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1.
Tetraploid Grindelia camporum was selected for increased crude resin yield for a period of 2 yr. The observed response to selection, 0.8% of the aboveground dry weight/yr, was highly significant. Differences in resin yield between plants at different phenological stages were also highly significant. The selected line showed some signs of inbreeding depression in comparison to a control line, including lower dry-weight production and higher mortality.  相似文献   

2.
Two diploid taxa, Grindelia procera and G. camporum, and 3 tetraploid ones, G. camporum, G. hirsutula, and G. stricta, have been studied to ascertain their interrelationships. Meiosis in diploid parental strains was regular, the common chromosome configuration being 5 rod bivalents and 1 ring bivalent. The average chiasmata frequency per chromosome was 0.60. Pollen fertility was about 90% in all strains examined. Diploid interspecific hybrids had normal meiosis with an average chiasmata frequency of 0.56 per chromosome. No heterozygosity for inversions or interchanges was detected, and pollen fertility was above 85%. Meiosis in parental tetraploid strains was characterized by the presence of quadrivalents in addition to a complementary number of bivalents. The average chiasmata frequency per chromosome was 0.59 and pollen fertility was generally about 80%. Tetraploid interspecific hybrids also had quadrivalents, normal meiosis, and high pollen fertility. Close genetic relationships between the diploids and between the tetraploids are indicated, and geographical, ecological, and seasonal barriers to gene exchange exist. Attempts to obtain hybrids between diploids and tetraploids were successful in a few cases. The hybrids were tetraploid and had normal meiosis and fertility similar to parental and F1 tetraploids. Their origin was by the union of unreduced gametes of the diploid female parent and normal pollen from the tetraploid parent. On the basis of chromosome homology, normal meiosis, plus high fertility exhibited in the diploid, tetraploid, and diploid X tetraploid interspecific hybrids, these species of Grindelia are considered to be a part of an autopolyploid complex. Gene exchange between diploids and diploids, tetraploids and tetraploids, and diploids and tetraploids is possible. Tetraploid G. camporum may have originated by hybridization between G. procera and diploid G. camporum with subsequent doubling of chromosomes and selection for the combined characteristics of the diploids.  相似文献   

3.
Zavala  Jorge A.  Ravetta  Damian A. 《Plant Ecology》2002,161(2):185-191
UV-B radiation is absorbed effectively by nucleic acids and other sensitive targets, potentially causing harmful photochemical effects. Protection against UV-B radiation may be afforded by flavonoids and other phenolics, which absorb strongly in the UV region, but little is known about the role played by other compounds, such as terpenes. Grindelia chiloensis, native of Patagonia (Argentina), can accumulate as much as 25% resin (terpenes) in its leaves. The present investigation was carried out to test the effect of solar UV-B radiation on the allocation of photoassimilates to biomass and terpenes. Exposure to UV-B radiation reduced whole plant biomass, plant height and leaf area, and increased leaf thickness and resin accumulation in Grindelia chiloensis. Higher absorbance was found for refined resin in the UV-B waveband from plants grown under solar UV-B radiation than plants without UV-B radiation. These chemical and structural changes could protect the plant from UV radiation, and may help elucidate the importance of epicuticular resins for a species as G. chiloensis native to an environment with maximum daily integrated values of solar UV-B irradiance.  相似文献   

4.
Rosin is a well recognised skin sensitiser and is also amongst the most common causes of occupational asthma. Due to its complex chemical composition, it is difficult to isolate its many components and this has hindered progress in the identification of the specific respiratory and contact allergens it contains. This paper reports the application of high-performance liquid chromatography and other analytical techniques to the isolation and identification of contact allergens in complex mixtures such as rosin. HPLC methods were developed in order to isolate as many rosin components as possible and these were then patch tested on rosin sensitive individuals. The structure of the most dermatologically active component was then determined using mass spectrometry, nuclear magnetic resonance and infrared techniques. An HPLC method has also been developed which will enable the identification of rosin in commercial products, providing a valuable tool for determining the cause of rosin contact allergy. Furthermore, mass spectral data for the common abieitic-type resin acids are compiled which were used to confirm the identification of the HPLC resin acid peaks and have not been reported previously.  相似文献   

