加州蓝铃花的组织培养与快速繁殖

1植物名称加州蓝铃花(Phacelia campanularia A.Gray). 2材料类别茎段和茎尖. 3培养条件(1)诱导芽萌发培养基:1/2MS(MS大量元素用量减半);(2)增殖培养基:1/2MS 6-BA 0.5mg·L-1(单位下同) NaA 0.2;(3)生根培养基:1/2MS IBA 0.2 NAA 0.2.以上培养基中均加入6 g·L-1琼脂和30 g·L-1蔗糖,pH 5.9～6.0.培养室中温度为(24±1)℃,光照时间为16 h·d-1,光照强度约为60μmol·m-2·s-1.     

Structure of anthocyanin from the blue petals of Phacelia campanularia and its blue flower color development

The dicaffeoyl anthocyanin, phacelianin, was isolated from blue petals of Phacelia campanularia. Its structure was determined to be 3-O-(6-O-(4'-O-(6-O-(4'-O-beta-d-glucopyranosyl-(E)-caffeoyl)-beta-d-glucopyranosyl)-(E)-caffeoyl)-beta-d-glucopyranosyl)-5-O-(6-O-malonyl-beta-d-glucopyranosyl)delphinidin. The CD of the blue petals of the phacelia showed a strong negative Cotton effect and that of the suspension of the colored protoplasts was the same, indicating that the chromophores of phacelianin may stack intermolecularly in an anti-clockwise stacking manner in the blue-colored vacuoles. In a weakly acidic aqueous solution, phacelianin displayed the same blue color and negative Cotton effect in CD as those of the petals. However, blue-black colored precipitates gradually formed without metal ions. A very small amount of Al(3+) or Fe(3+) may be required to stabilize the blue solution. Phacelianin may take both an inter- and intramolecular stacking form and shows the blue petal color by molecular association and the co-existence of a small amount of metal ions. We also isolated a major anthocyanin from the blue petals of Evolvulus pilosus and revised the structure identical to phacelianin.     

Development of peltate glandular trichomes of peppermint

Cryofixation and conventional chemical fixation methods were employed to examine the ultrastructure of developing peltate glandular trichomes of peppermint (Mentha x piperita). Our results are discussed in relation to monoterpene production and the mechanism of essential oil secretion. Peltate glands arise as epidermal protuberances (initials) that divide asymmetrically to produce a vacuolate basal cell, a stalk cell, and a cytoplasmically dense apical cell. Further divisions of the apical cell produce a peltate trichome with one basal cell, one stalk cell, and eight glandular (secretory) disc cells. Presecretory gland cells resemble meristematic cells because they contain proplastids, small vacuoles, and large nuclei. The secretory phase coincides with the separation and filling of the sub-cuticular oil storage space, the maturation of glandular disc cell leucoplasts in which monoterpene biosynthesis is known to be initiated, and the formation of extensive smooth endoplasmic reticulum at which hydroxylation steps of the monoterpene biosynthetic pathway occur. The smooth endoplasmic reticulum of the secretory cells appears to form associations with both the leucoplasts and the plasma membrane bordering the sub-cuticular oil storage cavity, often contains densely staining material, and may be involved with the transport of the monoterpene-rich secretion product. Associated changes in the ultrastructure of the secretory stage stalk cell are also described, as is the ultrastructure of the fragile post-secretory gland for which cryofixation methods are particularly well suited for the preservation of organizational integrity.     

The effects of ultraviolet-B radiation and intraspecific competition on growth, pollination success, and lifetime female fitness in Phacelia campanularia and P. purshii (Hydrophyllaceae)

While a considerable amount of attention has been devoted to the effects that increased ultraviolet-B (UV-B) radiation has on vegetative plant growth and physiological function, the impact that UV-B may have on plant fitness has been the focus of fewer studies, with attention given primarily to a few crop species. Further, the possible interactions between UV-B and additional potential stresses found in natural environments have rarely been studied experimentally. Because the reported effects of increased UV-B on plant growth and fitness have been highly variable, studies that focus on factors that may lead to these differences in results are important for the formulation of accurate predictions about future plant success under varying UV-B levels. We examined the effects of UV-B dose and intraspecific competition on growth, phenology, pollen production, pollination success, fruit and seed production, and offspring quality in two species of Phacelia. Increased UV-B was neutral or beneficial for all traits, while competition was neutral or detrimental. There were no significant interactions between UV-B and competition in the parental generation. Phacelia campanularia offspring were unaffected by parental competition, but derived indirect beneficial effects on germination, growth, and fitness traits from parental enhanced UV-B.     

