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New insights into the carotenoid biosynthesis in Torreya grandis kernels 被引量:1
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作者 Jingwei Yan Hao Zeng +4 位作者 Weijie Chen Jiali Luo Congcong Kong Heqiang Lou Jiasheng Wu 《Horticultural Plant Journal》 SCIE CAS CSCD 2023年第6期1108-1118,共11页
Torreya grandis is a characteristic rare economic tree species in subtropical mountainous areas. The nut has a variety of bioactive compounds, such as polyphenols and vitamins. However, the carotenoids compositions an... Torreya grandis is a characteristic rare economic tree species in subtropical mountainous areas. The nut has a variety of bioactive compounds, such as polyphenols and vitamins. However, the carotenoids compositions and its regulatory mechanisms underlying carotenoid biosynthesis in kernels remain unknown. Here, the major carotenoids in the kernel were analyzed. The result showed that lutein and β-carotene were the predominant carotenoids in the kernel, while low levels of a-carotenoid and zeaxanthin were detected. Lutein and β-carotene were decreased during the maturation of kernel. Expression analysis by RNA-seq and q RT-PCR indicated that the expressions of TgCYP97A3 and TgLCYB were also reduced during the maturation of kernel. The contents of lutein or β-carotene were obviously increased in tobacco transiently overexpressing TgCYP97A3 or TgLCYB. Moreover, DPPH radical scavenging activity and FRAP were also significantly enhanced. In addition, several MYB and WRKY transcription factors TgMYBS3, TgMYB48 and TgWRKY11 were identified to positively regulate the TgCYP97A3 expression, while TgMYB48, TgWRKY2 and TgWRKY11 could upregulate the TgLCYB expression. The illustration of carotenoids biosynthesis and its molecular mechanism in kernels not only provides a basis for understanding carotenoids biosynthesis in kernels, but also enables the use of molecular biotechnology to develop new health products rich in carotenoids based on T. grandis nuts. 展开更多
关键词 Torreya grandis KERNEL LUTEIN b-carotene TgCYP97A3 TgLCYB
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Effect of slope position on leaf and fine root C,N and P stoichiometry and rhizosphere soil properties in Tectona grandis plantations
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作者 Qingqing Zhang Zaizhi Zhou +4 位作者 Weiwei Zhao Guihua Huang Gaofeng Liu Xiaofei Li Junduo Wu 《Journal of Forestry Research》 SCIE CAS CSCD 2023年第6期1997-2009,共13页
Little is known about C-N-P stoichiometries and content in teak(Tectona grandis)plantations in South China,which are mostly sited on hilly areas with lateritic soil,and the effect of slope position on the accumulation... Little is known about C-N-P stoichiometries and content in teak(Tectona grandis)plantations in South China,which are mostly sited on hilly areas with lateritic soil,and the effect of slope position on the accumulation of these elements in trees and rhizosphere soils.Here we analyzed the C,N,P content and stoichiometry in leaves,fine roots and rhizosphere soils of trees on the upper and lower slopes of a 12-year-old teak plantation.The Kraft classification system of tree status was used to sample dominant,subdominant and mean trees at each slope position.The results showed that the C,N and P contents in leaves were higher than in fine roots and rhizosphere soils.The lowest C/N,C/P and N/P ratios were found in rhizosphere soils,and the C/N and C/P ratios in fine roots were higher than in leaves.Nutrient accumulation in leaves,fine roots and rhizosphere