conformation data.The genome was assembled into 12 pseudochromosomes with a 197.70 Mb length,and it includes 25,813 protein-coding genes.Approximately 41.94%of the genome consists of repetitive sequences,with abundant long terminal repeat transposable elements.Comparative genomic analysis confirmed that L.maritima underwent a species-specific whole-genome duplication(WGD)event~22.99 million years ago.We identified~1900 species-specific genes,25 expanded gene families,and 50 positively selected genes in L.maritima.Functional annotations of these genes indicated that they are mainly related to stress tolerance.These results provide new insights into the stress tolerance of L.maritima,and this genomic resource will be valuable for further genetic improvement of this important ornamental plant.

Discussion on Mode of Key Link in Increase and Decrease Connection of Urban and Rural Construction Land

With the methods of qualitative analysis, induction and deduction, modes of key links in increase and decrease connection of urban and rural construction land are proposed in view of the involved three key links, namely reclamation of rural construction land, fund raising and management of connection turnover index, based on the comprehensive analysis of political connotation in increase and decrease of urban and rural construction land. The modes include "village relocation and combination", "hollow village" reconstruction, high-rise stereo, village relocation in the mountain and related capital raising and turnover index management and the applicable regions of various modes are analyzed and studied. The research result provides reference for the reasonable operation of increase and decrease link of urban and rural construction land.

Global multifaceted biodiversity patterns,centers,and conservation needs in angiosperms

The Convention on Biological Diversity seeks to conserve at least 30%of global land and water areas by 2030,which is a challenge but also an opportunity to better preserve biodiversity,including flowering plants(angiosperms).Herein,we compiled a large database on distributions of over 300,000 angiosperm species and the key functional traits of 67,024 species.Using this database,we constructed biodiversity-environment models to predict global patterns of taxonomic,phylogenetic,and functional diversity in terrestrial angiosperms and provide a comprehensive mapping of the three diversity facets.We further evaluated the current protection status of the biodiversity centers of these diversity facets.Our results showed that geographical patterns of the three facets of plant diversity exhibited substantial spatial mismatches and nonoverlapping conservation priorities.Idiosyncratic centers of functional diversity,particularly of herbaceous species,were primarily distributed in temperate regions and under weaker protection compared with other biodiversity centers of taxonomic and phylogenetic facets.Our global assessment of multifaceted biodiversity patterns and centers highlights the insufficiency and unbalanced conservation among the three diversity facets and the two growth forms(woody vs.herbaceous),thus providing directions for guiding the future conservation of global plant diversity.

Phylotranscriptomics of Swertiinae(Gentianaceae)reveals that key floral traits are not phylogenetically correlated

Establishing how lineages with similar traits are phylogenetically related remains critical for understanding the origin of biodiversity on Earth.Floral traits in plants are widely used to explore phylogenetic relationships and to delineate taxonomic groups.The subtribe Swertiinae(Gentianaceae)comprises more than 350 species with high floral diversity ranging from rotate to tubular corollas and possessing diverse nectaries.Here we performed phylogenetic analysis of 60 species from all 15 genera of the subtribe Swertiinae sensu Ho and Liu,representing the range of floral diversity,using data from the nuclear and plastid genomes.Extensive topological conflicts were present between the nuclear and plastome trees.Three of the 15 genera represented by multiple species are polyphyletic in both trees.Key floral traits including corolla type,absence or presence of lobe scales,nectary type,nectary position,and stigma type are randomly distributed in the nuclear and plastome trees without phylogenetic correlation.We also revealed the likely ancient hybrid origin of one large clade comprising 10 genera with diverse floral traits.These results highlight the complex evolutionary history of this subtribe.The phylogenies constructed here provide a basic framework for further exploring the ecological and genetic mechanisms underlying both species diversification and floral diversity.

Spatiotemporal variation in leaf size and shape in response to climate

叶片的形态变异是研究植物响应气候变化的重要指标之一。叶片大小与形状影响着植物与外界环境的碳、水等物质交换和能量交换。然而,叶片大小与形状如何响应气候变化仍缺乏研究。此外,大多研究忽略了叶大小与形状在时间和空间上的种内变异,而只关注种间变异。我们收集了中国98年(1910-2008年)7个代表性双子叶植物的植物标本馆标本6000多份,并测量了它们叶片的叶长和宽度。我们探索了叶片大小(叶长、叶宽和长×宽乘积)的地理模式和时间趋势,即研究了降水量和温度随时间和空间的变化对叶片大小和形状变化的影响。在控制了标本采集时间的影响后,全部物种的平均叶大小沿着纬度梯度的增加而减小,但这一关系在不同物种间存在差异。叶大小和形状的空间变异与温度和降水正相关。当控制了采集地点的影响后,全部物种的平均叶大小随着时间有变大的趋势。大多数物种叶大小的时间变化与降水正相关,而叶形状的时间变化则与温度正相关。我们的研究指出叶大小和形状在时空上的种内变异显著受气候的影响,同时说明植物标本可以为研究植物形态对气候变化的响应提供素材。

Patterns and ecological determinants of woody plant height in eastern Eurasia and its relation to primary productivity

