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1.
Previously, the Northern Regional Research Center (NRRC) has studied chemical and botanical features of about 800 plant species in a program to identify potential renewable sources of industrial raw materials. In this program, another 64 species from northwestern and southwestern Ohio were studied for the present report. Aboveground samples were quantitatively analyzed for moisture, ash, crude protein, “oil,” “polyphenol,” and “hydrocarbon.” Plant oils were examined for classes of constituents. Oils were saponified and analyzed for yields of organic acids and unsaponifiable matter. Hydrocarbons were examined for the presence of rubber, gutta, and waxes. Rubber and gutta were analyzed for weight-average molecular weight and molecular weight distribution. Data are presented for 8 species of the 64 that gave the higher chemical yields.Rhus typhina gave outstanding yields of oil (6.5%) and polyphenol (30.8%) (moisture- plus ash-free basis).Liatris aspera yielded substantial amounts of oil (4.7%) and polyphenol (22.7%), whereasCornus racemosa yielded a substantial amount of oil (4.4%) but a more typical yield of polyphenol (11.0%).Nuphar advena andEpilobium angustifolium had considerable amounts of polyphenol (16.2, 16.3%) but little oil.Nuphar advena contained the most crude protein (24.8%). Noteworthy amounts of hydrocarbon were extracted fromCalamagrostis canadensis (1.1%),Aster umbellatus (0.8%), andSolidago riddellii (0.7%). Polyisoprenes in the hydrocarbon fractions of the latter 3 species were identified as gutta for C. canadensis and rubber forA. umbellatus andS. riddellii. Botanical features of the 8 species are briefly discussed.  相似文献   

2.
Previously, the USDA Northern Regional Research Center has examined 600 plant species in 88 families for their multipurpose, energy-producing potential. About three-fourths of these species have been from central and southern Illinois, but only about 2% have been from arid or semiarid regions of the United States. For this report, 100 species collected from Arizona were evaluated, bringing the total number of species evaluated at this Center to 700 in 96 families. Plant specimens were analyzed for yields of fractions referred to as “oil,” “polyphenol,” “hydrocarbon,” and protein and were examined for botanical characteristics. Oil and hydrocarbon fractions of selected species were partially characterized. Ten species gave high yields of oil and/or polyphenol. For example,Asclepias linaria yielded 8.7% oil (dry, ash-free sample basis) + 11.7% polyphenol (1.9% hydrocarbon).Rhus choriophylla yielded 7.0% oil + 20% polyphenol (0.4% hydrocarbon) andJuglans major yielded 7.0% oil + 9.4% polyphenol (0.2% hydrocarbon).Pittosporum tobira gave the highest yield of hydrocarbon (23%). Fourteen species contained at least 18% protein. In general, the percentages of species yielding substantial amounts of oil and/or polyphenol were considerably higher for the Arizona species than for those 600 species previously analyzed. Complete analytical data are presented for 38 species and are discussed in relationship to the 600 species previously reported.  相似文献   

3.
The USDA Northern Regional Research Center (NRRC) has previously studied chemical and botanical characteristics of about 1,000 plant species in efforts to identify potential new plant sources for industrial raw materials. For this report, an additional 51 species were collected from Tennessee and studied. Above-ground plant samples were analyzed for yields of oils, polyphenols, hydrocarbons, protein, and ash. Oils were examined for the presence of seven classes of lipids and analyzed for yields of fatty acids and unsaponifiable matter. Hydrocarbons were examined for the presence of rubber, gutta, and waxes. Rubber and gutta were analyzed for average molecular weight (MW) and MW distribution. Chemical and botanical data are presented for eight of the 51 species. A checklist of the 43 other species is given; data on these are available from NRRC.Lapsana communis yielded the most oil (6.1%; dry, ash-free, plant sample basis).Ilex montana yielded the most polyphenol (21.5%) plus 4.5% oil.Agrimonia parviflora and Catalpa bignonioides gave substantial yields of polyphenol (20.0% and 17.9%, respectively), andPassiflora incarnata contained the most apparent protein (19.8%).Chrysopsis graminifolia, Solidago erecta, andVerbesina alternifolia were identified as rubber-producing species with 0.4-0.7% hydrocarbon.  相似文献   