soils were significantly influenced by slope position and tree class with their interaction mainly showing a greater effect on rhizosphere soils.Leaf C content and C/N ratio,fine root C and P contents,and C/N and C/P ratios all increased distinctly with declining slope position.The contents of organic matter(SOM),ammonium(NH4+-N),nitrate-nitrogen(NO3--N)and available potassium(AK)in rhizosphere soils were mainly enriched on upper slopes,but exchange calcium(ECa),available phosphorus(AP),and pH were relatively lower.Variations in the C,N and P stoichiometries in trees were mainly attributed to the differences in rhizosphere soil properties.N and P contents showed significant positive linear relationships between leaf and rhizosphere soil,and C content negative linear correlation among leaves,fine roots and rhizosphere soils.Chemical properties of rhizosphere soils,particularly C/N and NH4+-N,had significant effects on the leaf nutrients in trees on the upper slope.Correspondingly,rhizosphere soil properties mainly influenced fine root nutrients on the lower slope,and soil AK was the major influencing factor.Overall,these results offer new insights for the sustainability and management of teak plantations in hilly areas. 展开更多
关键词 Tectona grandis Stoichiometric ratio Rhizosphere soil Dominant trees Nutrient accumulation
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Understory plant diversity and phenolic allelochemicals across a range of Eucalyptus grandis plantation ages
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作者 Jinjin Li Yumei Huang +3 位作者 Lianghua Chen Shun Gao Jian Zhang Danju Zhang 《Journal of Forestry Research》 SCIE CAS CSCD 2023年第5期1577-1590,共14页
Allelopathy is an important mechanism in Eucalyptus plantations that causes detrimental impacts on understory diversity.Phenolic compounds are the main allelochemicals suppressing understory plants.However,the dynamic... Allelopathy is an important mechanism in Eucalyptus plantations that causes detrimental impacts on understory diversity.Phenolic compounds are the main allelochemicals suppressing understory plants.However,the dynamic changes in phenolic allelochemicals and their relationship with understory diversity with increasing age of Eucalyptus plantations remain largely unclear.In this study,the understory plant diversity was assessed and phenolic compounds identified from leaf litter,roots,and rhizosphere soil samples in a Eucalyptus grandis plantation at two-year intervals for ten years using ultra-performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS).The abundance and diversity of under story plant species were lowest in 4-year-old plantations and increased significantly with age.Seven phenolic acids and 10 flavonoids were identified from leaf litter,roots,and rhizosphere soils.Most of the potential phenolic allelochemicals,such as salicylic acid,gallic acid,4-hydroxybenzoic acid,and epicatechin,were more abundant in younger plantations,especially at4 years old.The concentrations of phenolic compounds in the rhizosphere zone were significantly lower than in litter and root samples and did not change significantly with an increase in age.Notably,phenolic compounds contributed more to the variation in the understory plants than soil factors.Hydroxyphenyllactic acid,ellagic acid,quercetin,salicylic acid,and 4-hydroxybenzoic acid were the main phenolic compounds explaining the variation in plant diversity with plantation age.These findings indicate that young E.grandis plantations,especially at four years of age,merit a greater focus because of their lower understory plant diversity and higher allelopathic potential. 展开更多
