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61.
Ignacio E. Maldonado-Mendoza Terasa R. Del Ayora-Talavera Victor M. Loyola-Vargas 《In vitro cellular & developmental biology. Plant》1992,28(2):67-72
Summary Tropane alkaloid production was studied in different root cultures ofDatura stramonium. Cultured roots were obtained with 10−6
M of indolbutyric acid. Their doubling times were from 6 to 19 days. Hyoscyamine content varied from 0.17 to 0.62% dry weight,
and scopolamine content from 0.08 to 0.33% dry weight, depending on the lines. A comparison of the bioproductivity of these
compounds in the pot-grown plant roots showed that it was two to three orders lower than cultured roots, and it increased
one order of magnitude considering the productivity on the whole plant. Bioproductivity, growth capacity and alkaloid production
stability during subsequent transfers (more than 2 yr) are reported. Only one root line (N5) showed excretion of the alkaloids
to the culture medium. Characterization of three selected lines (N1, N5, and N9) showed that the highest alkaloid production
is reached at the stationary phase of growth, with the exception of line N9. 相似文献
62.
Summary Alkaloids washed from the seeds ofDatura stramonium inhibited the early gowth ofHelianthus annuus in Black Earth and Lateritic Podzolic soils. Under laboratory conditions, the magnitude of the inhibition was greater in the Lateritic Podzolic than the Black Earth soil. Phytotoxicity ofD. stramonium alkaloids persisted for 20 weeks in Lateritic Podzolic soil under controlled conditions, and for eight months in aD. stramonium-infested Black Earth soil in the field. 相似文献
63.
Putrescine N-methyltransferase (PMT) catalyses S-adenosylmethionine (SAM)-dependent methylation of putrescine in tropane alkaloid biosynthesis. PMT presumably evolved from the ubiquitous spermidine synthase (SPDS). SPDS protein structure suggested that only few amino acid exchanges in the active site were necessary to achieve PMT activity. Protein modelling, mutagenesis, and chimeric protein construction were applied to trace back evolution of PMT activity from SPDS. Ten amino acid exchanges in Datura stramonium SPDS dismissed the hypothesis of facile generation of PMT activity in existing SPDS proteins. Chimeric PMT and SPDS enzymes were active and indicated the necessity for a different putrescine binding site when PMT developed. 相似文献
64.
曼陀罗种子休眠机理与破眠方法研究 总被引:6,自引:0,他引:6
通过对曼陀罗种子生活力测定、发芽试验、吸水率测定及种子萌发抑制物研究,揭示曼陀罗种子休眠机理,并利用物理、化学法处理曼陀罗种子,以探寻打破曼陀罗种子休眠的最佳方法.结果表明:(1)新采收的曼陀罗种子为综合休眠,休眠原因包括:种皮障碍、缺少萌发所需激素以及种皮和种仁中存在萌发抑制物,其中种皮障碍是限制种子萌发的首要因素.(2)室温存储6个月可解除曼陀罗种子种仁的休眠,但种皮障碍始终是其种子萌发的限制因素.(3)机械摩擦、浓H2SO4处理和NaOH处理均可打破除曼陀罗种皮的休眠障碍,促进种子萌发,其中用10% NaOH处理90 min为破除曼陀罗种皮休眠障碍的最佳方法,且发芽率比对照提高了83%. 相似文献
65.
New necrotic isolates of Pepino mosaic virus (PepMV) were found in 2007 infecting greenhouse tomato plants in Poland. The isolates differ from previously identified PepMV isolates in host range and symptomatology. They induce severe necrosis on tomato plants ( Solanum lycopersicum ) and local necrotic lesions on Datura inoxia . Phylogenetic analysis, based on three distinct regions, triple gene block 1, the coat protein gene and a part of polymerase gene, revealed that the new necrotic isolates share high nucleotide sequence identity with isolates of the Ch2 genotype. This is the first report describing a necrotic type of PepMV of the Ch2 genotype. 相似文献
66.