5.
Oleoresin (pitch) is a defensive secretion composed of monoterpene olefins (turpentine) and diterpene resin acids (rosin) that is produced in grand fir (Abies grandis Lindl.) stems in response to wounding. Monoterpene and diterpene biosynthesis are coordinately induced in wounded stems as determined by monitoring the activity of monoterpene and diterpene cyclases, as well as two cytochrome P450-dependent diterpenoid hydroxylases involved in the formation of ([mdash])-abietic acid, the principal resin acid of this species. The activity of these enzymes reaches maximum levels that are 5- to 100-fold higher than those of nowwounded control stems 10 d after wounding and this is followed by a synchronous decline. The increase in biosynthetic activity is consequently followed by the accumulation of a viscous mass of resin acids, with the loss of the volatile monoterpenes, at the site of injury. The observed coordinate induction of monoterpene olefin and abietic acid bio-synthesis and the results of oleoresin analysis are consistent with the role of the volatile monoterpenes as a solvent for the mobilization and deposition of resin acids at the wound site to seal the injury with a rosin barrier after the evaporation of the turpentine. The last step of resin acid biosynthesis is catalyzed by an operationally soluble aldehyde dehydrogenase that is not inducible by wounding but seemingly is expressed constitutively at a high level. In vivo [14C]acetate feeding and resin analysis indicate that this enzyme is not efficiently coupled to the earlier steps of the pathway.  相似文献   

6.
In the four species studied, Grindelia stricta ssp. blakei, G. arizonica, G. lanceolata, and Prionopsis ciliata (Haplopappus ciliatus), the female gametophyte develops according to the Polygonum (normal) type from the chalazal megaspore of a row of four. In most cases only two antipodal cells are formed, the micropylar one originally containing two nuclei. The number of nuclei increases in both cells; one or both antipodal cells typically grow laterally into the integument, often extending to near the surface of the ovule. This resembles the condition previously reported in Grindelia squarrosa. Since the four species of Grindelia have similar antipodal outgrowths, such outgrowths may be considered typical for this genus. The fact that Prionopsis resembles Grindelia in regard to outgrowths from the antipodal cells and differs in this respect from typical Haplopappus helps to justify its separation from Haplopappus, and perhaps its suggested merger with Grindelia.  相似文献   

7.
The stem content of diterpene resin acids (rosin) increases dramatically following wounding of grand fir (Abies grandis) saplings, but the level of monoterpene olefins (turpentine) in the stem decreases following injury, in spite of a significant increase in monoterpene cyclase (synthase) activity. However, this observation was explained when rapid evaporative losses of the volatile monoterpenes from the wound site was demonstrated by trapping experiments, a finding consistent with a role of turpentine as a solvent for the mobilization and deposition of rosin to seal the injury. Mature forest trees responded to stem wounding by the enhancement of monoterpene cyclization capacity in a manner similar to 2-year-old grand fir saplings raised in the greenhouse. Light and water stresses greatly reduced the constitutive level of monoterpene cyclase activity and abolished the wound-induced response. The diminution in monoterpene biosynthetic capacity was correlated with a dramatic decrease in cyclase protein as demonstrated by immunoblotting. Relief of stress conditions resulted in the restoration of cyclase activity (both constitutive and wound induced) to control levels. The results of these experiments indicate that grand fir saplings are a suitable model for studies of the regulation of defensive oleoresinosis in conifers.  相似文献   

8.
Ten populations of 4N Grindelia camporum (Asteraceae) were investigated in a common-garden study of phenotypic and genetic variability. This species is a long-lived perennial herb and an obligate outcrosser which would be expected to display considerable gene flow among populations based on its life-history traits. Each of the 17 morphological, phenological, and physiological traits examined showed significant differences between populations. Average within-population heritability was 0.39. The variation between populations averaged 3.3 times the variation within populations, indicating that the populations are well-differentiated for each of the 17 traits. Two possible explanations for the differentiation are given: populations may have diverged from a common ancestor in very little geologic time, or the species may have a polytopic origin.  相似文献   