关键词 Eucalyptus grandis Phenolic compounds Understory plant diversity Plantation age
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Tectona grandis (Teak Tree) Young Leaf Extract as a Histological Stain
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作者 Cecilia Smith-Togobo Adam Abdul Fatau +4 位作者 Magalys Cuba Lopez Felix Kpor David Larbi Simpong George Osei Yiadom Emmanuel Akomanin Asiamah 《Journal of Biomedical Science and Engineering》 CAS 2023年第2期17-41,共25页
Stains are applied to impart contrast to the tissue and identify particular features of interest. However, the use of synthetic dyes as staining reagents has been associated with significant human health challenges an... Stains are applied to impart contrast to the tissue and identify particular features of interest. However, the use of synthetic dyes as staining reagents has been associated with significant human health challenges and pollution of the ecosystem. These developments have necessitated a shift towards using natural dyes that are eco-friendlier and readily available. We investigated the staining reaction patterns of teak tree leaves (Tectona grandis) dye extracts and explored their suitability as a cytoplasmic stain in micromorphological assessments. Dye extracts were prepared using acetone, methanol, and ethanol as solvents from air-dried (under shade) teak tree young leaves. The dye extracts were applied as a counterstain and evaluated against eosin in formalin-fixed paraffin-embedded (FFPE) bovine tissue sections at varying concentrations and different staining times. Teak tree leaves (Tectona grandis) dye extracts produced relatively varying staining intensities of reddish-brown cytoplasmic coloration when used on bovine tissue at different concentrations and staining times comparable to eosin and with blue-purple hematoxylin nuclear stain. The present study showed that Tectona grandis leaf dye extracts provide an excellent cytoplasmic staining pattern and can be used as an alternative counterstain in routine H&E staining techniques. 展开更多
关键词 Histology CYTOPLASM Plant Extract Tectona grandis Leaves Formalin-Fixed Paraffin-Embedded Tissues Natural Dye STAINING Cytoplasmic Stain Animal Tissues Staining Reaction
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Effects of Torreya grandis Root Rot on Seedling Growth and Screening of Its Chemical Control Agents
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作者 Lei ZHENG Xinyu RU +5 位作者 Ziyi WAN Chao HE Xiaoyu LI Caiyun LYU Li CHEN Zhibing WAN 《Agricultural Biotechnology》 CAS 2023年第5期108-113,共6页
[Objectives]This study was conducted to prevent the occurrence of root rot disease in Torreya grandis and improve the yield and quality of T.grandis.[Methods]One-year-old and two-year-old seedlings of Torreya grandis... [Objectives]This study was conducted to prevent the occurrence of root rot disease in Torreya grandis and improve the yield and quality of T.grandis.[Methods]One-year-old and two-year-old seedlings of Torreya grandis‘Xifei’and‘Cufei’were inoculated with the root rot pathogen Fusarium fujikuroi,and the changes in photosynthesis,chlorophyll content,malondialdehyde,and defense enzyme system(superoxide dismutase,peroxidase,and catalase)activity in leaves of T.grandis seedlings were investigated using water as a control.Meanwhile,the control effects of 80%carbendazim wettable powder,64%metalaxyl·mancozeb wettable powder,430 g/L tebuconazole suspension and 30%difenoconazole·cyproconazole EC on root rot in T.grandis were investigated.