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Effects of Weak Light on the Ultrastructural Variations of Phloem Tissues in Source Leaves of Three-Year-Old Nectarine Trees(Prunus persica L.var. nectarina Ait.) 被引量:6
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作者 王秀芹 黄卫东 《Acta Botanica Sinica》 CSCD 2003年第6期688-697,共10页
Leaves from three_year_old solar greenhouse nectarine trees ( Prunus persica L. var. nectarina Ait. “Zao Hong Yan”) were used as materials in this study. It was the first time that the ultrastructural charact... Leaves from three_year_old solar greenhouse nectarine trees ( Prunus persica L. var. nectarina Ait. “Zao Hong Yan”) were used as materials in this study. It was the first time that the ultrastructural characteristics of phloem tissues of source leaves were observed and compared in normal and weak light intensities using the transmission electron microscopy. Results showed that the average diameters of companion cells (CC) and sieve elements (SE) of all kinds of veins were bigger in normal than that in weak light intensity, indicating that light could influence the cell development and growth. Dense cytoplasm with abundant mitochondria, endoplasmic reticulums, multivesicular bodies, vesicles and plastids were observed in normal light intensity. On the contrary, CC with small vacuolar structures and few mitochondrias, endoplasmic reticulums were shown in weak light. Misalignment of grana thylakoid margins of nectarine leaves also was seen in weak light. The sieve pores of SEs were obstructed in weak light. Chloroplasts with numerous starch grains and few mitochondrias were noticed in the mesophyll cell (MES) surrounding the bundle sheath in weak light. The storage of starch grains appeared to result from an unbalance between photosynthate production and export of photosynthates. This observation provided a strong support to the point that most leaves export the most of assimilates in the light time. Plasmodesmal densities between SE/CC, CC/PP (phloem parenchyma cell), PP/PP and PP/BSC (bundle_sheath cell) decreased in weak light. Plasmodesmata were observed between CC/SE (NS) (nacreous_walled sieve element), PP/BSC in branch veins in normal light intensity, but not in weak light. Thus apoplasmic pathway may be the main mode of transport of assimilates in weak light, however symplasmic pathway may be the main mode of transport of assimilates in normal light intensity. These results demonstrated that the solar greenhouse nectarine trees could be adapted to the weak light via the ultrastructure variation of phloem tissues of the source leaves. 展开更多
关键词 nectarine (Prunus persica l.var. nectarina Ait.) phloem tissue ultrastructure weak light SE/CC complex phloem loading
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Effect of Combined Use of Boron and Manganese Fertilizers on the Nutritional Quality and Physiological Indices of Brassica campestris L.ssp.chinensis L.var.utilis
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作者 肖伟 刘红利 +1 位作者 梁英 黄长干 《Agricultural Science & Technology》 CAS 2013年第11期1591-1593,1598,共4页