Aims Plant height is a key functional trait related to aboveground bio-mass,leaf photosynthesis and plant fitness.However,large-scale geographical patterns in community-average plant height(cAPH)of woody species and drivers of these patterns across different life forms remain hotly debated.Moreover,whether cAPH could be used as a predictor of ecosystem primary productivity is unknown.Methods We compiled mature height and distributions of 11422 woody spe-cies in eastern Eurasia,and estimated geographic patterns in cAPH for different taxonomic groups and life forms.then we evaluated the effects of environmental(including current climate and historical climate change since the Last Glacial Maximum(LGM))and evolutionary factors on cAPH.Lastly,we compared the predictive power of cAPH on primary productivity with that of LiDAR-derived canopy-height data from a global survey.Important Findings Geographic patterns of cAPH and their drivers differed among taxonomic groups and life forms.the strongest predictor for cAPH of all woody species combined,angiosperms,all dicots and deciduous dicots was actual evapotranspiration,while temperature was the strongest pre-dictor for cAPH of monocots and tree,shrub and evergreen dicots,and water availability for gymnosperms.Historical climate change since the LGM had only weak effects on cAPH.No phylogenetic signal was detected in family-wise average height,which was also unrelated to the tested environmental factors.Finally,we found a strong correlation between cAPH and ecosystem primary productivity.Primary productivity showed a weaker relationship with cAPH of the tallest species within a grid cell and no relationship with LiDAR-derived canopy height reported in the global survey.Our findings suggest that current climate rather than historical climate change and evolutionary history determine the geographical patterns in cAPH.However,the relative effects of climatic factors representing environmental energy and water availability on spatial variations of cAPH vary among plant life forms.Moreover,our results also suggest that cAPH can be used as a good predictor of ecosystem primary productivity.

北半球高山和极地虎耳草属物种丰富度的地理格局:温度和生境异质性的作用

现代气候、生境异质性和长期气候变化对森林生态系统中分布的木本植物的物种丰富度格局的影响在以往研究中受到广泛关注,但对高寒-极地生态系统中的草本植物物种丰富度格局及其影响因素的研究仍较少。本研究旨在检验以往研究中基于物种丰富度和环境因子关系提出的假说是否能够解释高寒-极地地区典型草本植物-虎耳草属(Saxifraga)的物种丰富度格局。本研究利用全球437种虎耳草属物种分布数据,探讨了全部物种、广域和狭域物种丰富度格局的影响因素。采用广义线性模型和空间自回归模型,评估了现代气候、生境异质性和历史气候对虎耳草属物种丰富度格局的影响。采用偏回归分析了不同变量对物种丰富度的独立解释率和共同解释率,并检验了4种广泛使用的物种丰富度与环境关系模型对物种丰富度格局的解释能力。研究结果表明,温度与虎耳草属所有物种和广域物种的物种丰富度格局呈显著负相关关系,是影响物种丰富度格局最重要的环境因子,这可能反映了虎耳草属对其祖先温带生态位的保守性。生境异质性和末次冰期以来的气候变化是虎耳草属狭域物种丰富度空间变异的最佳预测因子。总体而言,包含5个预测变量的组合模型可以解释大约40%–50%的虎耳草属物种丰富度的空间变异。此外,进化和生物地理过程在虎耳草属物种丰富度格局形成方面可能发挥了重要作用,这有待进一步研究。

中国桑科植物物种多样性格局及其主导因子

理解物种多样性大尺度格局及其驱动机制是生态学的核心议题之一。以往研究已提出了多种解释物种多样性格局的假说,其中包括水热动态假说、热带生态位保守假说、Janzen假说以及包含能量、水分、季节性和生境异质性的综合假说,但各假说对不同类别(如不同生活型、不同分布区大小的物种)植物物种多样性格局的相对贡献仍存在争议,这阻碍了我们理解驱动物种多样性格局形成的一般规律。本研究以桑科植物为对象,评估了以上假说对不同类别桑科植物物种多样性格局的相对影响。我们收集整理了中国164种桑科植物的物种分布图(空间分辨率50 km×50 km)及其生活型(即灌木、小乔木和大乔木)。在此基础上,估算了整个科、不同生活型以及不同分布区大小物种(广域种和狭域种)的物种多样性格局,分析了环境变量对物种多样性格局的影响,比较了不同假说对各类别桑科植物物种多样性格局的相对解释率。不同类别桑科植物的物种多样性格局高度一致,四川省、广州省和海南省的物种多样性较高,形成了该科物种多样性热点。气候季节性是桑科物种多样性格局的主导因素。在所有假说中,包含能量、水分、季节性和生境异质性的综合假说对不同生活型和不同分布区大小物种的多样性格局具有最高的解释率。需要指出的是,对除狭域种外的其他所有物种组的物种多样性格局来说,这些模型均具有较高的共享解释率,但较低的独立解释率(<5%)。这些结果说明,与其他物种组相比,狭域种物种多样性格局及其形成机制可能是不同的。本研究为保护桑科植物、特别是狭域桑科植物提供了理论依据。