[Results]After inoculation with the pathogen F.fujikuroi,the net photosynthetic rates and transpiration rates in leaves of T.grandis‘Xifei’and‘Cufei’decreased,and the contents of chlorophyll decreased,while the contents of malondialdehyde increased,and the contents of superoxide dismutase and catalase increased with time.However,peroxidase showed a high activity in T.grandis‘Cufei’only,but a trend of"increasing-decreasing-increasing"in T.grandis‘Xifei’.Among the four chemical control agents,64%metalaxyl·mancozeb wettable powder had the best control effect on root rot of T.grandis caused by the pathogenic fungus F.fujikuroi.[Conclusions]The net photosynthetic rate,transpiration rate,chlorophyll content,malondialdehyde content,superoxide dismutase activity and catalase activity could all be used as screening indicators for T.grandis varieties resistant to root rot.Meanwhile,64%metalaxyl·mancozeb wettable powder could be used as a control agent for root rot on T.grandis. 展开更多
关键词 Torreya grandis Root rot disease Physiological and biochemical metabolism Chemical control
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巨桉(Eucalyptus grandis)人工林土壤动物群落对采伐干扰的初期响应 被引量:22
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作者 肖玖金 张健 +4 位作者 杨万勤 黄玉梅 杨鲁 李纪伟 严妲 《生态学报》 CAS CSCD 北大核心 2008年第9期4531-4539,共9页
为了解采伐干扰对巨桉(Eucalyptus grandis)人工林土壤动物的影响,于2005~2007年采用手捡法和干湿漏斗法对四川省洪雅县巨桉人工林采伐干扰前和采伐干扰后土壤动物群落进行调查,采伐干扰前四季共获土壤动物4775头,分属4门11纲27目,... 为了解采伐干扰对巨桉(Eucalyptus grandis)人工林土壤动物的影响,于2005~2007年采用手捡法和干湿漏斗法对四川省洪雅县巨桉人工林采伐干扰前和采伐干扰后土壤动物群落进行调查,采伐干扰前四季共获土壤动物4775头,分属4门11纲27目,采伐干扰后获土壤动物4640头,分属4门10纲23目。采伐干扰后秋季(10月)、冬季(1月)和春季(4月)土壤动物个体数较采伐干扰前分别上升224头、368头和443头,而夏季(7月)下降了1170头。采伐干扰前巨桉人工林土壤动物个体数与类群数季节变化趋势基本一致,而采伐干扰后土壤动物类群数变化受土壤动物个体数变化的影响较小。与采伐干扰前相比,采伐干扰后枯落物层各季节土壤动物密度均低于采伐前,0~5 cm土层土壤动物密度与干扰前呈相反的变化趋势,其波动较5~10 cm和10~15 cm土层大。采伐干扰后土壤动物类群数四季共减少4个,采伐干扰前后土壤动物优势类群类群数波动小,采伐后常见类群类群数上升(除冬季外),稀有类群对采伐干扰较敏感,其类群数下降幅度较大。采伐干扰前后同功能种团均以杂食性和腐食性土壤动物为主,两者百分比之和均在89%以上。密度-类群指数(DG)和多样性指数(H′)的变化趋势相似,采伐干扰前后的变化趋势相反,表明采伐干扰对巨桉人工林土壤动物季节变化有较大影响。 展开更多
关键词 采伐干扰 巨桉(Eucalyptus grandis)人工林 土壤动物 群落
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A Study of the Distribution and Accumulation of Major Nutrient Elements in Different Densities of Eucalyptus grandis 被引量:5
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作者 王丽 龙汉利 +3 位作者 郭洪英 辜云杰 肖兴翠 盛玉珍 《Agricultural Science & Technology》 CAS 2017年第6期1062-1066,共5页
This study was conducted to investigate the distribution and accumulation of major elements of 5-year-old Eucalyptus grandis forests with the densities of 556 trees/hm2 and 1 667 trees/hm2. The results showed that: ... This study was conducted to investigate the distribution and accumulation of major elements of 5-year-old Eucalyptus grandis forests with the densities of 556 trees/hm2 and 1 667 trees/hm2. The results showed that: (1) The distribution of ma- jor nutrient element contents in various organs of the E. grandis with the 2 densi- ties was nearly the same, and the ranked order was leaf〉tree trunk〉branch or branchlet〉fruit〉bark. (2) From the distribution of nutrient elements and organic mat- ter in the trunk, P, K, Mg and Ca contents presented basically a trend of increasing with the trunk height increasing. And the organic matter content increased with the trunk height increasing in the low density stand, while the result was opposite in the high density stand. Furthermore, N content increased with the trunk height increas- ing in the low density stand, but the content in the high density stand exhibited a trend of decreasing at first, increasing then and increasing at the last. (3) From the distribution of biomass, the ranked order was tree trunk〉bark or branch〉branchlet〉 leaf〉fruit. And (4) The accumulated amounts of major nutrient elements in various organs under the 2 stand densities was nearly same. Ca content was the highest in the 2 kinds of plantations, followed by N, K, Mg and P contents. Ca content was 601.78 kg/hm2 in the low density stand and 1 204. 43 kg/hm2 in the high density stand. 展开更多