[Objective] The purpose of this study is to determine the effects of com-bined use of boron and manganese fertilizers on the nutritional quality and physio-logical indices of Brassica campestris. [Method] In the nutri... [Objective] The purpose of this study is to determine the effects of com-bined use of boron and manganese fertilizers on the nutritional quality and physio-logical indices of Brassica campestris. [Method] In the nutrient solutions for growing B. campestris by hydroponics, boric acid and manganese sulfate were added at 0.5, 2.5, and 7.5 mg/L respectively. Another treatment without boron and manganese was prepared as the control. Quality and physiological indices of B. campestris in the 10 treatments were measured. [Result] Boron and manganese shared obvious in-teraction in improving the quality and physiological indices of B. campestris. To cul-tivate B. campestris with high quality and strong resistance, the optimum concentra-tions of boron and manganese in the nutrient solution should be 2.5 mg/L boric acid and 2.5-7.5 mg/L manganese sulfate. [Conclusion] The findings wil provide refer-ence for studying effects of trace elements on nutrient composition of vegetables. 展开更多
关键词 Boron and manganese fertilizer Brassica campestris L. ssp. chinensis l.var. utilis Quality Physiological activity
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Isolation,purification,structural characteristic and antioxidative property of polysaccharides from A.cepa L.var.agrogatum Don 被引量:15
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作者 Hongcheng Liu Hongxiu Fan +4 位作者 Jing Zhang Shanshan Zhang Wenting Zhao Tingting Liu Dawei Wang 《Food Science and Human Wellness》 SCIE 2020年第1期71-79,共9页
Allium cepa L.var.agrogatum Don(ALAP)is commonly consumed in China as well as other regions and has various beneficial health effects.A novel acidic polysaccharide(named ALAP-21)was obtained from ALAP by ultrasonic an... Allium cepa L.var.agrogatum Don(ALAP)is commonly consumed in China as well as other regions and has various beneficial health effects.A novel acidic polysaccharide(named ALAP-21)was obtained from ALAP by ultrasonic and microwave-assisted extraction and purification using DEAE-52 anion exchange and Sephadex G-100 columns.The monosaccharide composition,structural and antioxidative properties of ALAP-21 were investigated by GC–MS chromatography,FT-IR and NMR spectroscopies and three antioxidative activity tests in vitro.The results showed that ALAP-21 was a heteropolysaccharide composed of glucose,galacturonic acid,mannose,galactose,arabinose,rhamnose,xylose,fructose and glucuronic acid with a relative molar ratio of 26.282:27.546:11.400:4.781:2.467:2.445:3.622:1.106:1.753,owning(1→4)-β-d-Glcp,(1→4)-β-d-GalAp6Me3OA,(1→4)-β-d-Galp6OMe,(1→2)-β-l-Rhap,(1→4)-β-d-Manp glycosidic linkages.(1→4)-β-d-Glcp and(1→4)-β-d-GalAp6Me3OA residues might be the main components of the sugar chain backbone of ALAP-21.Furthermore,ALAP-21 exhibited high potential for DPPH radicals(82.02%),hydroxyl radicals(53.33%)and superoxide anion radicals(50.28%).These results provide a reference for further research and rational development of ALAP polysaccharides. 展开更多
关键词 POLYSACCHARIDES Allium cepa l.var.agrogatum Don Structural characterization Antioxidative property
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Protection of Veratrum nigrum L.var.ussuriense Nakai alkaloids against ischemia-reperfusion injury of the rat liver 被引量:5
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作者 Zhen-Zhen Wang Wei-Jie Zhao +7 位作者 Xue-Song Zhang Xiao-Feng Tian Yu-Zhu Wang Feng Zhang Jin-Chan Yuan Guo-Zhu Han Ke-Xin Liu Ji-Hong Yao 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第4期564-571,共8页