Terpene biosynthesis in glandular trichomes of hop

Hop (Humulus lupulus L. Cannabaceae) is an economically important crop for the brewing industry, where it is used to impart flavor and aroma to beer, and has also drawn attention in recent years due to its potential pharmaceutical applications. Essential oils (mono- and sesquiterpenes), bitter acids (prenylated polyketides), and prenylflavonoids are the primary phytochemical components that account for these traits, and all accumulate at high concentrations in glandular trichomes of hop cones. To understand the molecular basis for terpene accumulation in hop trichomes, a trichome cDNA library was constructed and 9,816 cleansed expressed sequence tag (EST) sequences were obtained from random sequencing of 16,152 cDNA clones. The ESTs were assembled into 3,619 unigenes (1,101 contigs and 2,518 singletons). Putative functions were assigned to the unigenes based on their homology to annotated sequences in the GenBank database. Two mono- and two sesquiterpene synthases identified from the EST collection were expressed in Escherichia coli. Hop MONOTERPENE SYNTHASE2 formed the linear monterpene myrcene from geranyl pyrophosphate, whereas hop SESQUITERPENE SYNTHASE1 (HlSTS1) formed both caryophyllene and humulene from farnesyl pyrophosphate. Together, these enzymes account for the production of the major terpene constituents of the hop trichomes. HlSTS2 formed the minor sesquiterpene constituent germacrene A, which was converted to β-elemene on chromatography at elevated temperature. We discuss potential functions for other genes expressed at high levels in developing hop trichomes.     

Morphology and secretion of glandular trichomes in Tamus communis

Light and scanning electron microscopical investigations were carried out to study distribution, morphology and secretion of glandular trichomes during leaf development in Tamus communis . During leaf growth glandular trichomes arise continously from single protodermal cells. At maturity, they are composed of a 6-celled gland head, a secretory neck cell, an "endodermal" cell, and one basal or reservoir cell. During the early stage of secretion, several regularly arranged crater-like pores differentiate on the cuticular surface of the gland head. Through these pores (1–1.5 μm in diameter), the secretion flows out as a thin film or as rods (0.4 μm in diameter) spreading on the trichomes and on the leaf surface. Histochemical tests indicate that the secretion is composed of a small amount of carbohydrates and an abundant fraction of lipophilic material. Proceeding towards senescence, the wall degeneration of the gland head gives rise to a strong histochemical reaction for insoluble polysaccharides. The results presented are compared with those of other investigations on the pattern of secretion in glandular trichomes.     

Aphid repellent sesquiterpenes in glandular trichomes of Solanum berthaultii and S. tuberosum

Exudate from glandular trichomes of the wild potato species, Solanum berthaultii Hawkes, and the cultivated potato, S. tuberosum L., contained volatile substances including sesquiterpenes when examined with gas chromatography/mass spectrometry procedures. Sesquiterpenes were the major volatile constituents of Type A trichome exudate but were a minor constituent of Type B exudate. Sesquiterpene mixtures of the two potato species differed qualitatively and quantitatively. -Caryophyllene and E--Farnesene were major components identified in Type A trichome exudate of the cultivated potato. Sesquiterpene mixtures of both potato species were repellent to the green peach aphid, Myzus persicae (Sulzer). The role of trichome sesquiterpenes as a determinant of aphid behavior on the two potato species and in the expression of host resistance is discussed.