关键词 Eucalyptus grandis Stand density Nutrient elements DISTRIBUTION
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Distribution and Accumulation of Nutrient Elements in Organic Tissue of Eucalyptus grandis Saplings 被引量:1
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作者 闵安民 王宇 +2 位作者 李红霞 费楠 李凤鸣 《Agricultural Science & Technology》 CAS 2015年第12期2749-2753,2880,共6页
The biomass, macroelements (N, P, K, Ca, Mg) and microelements (Fe, Zn) contents were detected in organs of 1a-3a Eucalyptus grandis saplings, as well as their accumulated amount. Results showed that contents of n... The biomass, macroelements (N, P, K, Ca, Mg) and microelements (Fe, Zn) contents were detected in organs of 1a-3a Eucalyptus grandis saplings, as well as their accumulated amount. Results showed that contents of nutrient elements varied greatly in different organs. Total contents of macroelements N, P, K, Ca and Mg in1a-3a E. grandis were distributed in the order of stem phloem, leaves 〉 branch- es, roots 〉 stem xylem. Accumulated amount of macroelements in 1a-3a E. grandis were in the order of leaves 〉 branches 〉 stem phloem 〉 roots or stem xylem 〉 stem xylem or roots. Accumulated amount law of nutrient elements was not affected by the plant age. Microelements Fe and Zn were mainly concentrated in the leaves and roots. The accumulation of macroelements was in the order of Ca 〉 N 〉 K 〉 Mg 〉 P; and the microelements was in the order of Fe 〉 Zn. Accumulated amounts of microelements in 1a-3a E. grandis were 12.45 136.19 and 420.23 g per plants, respectively. Among the annual net accumulated amount of nutrient ele- ments per plant in 1a-3a E. grandis, Ca element was the maximum, N and K ele- ments took the second and third places. Mg element was relatively small and P el- ement was the minimum. 展开更多
关键词 Eucalyptus grandis ORGAN Nutrient element Accumulated amount
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Leaf Area Calculation Model of E.urophylla and E.grandis×E.urophylla 被引量:1
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作者 朱宏光 赵金龙 +1 位作者 温远光 侯日华 《Agricultural Science & Technology》 CAS 2010年第8期4-6,9,共4页
[Objective] The aim was to build an optimal leaf area measurement model of E. urophylla and E. grandis×E.urophylla. [Method] The correlation between leaf area and leaf's eigenvalue of E. urophylla and E. grandis... [Objective] The aim was to build an optimal leaf area measurement model of E. urophylla and E. grandis×E.urophylla. [Method] The correlation between leaf area and leaf's eigenvalue of E. urophylla and E. grandis×E.urophylla were studied. [Result] There was certain difference in leaf characteristics values between the 2 species. The leaf areas of E. urophylla and E. grandis×E.urophylla both had significant correlation with leaf length,leaf width,leaf perimeter,leaf length × leaf width,the ratio of leaf length to leaf width,shape factor,etc.,so the factors could be constructed into a regression model with leaf area. Among them,the best 2 models for leaf area calculation which were built by leaf length × leaf width of E. urophylla and E. grandis×E.urophylla both had relatively high accuracy and practical applications. [Conclusion] The research provides a simple and effective leaf area measurement method for studies on the 2 tree species. 展开更多