AIM: TO investigate the protective effects and possible mechanisms of Veratrum nigrum L. var. ussuriense Nakai alkaloids (VnA) on hepatic ischemia/reperfusion (I/R) injury in rats. METHODS: Forty male Wistar rat... AIM: TO investigate the protective effects and possible mechanisms of Veratrum nigrum L. var. ussuriense Nakai alkaloids (VnA) on hepatic ischemia/reperfusion (I/R) injury in rats. METHODS: Forty male Wistar rats were randomly divided into four experimental groups (n = 10 in each): (A) Control group (the sham operation group); (8) I/R group (pretreated with normal saline); (C) Small-dose (10 μg/kg) VnA pretreatment group; (D) Large-dose (20 μg/kg) VnA pretreatment group. Hepatic ischemia/ reperfusion (Hepatic I/R) was induced by occlusion of the portal vein and the hepatic artery for 90 min, followed by reperfusion for 240 min. The pretreatment groups were administered with VnA intraperitoneally, 30 min before surgery, while the control group and I/R group were given equal volumes of normal saline. Superoxide dismutase (SOD) activity, myeloperoxidase (MPO) activity and nitric oxide (NO) content in the liver tissue at the end of reperfusion were determined and liver function was measured. The expression of intercellular adhesion molecule-1 (ICAM-1) and E-selectin (ES) were detected by immunohistochemical examinations and Western blot analyses. RESULTS: The results showed that hepatic I/R elicited a significant increase in the plasma levels of alanine aminotransferase (ALT: 74.53 ± 2.58 IU/L vs 1512.54 ± 200.76 IU/L, P 〈 0.01) and lactic dehydrogenase (LDH: 473.48 ± 52.17 IU/L vs 5821.53 ± 163.69 IU/L, P 〈 0.01), as well as the levels of MPO (1.97 ± 0.11 U/g vs 2.57 ± 0.13 U/g, P 〈 0.01) and NO (69.37 ± 1.52 μmol/g protein vs 78.39 ± 2.28 μmol/g protein, P 〈 0.01) in the liver tissue, all of which were reduced by pretreatment with VnA, respectively (ALT: 1512.54 ± 200.76 IU/L vs 977.93 ± 89.62 IU/L, 909.81 ± 132.76 IU/L, P 〈 0.01, P 〈 0.01; LDH: 5821.53 ± 163.69 IU/L vs 3015.44 ± 253.01 IU/L, 2448.75 ± 169.4 IU/L, P 〈 0.01, P 〈 0.01; MPO: 2.57 ± 0.13 U/g vs 2.13 ± 0.13 U/g, 2.07 ± 0.05 U/g, P 〈 0.01, P 〈 0.01; NO: 78.39 ± 2.28 μmol/g protein vs 71.11 ± 1.73 μmol/g protein, 68.58 ± 1.95 μmol/g protein, P 〈 0.05, P 〈 0.01). The activity of SOD (361.75 ± 16.22 U/rag protein vs 263.19 ± 12.10 U/rag protein, P 〈 0.01) in the liver tissue was decreased after I/R, which was enhanced by VnA pretreatment (263.19 ± 12.10 U/rag protein vs 299.40 ± 10.80 U/rag protein, 302.09 + 14.80 U/rag protein, P 〈 0.05, P 〈 0.05). Simultaneously, the histological evidence of liver hemorrhage, polymorphonuclear neutrophil infiltration and the overexpression of ICAM-1 and E-selectin in the liver tissue were observed, all of which were attenuated in the VnA pretreated groups. CONCLUSION: The results demonstrate that VnA pretreatment exerts significant protection against hepatic I/R injury in rats. The protective effects are possibly associated with enhancement of antioxidant capacity, reduction of inflammatory responses and suppressed expression of ICAM-1 and E-selectin. 展开更多
关键词 Veratrum nigrum l.var. ussuriense Nakaialkaloids Hepatic Ischemia/Reperfusion Injury Intracellular adhesion molecule-i E-SELECTIN
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中国水仙(Narcissus tazetta L.var.Chinesis Roem)开花生理研究——Ⅰ.中国水仙的生物学特性及花芽分化的规律
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作者 李文仪 孙景欣 傅家瑞 《中山大学学报(自然科学版)》 CAS 1985年第1期134-136,共3页
中国水仙是多花水仙,具有较高的观赏价值,是我国传统出口珍贵花卉,在我国主要分布于漳州、崇明等地区.近年来,广东潮汕、广州郊区等地引种漳州水仙时均出现不同程度的退化现象,表现为鳞茎小、重量轻、花序数和总小花数均明显减少.针对... 中国水仙是多花水仙,具有较高的观赏价值,是我国传统出口珍贵花卉,在我国主要分布于漳州、崇明等地区.近年来,广东潮汕、广州郊区等地引种漳州水仙时均出现不同程度的退化现象,表现为鳞茎小、重量轻、花序数和总小花数均明显减少.针对这种情况,我们从1982年以来对中国水仙的生物学特性、生长发育。 展开更多
关键词 中国水仙 鳞茎 广州 小花 地下茎 广东 Narcissus tazetta l.var.Chinesis Roem 花芽分化 生物学特性
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Bio-productivity of Pinus sylvestris L.var. mongolica plantation on west Kerqin sandy land
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作者 郑景明 任恒德 孟康敏 《Journal of Forestry Research》 SCIE CAS CSCD 1998年第4期245-248,共4页