曼陀罗种子油脂肪酸化学成分研究 总被引:1,自引:0,他引:1
以石油醚为溶剂提取曼陀罗种子中的脂肪酸,采用GC-MS技术测定其化学成分,并通过饲料混毒法测定了曼陀罗种子脂肪酸对小鼠的毒性.结果表明,曼陀罗种子中含有23.2%的脂肪酸,其主要化学成分为1,20-二十碳二酸(34.55%)、Crinan-3-ol,1,2-didehydro-,(3à)(13.41%)、8,11-十八碳二烯酸(4.56%)、8,11,14-二十碳三烯酸(Z,Z,Z)(4.39%)、2,3,3-三甲基辛烷(4.35%)、7,10-十八碳二烯酸(3.61%)、亚油酸乙脂(2.64%)、α-亚麻酸(2.34%)、cis-乙酸环己脂-2-丙酸(2.34%)等.采用饲料混毒法对小鼠的毒性测定结果表明,曼陀罗种子脂肪油对小鼠无胃毒作用.研究认为,曼陀罗种子中含有多种对人体有益的活性成分,可作为脂肪酸食用油来源或从中提取对人体有益的活性成分开发利用. 相似文献
67.
木本曼陀罗毛状根植株再生体系的建立 总被引:3,自引:0,他引:3
建立了木本曼陀罗(Datura arborea L.)毛状根的植株再生体系并对再生植株进行了初步检测.采用"一步法"诱导不定芽的适宜培养基为MS 6-BA 2.0 mg L-1 NAA 0.2 mg L-1;采用"两步法"诱导不定芽时,先在MS 6-BA 4.0 mg L-1 KT 0.5 mgL-1 2.4-D 0.5 mg L-1.上诱导愈伤组织,然后在MS 6-BA 4.0 mg L-1 NAA 0.2 mgL-1上诱导愈伤组织分化不定芽.诱导不定芽的最适宜生根培养基为1/2MS IBA 0.1 mgL-1.用PCR技术从再生植株叶片中得到了rolB、rolC目的基因片段.HPLC检测结果表明毛状根再生植株中莨菪烷类生物碱(Tropme alkaloids,TA)的含量较野生植株有明显的提高. 相似文献
68.
本文从植物曼陀(Datura arborea)中分离得到77株内生真菌。对它们分别进行菌株发酵,发酵产物经乙醇浸提,采用TLC和生物碱显色方法,观察到菌株Ym311977、Ym312023呈生物碱阳性反应。结合HPLC分析结果,表明该生物碱并非曼陀罗植物中的主要生物碱成份。经鉴定,Ym311977属镰孢菌属(Fusarium sp.),Ym312023属毛壳菌属(Chaetomium sp.)。 相似文献
69.
Genetic stability of hairy root cultures of Datura stramonium 总被引:2,自引:0,他引:2
Baíza Ana María Quiroz-Moreno Adriana Ruíz José Alfredo Loyola-Vargas Victor M. 《Plant Cell, Tissue and Organ Culture》1999,59(1):9-17
The karyotypic status of three root lines, transformed with Agrobacterium rhizogenes, versus a non-transformed root line of Datura stramonium, as well as grown plants (control), was investigated. In the transformed cultures, the karyotype as well as the number of
chromosomes (2n = 24) remained the same as in the control plants. In the normal root line there were clear differences at a morphological
level despite showing the same chromosomic number (2n = 24) at a high frequency. The existence of aneuploids (2n = 2n ± x) and tetraploids (2n = 4x = 48) was also observed in the latter. The frequency of chromosomic alterations was very low in all the cultures. Cytogenetic
analysis of the transformed root cultures of D. stramonium reported here shows a great chromosomic stability, which is not the case with normal root cultures.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
70.
Populations of Datura wrightii vary in the frequency of plants that produce glandular trichomes, a resistance trait under the control of a single gene.
Such variation may be maintained if the production of glandular trichomes is costly in the absence of herbivory, and if selection
imposed by herbivore communities varies spatially or temporally. Here, we document costs in the presence of herbivory for
established glandular plants relative to established non-glandular plants growing in natural populations from coastal mountain,
Riversidian sage scrub, and Mojave desert habitats in southern California. Damage caused by the herbivore community varied
spatially, with significant differences in herbivore-specific damage between plants of the two trichome types and among populations
within habitats, although not generally among habitats. Plants with greater canopy size and canopy persistence had higher
viable seed production than smaller or more damaged plants, but this relationship was statistically significant only for non-glandular
plants. However, the relationship between viable seed production and canopy persistence became significant for glandular plants
when damage caused by sap suckers, which do not remove leaf area, was pooled with undamaged leaf area. The high cost exhibited
by glandular plants leads us to predict that in the absence of any additional, unknown benefits of producing glandular trichomes,
the frequency of these plants should decline in all natural populations of D. wrightii.
Received: 13 July 1999 / Accepted: 28 September 1999 相似文献