关键词 E. urophylla E. grandis×E.urophylla Leaf's eigenvalue Leaf area Calculation model
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柚(Citrus grandis Osbeck cv.)MADS box基因的表达分析
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作者 张敬虎 潘一山 +5 位作者 王少峰 邹金美 陈羡德 林莹 王玉玲 蓝炎阳 《闽南师范大学学报(自然科学版)》 2015年第3期76-83,共8页
以De novo转录组学方法分析柚(Citrus grandis Osbeck cv.)MADS box基因家族的基因.以特早熟龙柚(变异型)和琯溪蜜柚(参照型)嫩果(不超过5天)和新叶为材料,经过RNA提取、反转录、测序、组装得到Unigene序列.Unigene序列在Nr、Swiss-Prot... 以De novo转录组学方法分析柚(Citrus grandis Osbeck cv.)MADS box基因家族的基因.以特早熟龙柚(变异型)和琯溪蜜柚(参照型)嫩果(不超过5天)和新叶为材料,经过RNA提取、反转录、测序、组装得到Unigene序列.Unigene序列在Nr、Swiss-Prot、KEGG和COG四大数据库中进行比对,获得MADS box转录因子家族基因注释结果.采用数字基因表达标签(digital gene expression tag,DGE)技术,对样本中基因转录丰度以RPKM值表示,比较处理组和对照组的RPKM值,以倍性变化≥2确定差异表达基因(differentially expressed genes,DEGs).从特早熟龙柚和琯溪蜜柚嫩果和叶片中,总共注释到28个MADS box基因家族基因.在龙柚嫩果(FE)和蜜柚嫩果(FL)中表达的有25个,其中有6个属于差异表达基因.在龙柚叶片(LE)和蜜柚叶片(LL)中表达的有27个,其中有7个属于差异表达基因.注释到的28个MADS box基因家族基因在克莱门特柚(Citrus clementina)和中国甜橙(Citrus sinensis)报道过的分别有18个和20个,其中有5个基因既在中国甜橙和克莱门特柚都没有报道过,也没有发现在其它Citrus物种报道过. 展开更多
关键词 柚(Citrus grandis OSBECK cv.) MADS BOX基因 差异表达基因(DEGs)
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Grandis电控节气门系统的原理和检修
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作者 何金戈 《汽车电器》 2009年第3期32-36,共5页
详细介绍三菱Grandis线控电子节气门系统的组成、构造和工作原理,以及检修和自适应方法。并用维修实例加以说明。
关键词 grandis 电子节气门 工作原理 检修
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大竹蛏(Solen grandis)不同地理群体遗传多样性的AFLP分析 被引量:8
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作者 张滔 刘相全 +4 位作者 孙振兴 乔洪金 孙国华 刘丽娟 宋向军 《海洋与湖沼》 CAS CSCD 北大核心 2013年第2期525-530,共6页
应用AFLP分子标记技术对我国沿海大竹蛏(Solen grandis)群体的遗传多样性进行了分析,利用筛选出的7对AFLP引物,对丹东、烟台、莱州、日照和南通5个地理群体的141只大竹蛏个体进行了扩增,共得到了403个位点,片段大小在100—700bp之间。... 应用AFLP分子标记技术对我国沿海大竹蛏(Solen grandis)群体的遗传多样性进行了分析,利用筛选出的7对AFLP引物,对丹东、烟台、莱州、日照和南通5个地理群体的141只大竹蛏个体进行了扩增,共得到了403个位点,片段大小在100—700bp之间。其中丹东、烟台、莱州、南通4个群体的大竹蛏遗传多样性水平接近,日照群体的多态位点比例高于其它4个群体,结合Shannon’s信息指数(I)和Nei’s基因多样性指数(H)看,日照群体的遗传多样性水平最高,而南通群体的遗传多样性水平最低。AMOVA分析得到群体间遗传分化系数Φst=0.2250(P<0.001),群体间的变异百分率为22.5%,群体内为77.5%,说明群体的遗传变异主要来源于群体内个体间的遗传差异,但群体间也存在一定程度的基因渗透。 展开更多
关键词 大竹蛏 AFLP 遗传多样性
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大竹蛏(Solen grandis)cDNA文库中微卫星标记的筛选 被引量:5
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作者 乔洪金 刘相全 +3 位作者 孙国华 房景辉 韦秀梅 张滔 《海洋与湖沼》 CAS CSCD 北大核心 2012年第6期1128-1133,共6页
利用微卫星查找软件SSRIT对大竹蛏cDNA文库(2038条EST)中2—6个碱基重复单元组成的简单序列重复进行了筛选。最少重复次数设定为5次,共发现包含微卫星位点的EST96条,占整个EST数据库的4.71%;共发现微卫星位点103个,其中含双碱基重复序... 利用微卫星查找软件SSRIT对大竹蛏cDNA文库(2038条EST)中2—6个碱基重复单元组成的简单序列重复进行了筛选。最少重复次数设定为5次,共发现包含微卫星位点的EST96条,占整个EST数据库的4.71%;共发现微卫星位点103个,其中含双碱基重复序列77个,数量最多,占总数的74.76%;三、四碱基重复序列分别占微卫星序列总数的22.33%、2.91%,没有发现五或六碱基的重复。对含有SSR位点符合微卫星引物设计的EST序列,利用在线引物设计软件Primer3设计合成引物14对,以南通野生群体为模板PCR扩增和聚丙烯酰胺凝胶电泳发现,其中5对有多态性位点。在5个微卫星位点上,等位基因的数目从2—7个不等,观测杂合度和期望杂合度分别为0.067—1.000和0.066—0.775,香农指数在0.146—1.545之间。结果表明,所筛选的微卫星标记可用于遗传分析。 展开更多
关键词 大竹蛏 微卫星 表达序列标签 等位基因
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我国沿海大竹蛏(Solen grandis)野生群体及增殖放流群体遗传多样性的ISSR分析 被引量:6
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作者 曹奕 吴洪喜 +6 位作者 陈爱华 吴杨平 张雨 王超 张志伟 姚国兴 蔡永祥 《海洋与湖沼》 CAS CSCD 北大核心 2015年第6期1398-1404,共7页
近年来,大竹蛏野生资源因过度捕捞等原因急剧减少,主要通过人工增殖放流方式进行补充。对我国沿海大竹蛏群体进行遗传多样性研究,评判增殖放流活动对野生群体遗传结构的影响,能够了解大竹蛏当前的种质资源状况,为合理保护该资源提供科... 近年来,大竹蛏野生资源因过度捕捞等原因急剧减少,主要通过人工增殖放流方式进行补充。对我国沿海大竹蛏群体进行遗传多样性研究,评判增殖放流活动对野生群体遗传结构的影响,能够了解大竹蛏当前的种质资源状况,为合理保护该资源提供科学依据。采用ISSR分子标记技术,对广西北海(BH)、江苏启东(QD)、山东日照(RZ)、辽宁营口(YK)、河北秦皇岛(QH)5个野生大竹蛏群体及江苏蒋家沙增殖放流群体(JJ)共150个样品进行了研究。实验结果表明,我国沿海大竹蛏遗传多样性水平高,但各野生群体间已出现显著的遗传分化;江苏蒋家沙增殖放流群体较启东野生群体遗传多样性有所下降,但两群体间的遗传分化并不明显。所以在苗种培育过程中,应当保证亲本数量及品质,扩大亲本选择区域来提高遗传多样性水平,同时应加大本地原种保护力度来避免种质混杂。 展开更多