The biomass and net primary production of Mongolian scotch pine (Pinus sylvestris L. var mongolica) plantations of west Kerqin sandy land were measured. According to average standard trees, the biomass, netprimary pro... The biomass and net primary production of Mongolian scotch pine (Pinus sylvestris L. var mongolica) plantations of west Kerqin sandy land were measured. According to average standard trees, the biomass, netprimary production and their distributions of trunk, bark, branch, leaf and root of 16-year-old stand were analyzed.The regressive equation for the estimation of each organ biomass was established through djmensional analysis.Preferable equation with higher precision was selected. The study results showed that the total biomass of theforest community was 62.023 t/hm2 and net primary production was 5.045 V(hm2. a). which indicates that thecommunity of plantation possesses high bio-productivity. 展开更多
关键词 PINUS SYLVESTRIS l.var. MONGOLICA Biomass Net primary production Kerqin SANDY land
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Effects of Chlorine Dioxide Gas on Postharvest Physiology and Storage Quality of Green Bell Pepper (Capsicum frutescens L.var.Longrum) 被引量:37
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作者 DU Jin-hua FU Mao-run LI Miao-miao XIA Wei 《Agricultural Sciences in China》 CAS CSCD 2007年第2期214-219,共6页
The effects of treatment of chlorine dioxide (C1Oz) gas on postharvest physiology and preservation quality of green bell peppers were studied. Green bell peppers were collected in bags and treated with 0, 5, 10, 20,... The effects of treatment of chlorine dioxide (C1Oz) gas on postharvest physiology and preservation quality of green bell peppers were studied. Green bell peppers were collected in bags and treated with 0, 5, 10, 20, and 50 mg L^-1 ClO2 gas at 10±0.5℃ for over 40 d, and the changes in postharvest physiology and preservation quality of the peppers were evaluated during the storage. The inhibition of rot of the peppers was observed for all the tested ClO2 gas treatments. The rot rates of the treated samples were 50% lesser than those of the control after day 40 of storage. The highest inhibitory effect was obtained after 50 mg L^-1 ClO2 gas treatment, where the peppers did not decay until day 30 and showed only one-fourth of the rot rate of the control at day 40 of storage. The respiratory activity of the peppers was significantly (P〈0.05) inhibited by 20 and 50 mg L^-1 ClO2 treatments, whereas no significant effects on respiratory activity were observed with 5 and 10 mg L^-1 ClO2 treatments (P〉0.05). Except for 50 mg L^-1 ClO2, malondialdenyde (MDA) contents in the peppers treated with 5, 10, or 20 mg L^-1 ClO2 were not significantly (P〉0.05) different from those in the control. Degradation of chlorophyll in the peppers was delayed by 5 mg L-1ClO2, but promoted by 10, 20, or 50 mg L^-1 ClO2. The vitamin C content, titratable acidity, and total soluble solids of the peppers treated by all the tested ClO2 gas did not significantly change during the storage. The results suggested that ClO2 gas treatment effectively delayed the postharvest physiological transformation of green peppers, inhibited decay and respiration, maintained some nutritional and sensory quality, and retarded MDA accumulation. 展开更多
关键词 green bell pepper (Capsicum frutescens L. var. Longrum) chlorine dioxide gas post-harvest physiology storage quality
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Transformation of insect-resistant gene into cauliflower (Brassica oleracea L.var. botrytis)