---

Résumé L'examen en chromatographie gazeuse et en spectométrie de masse a révélé la présence de substances volatiles contenant des sesquiterpènes dans l'exsudat des trichômes glandulaires des pommes de terre sauvage (Solanum berthaultii) et cultivée (S. tuberosum). Les sesquiterpènes étaient le principal composé volatile de l'exsudat de type A, tandis qu'ils n'étaient que faiblement représentés dans l'exsudat de type B. Les mélanges de sesquiterpènes des deux espèces différaient qualitativement et quantitativement. Le -Caryophyllène et le E--Farnesène constituaient les principaux composés identifiés dans l'exsudat de trichôme de type A de S. tuberosum. Les mélanges sesquiterpéniques des deux espèces ont repousée Myzus persicae Sulzer. La discussion a porté sur l'influence des sesquiterpènes des trichômes dans la définition du comportement des pucerons sur ces deux plantes et sur la manifestation de la résistance de l'hôte.

     

Sesquiterpene lactones from glandular trichomes of Viguiera radula (Heliantheae; Asteraceae)

In addition to known compounds, the floral parts of Viguiera radula afforded two new sesquiterpene lactones. All compounds were detected in glandular trichomes, which were micromechanically collected from the anther appendages and analyzed by HPLC. Structure identification was performed by NMR and MS techniques.     

Identification, functional characterization and developmental regulation of sesquiterpene synthases from sunflower capitate glandular trichomes

Background

Besides being essential for plant structure and metabolism, soluble carbohydrates play important roles in stress responses. Sucrose has been shown to confer to Arabidopsis seedlings a high level of tolerance to the herbicide atrazine, which causes reactive oxygen species (ROS) production and oxidative stress. The effects of atrazine and of exogenous sucrose on ROS patterns and ROS-scavenging systems were studied. Simultaneous analysis of ROS contents, expression of ROS-related genes and activities of ROS-scavenging enzymes gave an integrative view of physiological state and detoxifying potential under conditions of sensitivity or tolerance.

Results

Toxicity of atrazine could be related to inefficient activation of singlet oxygen (¹O₂) quenching pathways leading to ¹O₂ accumulation. Atrazine treatment also increased hydrogen peroxide (H₂O₂) content, while reducing gene expressions and enzymatic activities related to two major H₂O₂-detoxification pathways. Conversely, sucrose-protected plantlets in the presence of atrazine exhibited efficient ¹O₂ quenching, low ¹O₂ accumulation and active H₂O₂-detoxifying systems.

Conclusion

In conclusion, sucrose protection was in part due to activation of specific ROS scavenging systems with consequent reduction of oxidative damages. Importance of ROS combination and potential interferences of sucrose, xenobiotic and ROS signalling pathways are discussed.     

Identification, functional characterization and developmental regulation of sesquiterpene synthases from sunflower capitate glandular trichomes

Background  

Sesquiterpene lactones are characteristic metabolites of Asteraceae (or Compositae) which often display potent bioactivities and are sequestered in specialized organs such as laticifers, resin ducts, and trichomes. For characterization of sunflower sesquiterpene synthases we employed a simple method to isolate pure trichomes from anther appendages which facilitated the identification of these genes and investigation of their enzymatic functions and expression patterns during trichome development.     

Structural investigation of the glandular trichomes of endemic Salvia smyrnea L.

The morphology, anatomy and distribution of glandular trichomes on the aerial organs of Salvia smyrnea L. endemic to Turkey have been investigated with light microscopy (LM) and scanning electron microscopy (SEM). This species is evaluated in endangered (EN) category. Two morphologically distinct types of glandular trichomes were determined. Various types of capitate glandular trichomes consist of a 1–4 celled base, a 1–8 stalk celled or no stalk and a uni- or bicellular head.     

Sesquiterpene lactones and a myoinositol from glandular trichomes of Viguiera quinqueremis (Heliantheae; Asteraceae)

The extract of the floral parts of Viguiera quinqueremis afforded, in addition to known compounds, six new sesquiterpene lactones as well as a new myoinositol derivative. All compounds were detected in glandular trichomes which were collected micromechanically from the anther appendages and were analyzed by HPLC. Structure identification was performed by 1H NMR measurements including LC NMR and LC MS experiments.