关键词 大竹蛏 ISSR 遗传多样性 遗传结构
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热带柚木(Tectona grandis L. f.)人工林中不同邻体干扰强度下林木CO2气体交换特征 被引量:5
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作者 陈德祥 班小泉 +4 位作者 李意德 肖文发 骆土寿 林明献 许涵 《生态学报》 CAS CSCD 北大核心 2008年第9期4059-4069,共11页
研究以海南岛尖峰岭21a生的珍贵树种柚木人工林为对象,以邻体干扰指数为干扰强度评价指标,用Li-6400(Li-cor,Inc.,USA)便携式光合作用测定系统研究了邻体干扰强度对柚木个体CO2气体交换的日动态和季节变化特性,光合-光响应特性及光合-CO... 研究以海南岛尖峰岭21a生的珍贵树种柚木人工林为对象,以邻体干扰指数为干扰强度评价指标,用Li-6400(Li-cor,Inc.,USA)便携式光合作用测定系统研究了邻体干扰强度对柚木个体CO2气体交换的日动态和季节变化特性,光合-光响应特性及光合-CO2响应特性的影响。结果表明:邻体干扰并未改变个体叶片光合作用日进程,但对日净光合速率(Pn)的影响差异较大,表现为弱、中、强和极强度干扰下日Pn时段均值比为2.5∶2.3∶1.7∶1.0,弱干扰下日最大净光合速率为极强干扰下的2.8倍;随着干扰强度的增加,柚木叶片的蒸腾速率、气孔导度等特征参数也出现不同程度的下降。邻体干扰对光合-光响应和光合-CO2响应特征参数的影响明显,弱干扰下柚木叶Asat、Qsat、αA、CE、Vcmax和Jmax分别是极强干扰下的2.7、1.3、1.4、2.7、1.9和2.8倍,Qcomp和Rd则受邻体干扰的影响不明显。干扰强度对光合光响应和光合CO2响应特征的影响随光环境和CO2浓度的改变而有所差异,光环境的改变对弱干扰下柚木个体的影响明显要强于强度以上干扰的个体,而CO2浓度的改变对弱干扰个体的影响则明显要弱于强度干扰以上个体的影响。因此,在林分结构相对单一、经营管理措施基本一致的人工林内,邻体干扰是个体竞争的主要影响因素之一,干扰强度的不同将影响种内个体光合碳同化能力出现差别,导致个体生长差异。可以基于邻体干扰指数评价柚木人工林内种内竞争程度的大小,并以此为依据合理调整柚木人工林的林分结构,达到对环境资源的最合理利用。 展开更多
关键词 邻体干扰 竞争 CO2气体交换 柚木 尖峰岭
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抗风桐(Pisonia grandis)的生态生物学特征 被引量:11
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作者 王馨慧 刘楠 +2 位作者 任海 徐贝贝 简曙光 《广西植物》 CSCD 北大核心 2017年第12期1489-1497,共9页
抗风桐(Pisonia grandis)为紫茉莉科常绿乔木,是西沙群岛自然植被中最常见的乔木树种,具有重要的生态、药用和观赏价值;其生长速度快,断枝可再殖,在防风、海岸固沙以及海岛植被恢复方面具有重要作用。该研究以西沙群岛永兴岛的野生抗风... 抗风桐(Pisonia grandis)为紫茉莉科常绿乔木,是西沙群岛自然植被中最常见的乔木树种,具有重要的生态、药用和观赏价值;其生长速度快,断枝可再殖,在防风、海岸固沙以及海岛植被恢复方面具有重要作用。该研究以西沙群岛永兴岛的野生抗风桐为研究对象,对其形态解剖特征、生理特征和营养成分进行了研究。结果表明:抗风桐属阳生性树种,具有叶片厚、比叶面积低、栅栏组织发达、海绵组织细胞间隙小等形态解剖特征,利于其对光能和水分的利用;其超氧化物歧化酶和过氧化氢酶活性高、脯氨酸含量较高,丙二醛含量较低,表明其具有较强的抗旱性。抗风桐生长的土壤养分含量低,但其叶片营养元素含量高,表明抗风桐对土壤养分的利用能力高,对土壤养分贫瘠胁迫具有较强的适应性。因此,抗风桐能适应强光、干旱和贫瘠等生长条件,可作为热带珊瑚岛植被恢复的重要树种。由于抗风桐生长速度快、适应环境能力强,因此在栽培过程中应适时浇水及补充生长所需的矿质元素,以维持植株生长所需要的水分和养分平衡。该研究结果为抗风桐的引种、栽培、保护及开发利用提供了科学依据。 展开更多
关键词 抗风桐 生态生物学特性 抗逆性 开发利用
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大竹蛏(Solen grandis)铁蛋白基因的克隆及其在转录水平上对微生物多糖的应答 被引量:4
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作者 杨顶珑 韦秀梅 +5 位作者 杨建敏 杨嘉龙 徐洁 王圣 刘相全 张艳敏 《海洋与湖沼》 CAS CSCD 北大核心 2013年第3期664-669,共6页
本研究克隆获得了一个大竹蛏(Solen grandis)铁蛋白(SgFer)基因的cDNA全长,其序列全长为848bp,5’和3’端的非编码区分别为111bp和212bp,开放阅读框525bp,推测编码174个氨基酸,预测分子量为20.2kDa,理论等电点为5.20。通过荧光定量PCR... 本研究克隆获得了一个大竹蛏(Solen grandis)铁蛋白(SgFer)基因的cDNA全长,其序列全长为848bp,5’和3’端的非编码区分别为111bp和212bp,开放阅读框525bp,推测编码174个氨基酸,预测分子量为20.2kDa,理论等电点为5.20。通过荧光定量PCR法研究了SgFer在健康大竹蛏组织中以及大竹蛏受到微生物多糖刺激后的表达规律,结果表明,SgFer在血细胞、鳃、外套膜、肌肉、性腺和肝胰腺等组织器官中均有表达,在肝胰腺中的表达量最高。SgFer在大竹蛏受到肽聚糖(PGN)和葡聚糖(glucan)刺激后,其mRNA的表达量显著上调,分别在刺激后6h和12h达到最高;而脂多糖(LPS)刺激不能诱导其mRNA表达量上调。SgFer可能参与大竹蛏对微生物多糖的清除反应。 展开更多
关键词 大竹蛏 铁蛋白 基因克隆 荧光定量PCR
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柚树(Citrus grandis)叶片光合作用对补增UV-B辐射的响应 被引量:4
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作者 孙谷畴 赵平 +1 位作者 曾小平 彭少麟 《广西植物》 CAS CSCD 北大核心 2001年第1期72-76,共5页
生长在人工光照 4 0 0μmol m- 2 s- 1 下的柚树幼树光合速率的最大值为 1 0 .2± 0 .5μmol m- 2 s- 1 ;而补增UV-B辐射 ( 3.8-4 .2μW cm- 2 ,2 4 5~ 2 97nm,4 5d)的叶片则为 6.4± 0 .8μmol m- 2 s- 1 ,较对照植株降低37.... 生长在人工光照 4 0 0μmol m- 2 s- 1 下的柚树幼树光合速率的最大值为 1 0 .2± 0 .5μmol m- 2 s- 1 ;而补增UV-B辐射 ( 3.8-4 .2μW cm- 2 ,2 4 5~ 2 97nm,4 5d)的叶片则为 6.4± 0 .8μmol m- 2 s- 1 ,较对照植株降低37.2 %。对照植物的表观量子产率 (固定 mol CO2 mol- 1量子 )为 0 .0 75± 0 .0 1 2 ,而经 UV-B辐射处理植株则为0 .0 4 1± 0 .0 0 8,明显较对照植株低。UV-B辐射处理使植株叶片的光呼吸和不包括光呼吸的 CO2 补偿点增高。对照植株叶片的最大值的 CO2 羧化速率 (μmol m- 2 s- 1 )为 57.1± 1 .5μmol m- 2 s- 1 ,较 UV-B辐射处理的高30 .9% ,而 UV-B辐射处理的植株的光合电子传递速率较对照低 30 %。同时 UV-B辐射植株叶片有较低的光能转化效率 ,其较对照低 39.1 % ,叶片亦含有较低的叶绿素含量。结果表明 ,UV-B辐射明显抑制叶片光合羧化速率和光合电子传递速率 ,UV-B辐射可能抑制包括 Rubisco羧化作用在内的多个光合生理过程 ,降低叶片光合速率。柚树叶片对 UV-B辐射敏感 ,选育抗 UV-B辐射的柚树品种势在必行。 展开更多