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作者 吕玲玲 雷建军 +2 位作者 宋明 李立云 曹必好 《Agricultural Science & Technology》 CAS 2004年第3期17-21,共5页
Cowpea Trypsin Inhibitor (CpTI) gene was transferred into the cotyle dons and hypocotyls of cauliflower by Agrobacterium-mediated transformation met hod. The best selective concentration of kanamycin (kan) was 15 mg L... Cowpea Trypsin Inhibitor (CpTI) gene was transferred into the cotyle dons and hypocotyls of cauliflower by Agrobacterium-mediated transformation met hod. The best selective concentration of kanamycin (kan) was 15 mg L-1. The con centration of carbencillin (carb) was 500 mg L-1. 14 transgenic cauliflower pla nts were obtained. The putative transformants were assayed by PCR and Southern b lotting analysis. The results indicated that CpTI gene was transferred into caul iflower successfully. 展开更多
关键词 cauliflower (Brassica oleracea L. var. botrytis) Agrobacterium-me diated genetic transformation CpTI gene transgenic plant
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Comparative Anticancer Mechanisms of Viscum album var.coloratum Water Extract and Its Lectin on Primary and Metastatic Melanoma Cells
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作者 Chang-Eui Hong Su-Yun Lyu 《BIOCELL》 2025年第2期289-314,共26页
Objectives:Among cutaneous malignancies,melanoma stands out for its particularly aggressive nature,with therapeutic interventions becoming notably limited once the disease progresses.In this research,we investigate th... Objectives:Among cutaneous malignancies,melanoma stands out for its particularly aggressive nature,with therapeutic interventions becoming notably limited once the disease progresses.In this research,we investigate the tumor-suppressing capabilities of water-extracted Korean mistletoe(Viscum album var.coloratum)and its purified lectin component(V.album var.coloratum agglutinin,VCA)using two distinct mouse melanoma models:B16BL6 and B16F10 cell lines.Methods:The impact of water extract and VCA treatments on melanoma cells was assessed through multiple experimental approaches,examining cellular survival rates,programmed cell death pathways,multicaspase activity,and cell cycle distribution patterns.To elucidate the interconnections among various cellular responses,we employed a suite of statistical techniques encompassing correlation studies,principal component analysis(PCA)-based dimensionality reduction,and dendrogram-based clusteringmethodologies.Results:Thewater extract exhibited dosedependent cytotoxicity with IC50 values of 372.3±8.7μg/mL and 202.5±8.4μg/mL for B16BL6 and B16F10 cells,respectively.VCA showed more significant effects,with IC50 values of 0.1992±0.0041 and 0.1981±0.0098μg/mL for B16BL6 and B16F10 cells,respectively.Both agents induced substantial apoptosis with a significant progression from early to late apoptotic stages,reaching up to 59.4%total apoptotic cells for VCA treatment.This was confirmed by strong multicaspase activation,particularly in VCA-treated cells(up to 88.4%caspase-positive cells).The water extract showed modest effects on cell cycle distribution,with increases in G0/G1 phase(74.6%)in B16BL6 cells and S phase(19.2%)in B16F10 cells,while VCA treatment resulted in G2/M phase reduction(10.0%)in B16F10 cells.Correlation analysis revealed strong negative associations between cell viability and caspase activity(r=−0.843 to−0.878),while hierarchical clustering demonstrated distinct response patterns between low and high concentrations of both agents.Effect size analysis confirmed strong treatment impacts on cell viability(d=−5.89 to−6.12)and caspase activation(d=3.45 to 5.23).Conclusion:These findings suggest that Korean mistletoe water extract and its isolated lectin may affect both primary and metastatic melanoma cells through distinct mechanisms,demonstrating particular potency in caspase-dependent apoptosis induction.Our findings establish a robust foundation for developing novel therapeutic interventions derived from natural compounds to combat malignant melanoma with high metastatic potential. 展开更多
