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161.
UV-B辐射和干旱对丹参生长和叶片中酚酸类成分的影响 总被引:1,自引:0,他引:1
在3种UV-B辐射强度以及3种干旱的单因子以及复合作用下,采用盆栽法对丹参植株生物量、叶面积、株高等形态指标和光合参数以及叶片中丹酚酸B、迷迭香酸、咖啡酸和丹参素含量的变化进行研究。旨在探索西北干旱、半干旱地区强光和干旱对丹参生物量和叶片中酚酸类含量的影响,为丹参的深入开发利用提供依据。结果表明:干旱和UV-B辐射单因子作用均对丹参生长指标有抑制作用,而对酚酸积累有促进作用;相比于干旱,UV-B辐射的影响更加显著。UV-B辐射显著引起植株矮化、叶面积减小、生物量降低、净光合速率降低以及叶片中酚酸类物质含量增加,两种因子复合作用对酚酸类物质积累的效果表现为复杂的加强或交互抗性作用。两种因子单独和复合作用处理下,适宜水分和重度UV-B辐射复合处理(75%T2)最有利于丹参叶片中酚酸类物质积累。 相似文献
162.
The branching system of higher plants plays a very important role in plant morphogenesis, and the number of branches can directly affect crop yield and the ornamental value of plants. It is a complicated development process involving complex molecular mechanisms. The ‘Cailinghong’ variety of Salvia splendens is characterized by its great branching ability with the ability to grow into a spherical form naturally, without pinching. To gain insight into the molecular events during the branching development of S. splendens, suppressive subtractive hybridization (SSH) technology was used to screen differentially expressed genes between the erect plant type (strain 35) and the spherical plant type (‘Cailinghong’). In total, 96 and 116 unigenes were annotated. Four and eight unigenes up-regulated in ‘Cailinghong’ and strain 35, respectively, were associated with plant hormone anabolism and signal transduction, suggesting that they participate in the branching process. One of these genes, phytoene synthase (PSY), is a precursor of the new plant hormone group strigolactones. Using the PSY fragment (192 bp) as a template, the cDNA sequence of PSY in S. splendens was cloned and named SsPSY. A relative expression analysis and transgenic test results indicated that SsPSY plays an important role in lateral branch development in ‘Cailinghong’. These results provide new insight into the molecular mechanisms underlying branching in S. splendens. 相似文献
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Kawahara N Tamura T Inoue M Hosoe T Kawai K Sekita S Satake M Goda Y 《Phytochemistry》2004,65(18):2577-2581
The structure of four diterpenoid glucosides, designated as salvigresides A-D (1-4), isolated from the aerial parts of Salvia greggii, have been confirmed by spectroscopic and chemical investigation. 相似文献
165.
Promotion of phenolic compounds production in Salvia miltiorrhiza hairy roots by six strains of rhizosphere bacteria
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Salvia miltiorrhiza Bunge is an important herb for the treatment of cerebrovascular and cardiovascular diseases with bioactive compounds (phenolic acids and tanshinones). Abundant studies showed that tanshinones could be stimulated by biotic and abiotic stresses, but limited information is available on biosynthesis of phenolic acids promoted by biotic stresses. The aim of the present work was to isolate and identify rhizosphere bacteria which stimulated phenolic compound in Salvia miltiorrhiza hairy roots and investigated the internal mechanism, providing a potential means to enhance content of pharmaceuticals in S. miltiorrhiza. The results showed that six bacteria, namely, HYR1, HYR26, SCR22, 14DSR23, DS6, and LNHR13, belonging to the genus Pseudomonas and Pantoea, significantly promoted the growth and content of major phenolic acids, RA and SAB. Bacteria LNHR13 was the most effective one, with the contents of RA and SAB reaching ~2.5‐fold (30.1 mg/g DW) and ~2.3‐fold (48.3 mg/g DW) as those of the control, respectively. Phytohormones and polysaccharides produced by bacteria showed potential responsibility for the growth and biosynthesis of secondary metabolites of S. miltiorrhiza. Meanwhile, we found that the more abundant the types and contents of phytohormones, the stronger their stimulating effect on the content of salvianolic acids. 相似文献
166.
Regina Karousou Despina Vokou Stella Kokkini 《Biochemical Systematics and Ecology》1998,26(8):889-897
The distribution of Salvia pomifera subsp. pomifera (Cretan sage) on the island of Crete is presented. The essential oils of six populations scattered on the island are studied. The essential oil content varies from 2.1–4.2%, whereas the main oil components were in all cases α- and/or β-thujone (27.4–72.3% and 7.1–40.8%, respectively). The comparison of our results to literature data, suggest that S. pomifera can be distinguished from S. fruticosa (Greek sage), on the basis of its essential oil composition. 相似文献
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169.
John W. Dover 《Entomologia Experimentalis et Applicata》1986,42(3):243-247
Small-scale greenhouse intercrop experiments were carried out, with Brussels sprouts (Brassica oleracea gemmifera L.) as crop plants and the herbs sage (Salvia officinalis L.) and thyme (Thymus vulgaris L.) as intercrops. Significant reductions in diamond-back moth (Plutella xylostella (L.)) oviposition were observed on intercropped brassicas.Green polyethylene models were shown to simulate the effect of the herbs. Contrast was shown to have no effect on oviposition by the diamond-back moth.An intercrop of white clover (Trifolium repens L.) vs. an intercrop of thyme, resulted in significantly lower egg-loads on brassicas associated with clover. An olfactory effect is postulated to account for this difference.
Effets de la présence de Labiées et de treèfle blanc sur la ponte dePlutella xylotella
Résumé Le chou de Bruxelles (Brassica oleracea gemmifera L.), comme plante cultivée, et la sauge (Salvia officinalis L.) et le thym (Thymus vulgaris L.), ont été utilisés en serre pour des expériences à petite échelle sur les associations culturales. Une diminution significative de la ponte de la teigne du chou (Plutella xylostella L.) a été observée sur ces choux de Bruxelles.Des leurres en polystyrène vert ont été placés pour simuler l'effet des mauvaises herbes. Ils n'ont eu aucun effet sur la ponte de la teigne.L'association avec le trèfle blanc (Trifolium repens L.), comparée à celle avec le thym, a entrainé une ponte, sur choux de Bruxelles associés au trèfle significativement plus faible. On peut envisager que cette différence est due à une influence olfactive.相似文献
170.