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The plant Asparagus racemosus is one of the most widely used sources of phytoestrogens because of its high content of the steroidal saponins, shatavarins I-IV, in roots. The dry root of A. racemosus, known as "Rak-Sam-Sip" in Thai, is one of the most popular herbal medicines, used as an anti-inflammatory, an aphrodisiac and a galactagogue. Recently, the interest in plant-derived estrogens has increased tremendously, making A. racemosus particularly important and a possible target for fraudulent labeling. However, the identification of A. racemosus is generally difficult due to its similar morphology to other Asparagus spp. Thus, accurate authentication of A. racemosus is essential. In this study, 1557-bp nucleotide sequences of the maturase K (matK) gene of eight Asparagus taxa were analyzed. A phylogenetic relationship based on the matK gene was also constructed. Ten polymorphic sites of nucleotide substitutions were found within the matK sequences. A. racemosus showed different nucleotide substitutions to the other species. A polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis of the matK gene was developed to discriminate A. racemosus from others. Only the 650-bp PCR product from A. racemosus could be digested with BssKI into two fragments of 397 and 253-bp while the products of other species remained undigested. Ten commercially crude drugs were analyzed and revealed that eight samples were derived from A. racemosus while two samples of that were not. Thus, the PCR-RFLP analysis of matK gene was shown to be an effective method for authentication of the medicinally phytoestrogenic species, A. racemosus. 相似文献
23.
芦笋十四点负泥虫发生规律与防治技术初探 总被引:2,自引:0,他引:2
zhang@sina.com 《中国农学通报》2006,22(3):338-338
100029 北京市北三环中路9号 北京市植物保护站 相似文献
24.
为探索芦笋种植对冷凉沙化区土壤的改良效果,在山西省朔州市右玉县,以未种植芦笋裸沙地为对照(CK),设置种植芦笋1、2、3和4年共4个处理,通过田间试验测定不同种植年限芦笋田土壤理化特性和芦笋生长发育情况。结果表明,与CK相比,随种植年限增加,土壤黏粒和粉砂粒含量递增,砂粒含量递减,土壤容重递减,土壤田间持水量递增;土壤pH和可溶性盐浓度(EC)递减;土壤有机质、全氮、有效磷和速效钾含量逐年递增。种植芦笋3年的土壤粒级、土壤容重、田间持水量、pH、EC值、土壤肥力发生显著变化;连续种植芦笋4年的土壤黏粒含量较CK增加到29.8%,粉砂粒含量增加到12.6%,砂粒含量降低到57.6%,田间土壤持水量显著提高,土壤容重显著降低,土壤由砂质壤土向砂质黏土转变;土壤pH降低0.75,EC值降低0.08mS/cm;土壤有机质含量增加28.89%,全氮、有效磷和速效钾含量分别增加95.12%、94.92%和45.40%;芦笋产量达6 037.5kg/hm 2。综合分析,连续种植芦笋4年可改善沙化土壤的物理结构,提高土壤养分,降低盐碱程度。芦笋是冷凉沙化区土壤改良的先锋作物之一,可实现生态效益与经济效益并举。 相似文献
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本试验对芦笋组织培养中影响生根的培养基激素配比、嫩茎增殖培养中激素配比及嫩茎增殖次数等因素进行了研究。结果表明,嫩茎增殖培养基激素配比和嫩茎增殖次数等因素对后续的茎段生根有重要影响。芦笋组培再生完整植株优化培养过程为:芦笋外植体(茎段)在J2(MS NAA 0.2 mg/L BA 0.5 mg/L)培养中诱导出嫩茎后,再在嫩茎增殖培养基J3(MS NAA 0.2 mg/L BA 0.1 mg/L)或J9(MS NAA 0.05 mg/L BA 0.1 mg/L)增殖1次(嫩茎增殖次数对后续生根影响极大),然后取增殖1次后的茎段接种到生根培养基G4(MS IBA 0.5 mg/L BA 0.05 mg/L 2.0 mg/L PP333)中进行生根培养,最高生根率可达90%以上。芦笋组培苗移栽成活率主要受诱导出的根质量的影响。通过几个因素的优化,最终可使芦笋根诱导率达90%~100%,移植成活率达100%。 相似文献
27.
Summary The potential of isozymes for distinguishing asparagus varieties was carried out by a survey on 21 varieties using 10 enzyme systems: GOT, SkDH, DIA, PGM, MDH, IDH, PGD, ACP, PGI, MR and ADH. Only 3 enzymes, SkDH, GOT and PGM, showed useful polymorphisms. The varieties were found heterogeneous according to their genetic structure: open pollinated varieties were more heterogeneous than clonal hybrids; the F1 hybrid and the vitroclones were homogeneous. As expected from the narrow genetic basis of the varieties, only a few alleles per isozyme locus were present. Moreover, for each enzyme, one allele or type was predominant so that the discriminating power of the method was low. However some of the varieties could be identified and different applications of the results are presented.Abbreviations D.U.S.-
Distinction-Uniformity-Stability
- ACO-
aconitase
- ACP-
acid phosphatase
- ADH-
alcohol dehydrogenase
- CAT-
catalase
- DIA-
diaphorase
- END-
endopeptidase
- GOT-
glutamate oxaloacetate transaminase
- IDH-
isocitrate dehydrogenase
- MDH-
malate dehydrogenase
- MR-
menadione reductase
- PGI-
phosphoglucoisomerase
- PGM-
phosphoglucomutase
- PGD-
phosphoglucose dehydrogenase
- POX-
peroxidase
- SkDH-
shikimate dehydrogenase 相似文献
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石刁柏性别表现与同工酶的关系 总被引:6,自引:0,他引:6
采用聚丙烯酰胺凝胶电泳对石刁柏(AsparagusofficinalisL.)雌雄植株不同器官及不同组织的过氧化物酶同工酶谱进行了研究,结果表明,除根部外,尽管鳞片、茎尖、拟叶等器官酶谱有明显差异,但雌雄株间差异有相同的趋势。雄株均比相应的雌株少一条酶带,雌雄植株组织培养获得的愈伤组织和茎尖过氧化物酶同工酶酶谱差异也有类似的规律。说明石刁柏性别差异与过氧化物酶同工酶的数目有关,过氧化物酶同工酶谱的差异可以作为性别鉴定的指标。 相似文献
30.