关键词 MISTLETOE MELANOMA apoptosis cell cycle caspase Viscum album l.var.coloratum
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羟丙基-β-环糊精包合宽叶缬草挥发油的工艺研究 被引量:1
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作者 郭玉虎 王平 +2 位作者 刘军锋 王旭 昝俊峰 《中南药学》 2025年第3期644-649,共6页
目的优化宽叶缬草挥发油环糊精包合工艺,提高宽叶缬草挥发油水溶性。方法采用相溶解度法探究不同环糊精对宽叶缬草挥发油的增溶作用,优选最佳包合材料;以包合材料与挥发油比例、包合时间、包合温度为影响因素,包合率、收率、含油率为综... 目的优化宽叶缬草挥发油环糊精包合工艺,提高宽叶缬草挥发油水溶性。方法采用相溶解度法探究不同环糊精对宽叶缬草挥发油的增溶作用,优选最佳包合材料;以包合材料与挥发油比例、包合时间、包合温度为影响因素,包合率、收率、含油率为综合评价指标,正交试验法优化缬草挥发油羟丙基-β-环糊精(HP-β-CD)包合工艺;傅里叶红外光谱(FTIR)、差示扫描量热法(DSC)、X射线衍射法(XRD)对包合物结构进行表征;顶空-气相色谱质谱联用法(HS-GC-MS)检测包合物中挥发性成分。结果最佳包合材料为HP-β-CD,最佳工艺为HP-β-CD与挥发油比例14∶1、包合时间90 min、包合温度50℃,包合物中主要成分为乙酸龙脑酯。结论宽叶缬草挥发油HP-β-CD包合工艺稳定、热稳定性强、增溶效果良好,能对活性成分乙酸龙脑酯进行选择性包合。 展开更多
关键词 宽叶缬草 挥发油 环糊精 乙酸龙脑酯 顶空-气相色谱质谱联用法
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Extraction,Purification,and Anti-Inflammatory Activity of Steroid Fraction from Physalis Alkekengi L.Var.Franchetii(Mast.)Makino 被引量:2
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作者 Tian-Yi Xia Yi Wang +12 位作者 Yan-Ni Yang Wu-Jing Wang Zi-He Ding Ren-Xing Zhong Ying Chen Wei Li Ming-Ming Peng Chuan-Qiu Li Li-Feng Shang Bing Liu Zhen-Yue Wang Chong-Rong Shi Zun-Peng Shu 《World Journal of Traditional Chinese Medicine》 CAS CSCD 2023年第2期167-177,共11页
Objective: As a traditional medicinal plant listed in the Chinese Pharmacopeia, Physalis alkekengi L. var. franchetii(Mast.) Makino(PAF) has a long medicinal history and high economic value. PAF has immunomodulatory p... Objective: As a traditional medicinal plant listed in the Chinese Pharmacopeia, Physalis alkekengi L. var. franchetii(Mast.) Makino(PAF) has a long medicinal history and high economic value. PAF has immunomodulatory properties and can be used to treat acute lung injury and eczema.The aim of this study is to solve the problems of extraction and purification of active components from PAF. Materials and Methods: The solvent to be used for extraction and its concentration, the solid-to-liquid ratio, and extraction duration were investigated using a single-factor experiment.An orthogonal design(L_(9)[3^(4)]) was used to determine the optimum extraction conditions. After optimization, the sample’s concentrations and flow velocity, the eluents and their velocity, adsorption time, and the removed water volume were measured. The content of the five steroids in the sample was determined by high-performance liquid chromatography(HPLC). We also investigated the anti-inflammatory property of PAF calyxes before and after purification. Results: The optimum extraction and purification processes were determined by single-factor analysis.AB-8 was identified as the best macroporous adsorption resin for enrichment. After optimization, the average total steroid content was 71.83%,and the average recovery was 90% after purification. Among the five steroid components detected by HPLC, physalin F showed the highest content. Furthermore, the sample obtained after purification could significantly inhibit paw edema by egg whites induced. Conclusions: An environmentally-sustainable, efficient, and stable process was first optimized for enriching and purifying total steroids from PAF. The process has the potential for further development and utilization in the pharmaceutical industry. 展开更多