9.
This article documents the addition of 283 microsatellite marker loci to the Molecular Ecology Resources Database. Loci were developed for the following species: Agalinis acuta; Ambrosia artemisiifolia; Berula erecta; Casuarius casuarius; Cercospora zeae-maydis; Chorthippus parallelus; Conyza canadensis; Cotesia sesamiae; Epinephelus acanthistius; Ficedula hypoleuca; Grindelia hirsutula; Guadua angustifolia; Leucadendron rubrum; Maritrema novaezealandensis; Meretrix meretrix; Nilaparvata lugens; Oxyeleotris marmoratus; Phoxinus neogaeus; Pristomyrmex punctatus; Pseudobagrus brevicorpus; Seiridium cardinale; Stenopsyche marmorata; Tetranychus evansi and Xerus inauris. These loci were cross-tested on the following species: Agalinis decemloba; Agalinis tenella; Agalinis obtusifolia; Agalinis setacea; Agalinis skinneriana; Cercospora zeina; Cercospora kikuchii; Cercospora sorghi; Mycosphaerella graminicola; Setosphaeria turcica; Magnaporthe oryzae; Cotesia flavipes; Cotesia marginiventris; Grindelia Xpaludosa; Grindelia chiloensis; Grindelia fastigiata; Grindelia lanceolata; Grindelia squarrosa; Leucadendron coniferum; Leucadendron salicifolium; Leucadendron tinctum; Leucadendron meridianum; Laodelphax striatellus; Sogatella furcifera; Phoxinus eos; Phoxinus rigidus; Phoxinus brevispinosus; Phoxinus bicolor; Tetranychus urticae; Tetranychus turkestani; Tetranychus ludeni; Tetranychus neocaledonicus; Tetranychus amicus; Amphitetranychus viennensis; Eotetranychus rubiphilus; Eotetranychus tiliarium; Oligonychus perseae; Panonychus citri; Bryobia rubrioculus; Schizonobia bundi; Petrobia harti; Xerus princeps; Spermophilus tridecemlineatus and Sciurus carolinensis.  相似文献   

10.
报道中国东北辽宁省发现的菊科(Asteraceae)紫菀族(Astereae)一个新归化属胶菀属(Grindelia)。它在外形上接近于旋覆花属(1nula),但区别在于胶菀属花药基部钝,花柱分枝顶端附属物呈披针形或三角形,冠毛鳞片状。依据在中国所采集的标本描述了该属在中国的唯一代表种胶菀(Grindelia squarrosa)的形态特征,并讨论了其自然分布和进入中国的可能途径。  相似文献   

11.
树脂酸及其衍生物的生物活性   总被引:1,自引:0,他引:1  
树脂酸是松香的主要组分,在工业上具有广泛的应用。近年来,研究表明树脂酸及其衍生物具有重要的生物学功能,包括抗氧化、消炎等活性。本文综述了这些化合物的生物活性。  相似文献   

12.
Grindelia coronensis, a new species from the Meseta del Somuncura, Prov. Río Negro, Argentina, is described and illustrated. It is similar toG. chiloensis (Cornel.) Cabrera but it is readily distinguished by its leaves which are conspicuosly differentiated into a obovate blade and a long petiole.  相似文献   

13.
Yao K  Wang J  Zhang W  Lee JS  Wang C  Chu F  He X  Tang C 《Biomacromolecules》2011,12(6):2171-2177
We have carried out the synthesis of side-chain rosin-ester-structured poly(ε-caprolactone) (PCL) through a combination of ring-opening polymerization and click chemistry. Rosin structures are shown to be effectively incorporated into each repeat unit of caprolactone. This simple and versatile methodology does not require sophisticated purification of raw renewable biomass from nature. The rosin properties have been successfully imparted to the PCL polymers. The bulky hydrophenanthrene group of rosin increases the glass-transition temperature of PCL by >100 °C, whereas the hydrocarbon nature of rosin structures provides PCL excellent hydrophobicity with contact angle very similar to polystyrene and very low water uptake. The rosin-containing PCL graft copolymers exhibit full degradability and good biocompatibility. This study illustrates a general strategy to prepare a new class of renewable hydrocarbon-rich degradable biopolymers.  相似文献   

14.
An acid fraction of the dichloromethane extract of Grindelia squarrosa and a neutral fraction of the ethyl acetate extract of Grindelia camporum yielded a number of previously known grindelane diterpenoids and flavonoids. Along with the known isolates, two new grindelane diterpenoids, 13-isogrindelic acid and 17-grindeloxy grindelic acid, from G. squarrosa were isolated and identified spectroscopically.  相似文献   