关键词 柚树 补增UV-B辐射 叶片光合参数 光合作用
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Antidiabetic,antihyperlipidemic and antioxidant potential of methanol extract of Tectona grandis flowers in streptozotocin induced diabetic rats 被引量:7
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作者 Subramaniani Ramachandran Aiyalu Rajasekaran KT Manisenthil Kumar 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2011年第8期624-631,共8页
Objective:To investigate antidiabetic,antihyperlipidemic and antioxidant activity of methanol extract of Tectona grandis(T.grandis) flowers(METGF) in streplozotocin(STZ) induced diabetic rats to supports its tradition... Objective:To investigate antidiabetic,antihyperlipidemic and antioxidant activity of methanol extract of Tectona grandis(T.grandis) flowers(METGF) in streplozotocin(STZ) induced diabetic rats to supports its traditional use.Methods:Acute toxicity study of METGF was carried out in rat to determine its dose for the antidiabetic study.Oral glucose tolerance test(OGTT) was performed to evaluate METGF effect on elevated blood glucose level.Diabetes was induced in rats by administration of STZ(60 mg/kg,ip.) and it was confirmed 72 h after induction.METGF was orally given to the diabetic rats up to 28 days and blood glucose level were estimated each week.On 28 day of the experiment,diabetic rats were sacrificed after the blood collection for the biochemical parameters analysis and liver,kidney was collected to determine antioxidants levels.Results: In acute toxicity,METGF did not show toxicity and death up to a dose 2 000 mg/kg in rats. Administration of METGF 100 and 200 mg/kg significantly(P【0.001) reduced blood glucose levels in OGTT and STZ-induced diabetic rats.Both doses of METGF treatment significantly(P【0.001, P【0.01 and P【0.05) increased body weight,serum insulin,haemoglobin(Hb) and total protein levels in diabetic rats.Also,MEGTF treatment reduced elevated glycosylated haemoglobin(HbA1c) and other biochemical parameters levels significantly(P【0.001) in diabetic rats.Altered lipid profiles and antioxidants levels were reversed to near normal in diabetic rats treated with METGF. Conclusions:These results concluded that METGF possesses antidiabetic,antihyperglycemic and antioxidant activity which supports its traditional use. 展开更多
关键词 Diabetes STREPTOZOTOCIN Tectona grandis LIPID profile ANTIOXIDANT
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红脂大小蠹Dendroctonus valens(Coleoptera,Scolytidae)和大唼蜡甲Rhizophagus grandis(Coleoptera,Rhizophagidae)的耐寒性(英文) 被引量:9
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作者 赵建兴 杨忠岐 Jean-Claude Gregoire 《环境昆虫学报》 CSCD 北大核心 2009年第1期20-28,共9页
红脂大小蠹Dendroctonus valensLe Conte(Red turpentine beetle,RTB)是近年来在中国爆发的入侵生物,在我国主要以老熟幼虫在油松伐桩和立木的根部越冬。室内测定昆虫的过冷却点(SCP)和短时间致死低温(LLT)是评价昆虫耐寒能力的重要方... 红脂大小蠹Dendroctonus valensLe Conte(Red turpentine beetle,RTB)是近年来在中国爆发的入侵生物,在我国主要以老熟幼虫在油松伐桩和立木的根部越冬。室内测定昆虫的过冷却点(SCP)和短时间致死低温(LLT)是评价昆虫耐寒能力的重要方法。实验结果显示,红脂大小蠹越冬幼虫的平均过冷却点为-11.98±2.55℃,是一种耐冰冻的昆虫。红脂大小蠹的过冷却点在不同地理分布区的种群间有明显差异,老熟幼虫的过冷却点明显低于低龄幼虫,在越冬前和越冬后的幼虫间没有明显差异。红脂大小蠹幼虫在冬季至少可以忍受-23.5℃的大气温度安全越冬。从2001年开始引入我国的云杉大小蠹的捕食者大唼蜡甲(Rhizophagus grandis Gyll.)幼虫的过冷却点为-18.05±2.76℃,低于红脂大小蠹所有虫态的过冷却点,说明比红脂大小蠹有更强的耐寒能力。 展开更多
关键词 红脂大小蠹 大唼蜡甲 过冷却点 天敌 生物防治
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