关键词 Anti-inflammatory activity extraction and optimization process physalins Physalis alkekengi l.var.francheti(Mast.)Makino STEROIDS
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榆林市樟子松人工林土壤养分特征 被引量:1
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作者 白晓霞 崔洁 +1 位作者 周千强 齐凯乐 《湖北农业科学》 2024年第1期47-51,共5页
为进一步探明陕西省榆林市樟子松人工林的土壤养分变化特征,以5年生樟子松(Pinus sylvestris L. var. mongolica Litv.)纯林和5年生樟子松-胡枝子(Lespedeza bicolor Turcz.)混交林为研究对象,分析土壤有机质、硝态氮、有效磷、速效钾... 为进一步探明陕西省榆林市樟子松人工林的土壤养分变化特征,以5年生樟子松(Pinus sylvestris L. var. mongolica Litv.)纯林和5年生樟子松-胡枝子(Lespedeza bicolor Turcz.)混交林为研究对象,分析土壤有机质、硝态氮、有效磷、速效钾等理化指标以及土壤酶活性的变化特征。结果表明,樟子松纯林和樟子松-胡枝子混交林土壤有机质、有效磷和速效钾含量整体上均随着土层深度的增加呈下降趋势,全磷含量均随着土层深度的增加呈先升高后降低的趋势,硝态氮含量则均随着土壤深度的增加而增加,5个指标均表现为樟子松-胡枝子混交林高于樟子松纯林,且樟子松-胡枝子混交林各层土壤有效磷含量均显著高于樟子松纯林(P<0.05);樟子松纯林和樟子松-胡枝子混交林土壤含水率各土层间差异均不显著,樟子松-胡枝子混交林5~15 cm土层土壤含水率含量显著高于樟子松纯林(P<0.05);樟子松纯林和樟子松-胡枝子混交林土壤碱性磷酸酶活性、过氧化氢酶活性、脲酶活性均随着土层深度的增加而降低,且樟子松-胡枝子混交林过氧化氢酶活性和脲酶活性在各土层均显著高于樟子松纯林(P<0.05)。 展开更多
关键词 樟子松(Pinus sylvestris l.var.mongolica Litv.) 纯林 混交林 土壤理化指标 酶活性 榆林市
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Two new taraxastane-type triterpenoids from the fruit of Cicuta virosa L.var latisecta Celak
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作者 Li, Zhen Lin Qian, Shi Hui Pu, She Ban 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第3期317-321,共5页
Two new taraxastane-type triterpenoids,20-taraxastene-3β,12β,16β-triol 1 and 3β-feruloyloxy-20-taraxastene-16β,28-diol 2, were isolated from the fruit of Cicuta virosa L.var latisecta Celak.There structures were ... Two new taraxastane-type triterpenoids,20-taraxastene-3β,12β,16β-triol 1 and 3β-feruloyloxy-20-taraxastene-16β,28-diol 2, were isolated from the fruit of Cicuta virosa L.var latisecta Celak.There structures were elucidated by ESI-MS,1D- and 2D-NMR spectroscopic methods. 展开更多
关键词 Cicuta virosa l.var latisecta Celak Cicuta TRITERPENE 20-Taraxastene-3β 12β 16β-triol 3β-Feruloyloxy-20-taraxastene-16β 28-diol
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新疆杨树干液流的径向变化及时滞特征 被引量:20
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作者 党宏忠 杨文斌 +2 位作者 李卫 刘世增 张友焱 《生态学报》 CAS CSCD 北大核心 2015年第15期5110-5120,共11页
利用热扩散技术,对绿洲农田防护林新疆杨(Populus alba L.var.pyramidalis)大树边材5个深度处(1、2、3、5 cm和8 cm)的液流速率(Js)开展了连续两年的监测,结果表明:(1)以标准长度2 cm的探针测得的液流速率(Js-2)为参照,形成层下1、3、5... 利用热扩散技术,对绿洲农田防护林新疆杨(Populus alba L.var.pyramidalis)大树边材5个深度处(1、2、3、5 cm和8 cm)的液流速率(Js)开展了连续两年的监测,结果表明:(1)以标准长度2 cm的探针测得的液流速率(Js-2)为参照,形成层下1、3、5、8 cm处的液流速率(Js-1,Js-3,Js-5,Js-8)与Js-2间具有显著的相关性,回归系数分别为0.24—0.27、1.18—1.61、0.81—1.64和0.38—0.75,液流速率最大的位点在形成层下3—5 cm处,液流速率最小的位点在最外侧(1 cm)或最内侧(8 cm)处,径向差异明显。边材不同深处的液流传输具有较一致的日变化过程。(2)在同步观测的5项气象要素中,大气水汽压亏缺(VPD)和太阳辐射(Ra)与Js的回归系数均较大,是驱动液流进程的主导气象要素。大气蒸发潜力(ET0)集合了多种气象要素的信息,具有与Ra一致的日变化进程(启动、峰值时刻相同),可作为分析液流昼、夜过程的综合气象变量。(3)新疆杨边材中五个深度处Js的峰值时刻基本相同(Js-1的峰值较其它层次提前4—123 min),均明显滞后于Ra(时滞)并提前于VPD,在7月份的晴天,ET0、Js和VPD峰值出现的时刻分别大致在12:30、14:00和15:00。新疆杨时滞的大小存在有规律的季节变化,从6到10月份,Js与ET0峰值的时滞(ΔJ-E)逐渐增加,变化在70—110 min(2011)、70—128 min(2012)之间,但VPD与Js峰值的时滞(ΔJ-V)逐渐降低,变化在73—20 min(2011)、63—8 min(2012)之间,这表明在生长季的早期,热量因子(Ra)对新疆杨液流变化的驱动较强,而在生长季的末期,大气水汽因子VPD的驱动效应更突出。 展开更多
关键词 新疆杨(Populus ALBA l.var.pyramidalis) 绿洲 树干液流 时滞
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结球甘蓝不同初级三体n+1配子的形成及传递率研究 被引量:5
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作者 张成合 祝海燕 +3 位作者 王梅 申书兴 王新娥 黄亚群 《中国农业科学》 CAS CSCD 北大核心 2008年第3期766-771,共6页