4.
Analyses of extracts from whole-plant samples revealed that Garrya flavescens and Garrya wrightii produced gutta (trans-1,4-polyisoprene) as the major hydrocarbon in yields of 1.2 and 0.4 %, respectively. The average MWs of gutta were 142000 for G. flavescens and 10000 for G. wrightii. These species also yielded moderate amounts of ‘oil’ and ‘polyphenol’. To our knowledge, these are the first species of Garryaceae reported to produce gutta.  相似文献   

5.
6.
《Acta Oecologica》2008,33(3):337-342
Predation of herbivorous Lepidoptera larvae by insectivorous avifauna was estimated on Lindera benzoin in edge and interior habitats at two sites in eastern Pennsylvania (USA). Clay baits modeled after Epimecis hortaria (Geometridae) larvae, the primary herbivore of L. benzoin at our study sites, were used to estimate predation by birds. In both habitat types, models were placed on uninjured L. benzoin leaves as well as on leaves that had prior insect herbivore damage. Rates of model attack were greater, and model longevity reduced, in forest edge plots compared to interiors. Naturally occurring herbivore damage on L. benzoin was greater in forest interiors. However, model attack was not significantly greater on leaves with prior herbivory damage, suggesting that birds do not effectively use this type of leaf damage as a cue in their foraging. Our findings are consistent with a contribution of bird predation towards top-down control of herbivory in this system. We further discuss these results in a broader context considering the possible effects of habitat type on leaf quality, leaf defense, and herbivore performance.  相似文献   

7.
Twenty-eight taxa of Helianthus collected throughout the United States and grown in afield nursery were evaluated for yields of oil, polyphenol hydrocarbon, protein, and ash in above-ground biomass. Hydrocarbons were examined for the presence of rubber, gutta, and waxes. Rubber and gutta were analyzed for weight-average molecular weight (ìw) and molecular weight distribution (MWD). Helianthus ciliaris had the highest oil yield (3.7%) and was analyzed for yield of fatty acids and unsaponifiable matter. Most taxa had low polyphenol yields (<10%), with H. strumosus having the highest (13.9%). Helianthus salicifolius yielded the most hydrocarbon (1.6%) and H. ciliaris had the highest protein content (13.4%). Natural rubber was present in 13 species of wild sunflowers. Helianthus maximiliani had the lowest ìw (29.8 x 103), while H. laevigatus had the highest (73.3 x 103). The MWD of rubber from sunflowers were within the range of those for commercial rubbers. The lower molecular weight rubbers may have potential as plasticizing additives in commercial processing of synthetic polyisoprenes and as hydrocarbon feedstock for a synthetic petroleum industry.  相似文献   

8.
Differences in selection patterns among habitats can alter the distribution of genetic diversity even when this is estimated with neutral markers. For plants, light is an essential resource that can influence both abiotic and biotic components of habitat. We examined genetic differentiation between sun and shade habitats in Lindera benzoin L. (Spicebush), a perennial understory shrub. Genetic diversity of 127 plants from sun and shade habitats in two populations of L. benzoin was determined using 12 polymorphic microsatellite markers. We analyzed patterns of genetic diversity using analysis of molecular variance (AMOVA), and we assessed correlation between genetic and geographic distance using Mantel tests. We found (1) low levels of differentiation among populations (F ST = 0.028), (2) little evidence of genetic structure within populations due to isolation-by-distance, and (3) some evidence of habitat-based genetic differentiation. Specifically, the AMOVA showed a small (0.5%) but significant portion of overall variation could be explained by differences between habitats. The overall low levels of differentiation we saw were likely a result of extensive gene flow in this dioecious, bird-dispersed species.  相似文献   

9.
Recent work suggests that germination inhibition via allelopathy may be an important component of some species’ invasion ecology. We conducted four germination assays to test the inhibitory potential of Amur honeysuckle (Lonicera maackii), a problematic invasive shrub. The subject species in the first assay, Festuca arundinacea, exhibited a significant delay in germination when treated with extract from ground honeysuckle foliage. In the second assay, two concentrations of L. maackii extract were created by soaking foliage. F. arundinacea germination was not significantly influenced by the treatments while germination in Impatiens wallerana was substantially decreased. The third assay compared the impact of foliar extract from honeysuckle, with the native shrubs Lindera benzoin and Asimina triloba using F. arundinaceae, I. wallerana, Coreopsis lanceolata and Poa pratensis as subject species. In this assay, I. wallerana was strongly inhibited by L. maackii foliage; however, none of the other species were significantly influenced by the treatments. In the fourth assay, fruit extracts from L. maackii and L. benzoin were applied to the same four subject species. L. maackii fruit extract had an inhibitory influence on seed germination of all subject species, and inhibition from L. benzoin was also noted. Across all assays, there was a mixed reaction to extract from L. maackii and co-occurring native species that was species-specific and dependent upon the extract source. Our findings provide support for the idea that L. maackii has allelopathic activity, but further work is needed to (i) understand how broad the impact may be across the wide variety of species that are found in its invasion range and (ii) substantiate that the allelopathic effect has relevance in field environments.  相似文献   