15.
The aim of this study was to formulate a sustained release system for indomethacin (IND) with rosin gum obtained from a pine tree. Rosin microparticles were prepared by a dispersion and dialysis method without the addition of surfactant. In order to investigate the influence of solvents on the formation of colloidal microparitcles, various solvents like ethanol, DMF, DMAc, and acetone were used. The rosin microparticles containing IND were characterized by X-ray diffractometry (XRD) and differential scanning calorimetry (DSC). The morphologies of rosin microparticles observed by scanning electron microscopy (SEM) were spherical. The solvents used to dissolve rosin significantly affected the drug content and drug release rate of IND. The release behaviors of IND from the rosin microparticles were dependent on the drug content and size of the particles. Rosin microparticles with a higher drug content and of a larger particle size had a slower drug release rate. Also, the IND release rate from the rosin microparticles could be regulated by the rosin content in the microparticles. From these results, rosin microparticles have the potential of being used as a sustained release system of IND.  相似文献   

16.
Abstract: Lignin, a biopolymer formed in the cell walls of plants, is a by-product of paper manufacturing. In research at IBM, it was incorporated into a resin used in the fabrication of printed wiring boards (PWB) for the microelectronics industry. The resin had physical and electrical properties similar to those of current laminate resins. PWBs fabricated from the lignin-based resin passed most of the standard physical, electrical, and reliability tests for an "FR4"-grade laminate. A comparison of the lignin-based resin and current resins via life-cycle assessment indicated up to 40% lower energy consumption for the biobased resin. Large-scale manufacture of lignin-based resins would require an inexpensive source of lignin with low ionic contamination.  相似文献   

17.
Agricultural production in the arid Southwest is heavily dependent upon water for irrigation. If current trends of water use continue, the amount of water available to agriculture in the year 2000 will only meet approximately 50% of the needs of currently available irrigated crop land. Development of new crops with low irrigation needs is of highest priority. None of the major crop plants of the world is well adapted to arid lands. However, in the Sonoran Desert, more than 375 species of noncultivated food plants have been identified, and approximately 40 of these served as major local food resources for native people in the region. Research and development of new crops must address the issues of water use, productivity, chemical composition, and quality. Domestication of native species that have evolved and became adapted to arid conditions in the Southwest is considered to be a good strategy. Research and development programs on such native, new crops as guayule, jojoba, and buffalo gourd are well underway. New domestication programs involvingCuphea species for medium-chain fatty acids,Lesquerella species for hydroxy fatty acids,Grindelia camporum for resin production, and interspecific hybrids ofBaccharis for landscape plant materials are described. The role of the USDA Agricultural Research Service, state agricultural experiment stations, and industry in the development of new crops is discussed.  相似文献   

18.
Membrane chromatography has been established as a viable alternative to packed-bed column chromatography for the purification of therapeutic proteins. Purification via membrane chromatography offers key advantages, including higher productivity and reduced buffer usage. Unlike column chromatography purification, the utilization of high-throughput screening in order to reduce development times and material requirements has been a challenge for membrane chromatography. This research focused on the development of a new, high-throughput screening technique for use in screening membrane chromatography conditions for monoclonal antibody purification. The developed screen utilizes a 96-well plate format, thereby allowing for the screening of multiple different membrane conditions at once. For this study, four mixed-mode cation exchange membranes and one cation exchange membrane were evaluated on the plate. The screen is performed in a similar manner to that of a resin slurry plate screen, however, instead of a single loading step, the antibody feed was loaded in 50 mg/ml increments up to a maximum loading of 450 mg/ml. Performing a similar, incremental loading on a resin plate would be impractical, as mixing times are substantially longer due to pore diffusion limitations. However, due to the significantly faster rate of mass transfer for membranes relative to resin, mixing times could be reduced by up to a factor of sixty on the membrane plate. Additional optimization showed that higher hydrophobicity can potentially lead to slower kinetics and mixing times that may need to be adjusted accordingly. The end result is a screen that has been proven to provide results comparable to those obtained on larger-scale membrane purification runs while also enabling exploration of a much greater operating space and significantly reducing the feed materials required.  相似文献   

19.
溴化马来松香的合成、表征及其阻燃性的研究   总被引:1,自引:0,他引:1  
本文以马来松香与液溴加成,合成了溴化马来松香;研究了反应温度、原料的摩尔比、反应时间等因素对反应过程及产物性能的影响.用FT-IR、1H NMR和TG对溴化马来松香进行了表征.结果表明,当反应温度为-2~6℃,反应时间5~6 h,反应物的当量配比约为1.2时,收率可达87.9%.溴化马来松香具有较好的阻燃性,同时也拓宽了松香的应用范围,提高了松香的附加值.  相似文献   

20.
The aerial parts of Grindelia stricta afforded in addition to known compounds 21 diterpenes, all closely related to grindelic acid. The aerial part  相似文献   

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