【目的】n+1配子传递率是进行三体遗传分析的重要参数。测定结球甘蓝"初级三体系"不同三体的n+1配子传递率为利用该"初级三体系"进行基因定位等遗传研究创造条件。【方法】结球甘蓝各初级三体分别与其二倍体亲本-9... 【目的】n+1配子传递率是进行三体遗传分析的重要参数。测定结球甘蓝"初级三体系"不同三体的n+1配子传递率为利用该"初级三体系"进行基因定位等遗传研究创造条件。【方法】结球甘蓝各初级三体分别与其二倍体亲本-9601进行相互杂交,杂交种子接种到MS培养基上培养繁殖成单株无性系;根尖染色体计数法鉴定杂交子代植株的染色体数目,用鉴定出的三体(2n+1=19)株数占鉴定植株总数的百分比表示n+1配子的传递率。【结果】各初级三体的n+1雌配子的传递率分别为15.28%(Tri-1)、12.68%(Tri-2)、12.31%(Tri-3)、30.51%(Tri-4)、22.81%(Tri-5)、7.46%(Tri-6)、5.36%(Tri-7)、42.37%(Tri-8)、9.23%(Tri-9);n+1雄配子的传递率分别为12.12%(Tri-1)、12.33%(Tri-2)、7.81%(Tri-3)、4.76%(Tri-4)、8.93%(Tri-5)、10.94%(Tri-6)、1.54%(Tri-7)、2.94%(Tri-8)、13.04%(Tri-9)。影响n+1雄配子形成和传递的因素主要有减数分裂前期Ⅰ三价体形成的频率、后期Ⅱ9/9/10/10分离的频率和花粉的生活力等。【结论】结球甘蓝各初级三体的额外染色体通过雌、雄配子均能传递给子代。 展开更多
关键词 结球甘蓝(B.oleracea l.var. capitata L.) 初级三体 n+1配子 传递率
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我国单叶蔓荆药用植物资源调查 被引量:15
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作者 梁芳 周香珍 曹岚 《安徽农业科学》 CAS 北大核心 2011年第35期21638-21640,共3页
[目的]调查我国单叶蔓荆的资源状况,为单叶蔓荆的可持续利用提供科学基础和参考依据。[方法]采用走访调查和实地样方调查的方法分别对我国单叶蔓荆野生和栽培资源进行调查。[结果]与第3次中药资源普查相比,除江西省单叶蔓荆分布面积增加... [目的]调查我国单叶蔓荆的资源状况,为单叶蔓荆的可持续利用提供科学基础和参考依据。[方法]采用走访调查和实地样方调查的方法分别对我国单叶蔓荆野生和栽培资源进行调查。[结果]与第3次中药资源普查相比,除江西省单叶蔓荆分布面积增加外(增加15.5%),其余各省分布面积均明显减少。从目前资源拥有量状况来看,单叶蔓荆处于原始状态的为876.33 hm2,占总数的31.3%;处于被轻度采挖的为405.00 hm2,占总数的14.4%;处于被过度采挖的为625.33 hm2,占总数的22.3%;处于残存的为895.64hm2,占总数的32.0%。[结论]我国单叶蔓荆资源正在减少,人们对其资源保护的认识不够,需加强对其资源的保护力度。 展开更多
关键词 单叶蔓荆(Vitex trifolia l.var.simplicifolia Cham.) 资源调查 分布范围 分布面积 年蕴藏量
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鲜食糯玉米品比试验 被引量:5
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作者 张姿丽 冯发强 +4 位作者 张媛 蒋锋 刘鹏飞 陈青春 王晓明 《湖北农业科学》 北大核心 2012年第17期3689-3692,共4页
对20个鲜食糯玉米(Zea mays L.var.ceratina Kulesh)杂交组合进行品比试验鉴定,初步总结了各参试糯玉米杂交组合的鲜苞产量、田间植株性状、果穗性状及品质表现。结果表明,杂交组合wh1、wh8、wh12产量、品质均优于对照香白糯,推荐参加... 对20个鲜食糯玉米(Zea mays L.var.ceratina Kulesh)杂交组合进行品比试验鉴定,初步总结了各参试糯玉米杂交组合的鲜苞产量、田间植株性状、果穗性状及品质表现。结果表明,杂交组合wh1、wh8、wh12产量、品质均优于对照香白糯,推荐参加鲜食糯玉米的区试,进行审定。 展开更多
关键词 糯玉米(Zea mays l.var. ceratina Kulesh) 杂交组合 品比试验
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不同土壤类型对红菜薹品质的影响 被引量:3
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作者 汪洋 胡先祥 +4 位作者 高立 冷艳芝 朱林耀 胡雷 钟文忠 《湖北农业科学》 北大核心 2014年第5期1099-1102,1105,共5页
为摸清历史上与洪山区同属武昌县的江夏区种植洪山菜薹的可行性,在位于江夏区法泗镇的公司甲、位于江夏区郑店街的公司乙、洪山菜薹原产地进行了不同土壤类型种植洪山菜薹品质对比试验。对6个不同土壤样品进行检测,在红菜薹(Brassica ca... 为摸清历史上与洪山区同属武昌县的江夏区种植洪山菜薹的可行性,在位于江夏区法泗镇的公司甲、位于江夏区郑店街的公司乙、洪山菜薹原产地进行了不同土壤类型种植洪山菜薹品质对比试验。对6个不同土壤样品进行检测,在红菜薹(Brassica campestris L.ssp Chinensis L.var.utilis Tsen et Lee)种质和栽培管理相同条件下,分别测定对应土壤的红菜薹主薹和侧薹品质。结果表明,原产地种植的洪山菜薹主薹品质最好,公司甲黄土种植的洪山菜薹侧薹品质最好;在品种、田间管理相同的条件下,土质是关键所在;在江夏区搞好洪山菜薹示范生产,延伸产业链是可行的。 展开更多
关键词 红菜薹(Brassica CAMPESTRIS L.ssp CHINENSIS l.var.utilis Tsen et Lee) 土壤类型 品质
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高山薇菜中多酚类化合物提取条件的优化 被引量:2
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作者 郭凤领 李俊丽 +2 位作者 王运强 吴金平 邱正明 《湖北农业科学》 北大核心 2014年第21期5224-5226,共3页
以粉碎的高山薇菜(Osmunda cinnamomea L.var.asiatica)粉末为原料,通过水煮法提取并测定薇菜中的多酚含量。单因素、正交优化试验结果表明,薇菜中多酚提取的最佳条件为温度90℃,提取时间6 h,料液比1∶30(g∶m L)。在此条件下,薇菜中的... 以粉碎的高山薇菜(Osmunda cinnamomea L.var.asiatica)粉末为原料,通过水煮法提取并测定薇菜中的多酚含量。单因素、正交优化试验结果表明,薇菜中多酚提取的最佳条件为温度90℃,提取时间6 h,料液比1∶30(g∶m L)。在此条件下,薇菜中的多酚含量可达3.413 mg/g。 展开更多
关键词 薇菜(Osmunda cinnamomea l.var.asiatica)粉 多酚 提取 优化
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小网格防护林影响土壤蒸发机理及节水、减盐效应 被引量:2
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作者 刘静 崔学明 +2 位作者 王林和 孙旭 郭永贞 《水土保持研究》 CSCD 北大核心 2006年第1期28-31,71,共5页
采用热平衡法研究新疆杨防护林林网内外的土壤蒸发量、蒸发效能及相关气象因子,用主成分分析探讨小网格防护林影响土壤蒸发的主要因子为空气温度因子、空气湿度因子、近地层风速因子和太阳辐射平衡值;分析新疆杨防护林对主导因子的影响... 采用热平衡法研究新疆杨防护林林网内外的土壤蒸发量、蒸发效能及相关气象因子,用主成分分析探讨小网格防护林影响土壤蒸发的主要因子为空气温度因子、空气湿度因子、近地层风速因子和太阳辐射平衡值;分析新疆杨防护林对主导因子的影响程度;推算林网内表层土壤减盐量。 展开更多
关键词 新疆杨(Populus ALBA l.var.pyramidalis) 小网格防护林 土壤蒸发
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