10.
The influence of light on coral reef communities has been studied in the merchant harbour of Eilat (Red Sea), where other parameters of the local ecosystem remain relatively constant. The harbour pier is supported over a length of about 550 m by eight rows of concrete pillars. Water current is parallel to the pillar rows. Benthic animals and algae settle on the pillars, between the sun-exposed first and the extremely shadowy eighth row, according to the light gradient (about 13 – 0.1% of the light intensity above the surface). The observations were carried out from January, 1970 to March, 1971. In the most common species (28 animals and five algae), four settlement zones can be distinguished: (a) “bright zone” (13 – 3% of the light intensity measured above the water surface) withTridacna maxima, T. squamosa andPadina pavonia and some stone corals as indicators; (b) “dim-light zone, bright” (3 – 1%) withSiphonochalina siphonella andDendronephthya species as indicators; (c) “dim-light zone, dark” (1 – 0.4%) withAcabaria biserialis andClathraria rubrinodis as indicators; (d) “dark zone” (0.4 – 0.1%) with violetLithothamnion andLithophyllum species as indicators. The distribution of animals in the horizontal light gradient (rows 1–8) corresponds to that in the vertical light gradient in coral reefs; this has been verified by SCUBA diving to 40 m depth near Eilat, Dahab, and Sharm el Sheikh on the Sinai coast, and Aqaba on the Jordanian coast of the Gulf. Light intensity is the dominant ecological factor which affects the distribution of the majority of species in the reef.  相似文献   

11.
A flagellated predator of the chlorophyte algaDunaliella spp. was examined by light and electron microscopy. Although this predator had previously been identified as a species of the kinetoplastid genusBodo, the present study revealed the flagellate to be indistinguishable fromColpodella pugnax, the type-species for its genus. The flagellate lacks a kinetoplast, a microtubule supported cytopharynx and paraxial rods in the flagella — characters universally found in kinetoplastid flagellates. The cell has mitochondria with vesicular cristae. Multiple membranes surround the cell and are underlain by longitudinal microtubules not originating from the flagellar region. Most notably, the flagellate has micropores and an apical complex including a conoid, sacculate rhoptries and, apparently, a polar ring. This study hs confirmed thatColpodella is the genus with free-living species most closely related to the apicomplexan parasites (i.e. the “Euapicomplexa” andPerkinsus). No unambiguous synapomorphy supports an “apicomplexan parasites” clade: Inclusion ofColpodella is necessary to secure the Apicomplexa as a monophyletic (=holophyletic) taxon. A new family, the Colpodellidae, is erected for this genus. Colpodella turpis, a previously undescribed species that also consumesDunaliella spp., was isolated from the same samples asC. pugnax. A diagnosis for this species is presented together with a brief review of the genus, in which we recognise seven species. The generic namesAlphamonas Aléxéieff,Nephromonas Droop andDingensia Patterson & Zölffel are rendered into synonomy withColpodella.  相似文献   

12.
Microsatellite markers were developed for conservation genetic studies of Lindera melissifolia (pondberry), a federally endangered shrub of southern bottomland ecosystems. Microsatellite sequences were obtained from DNA libraries that were enriched for the (AC)n simple sequence repeat motif. From 35 clone sequences, 20 primer pairs were designed and evaluated. Eleven primer pairs amplified polymorphic marker loci in pondberry while two did so in Lindera benzoin (spicebush). In 46 samples from a single pondberry site the number of microsatellite alleles ranged from two to 11 per locus with observed heterozygosity values of 0.07–0.91.  相似文献   

13.
Two species are included in barnyard millet:Echinochloa utilis andE. frumentacea. These differ from each other in their genomic constitution and phylogeny. The former species originated fromE. crus-galli probably in eastern Asia, and is grown in Japan, Korea, and the northeastern part of China; the latter originated fromE. colona probably in tropical Asia, and is grown in Pakistan, India, and Nepal. “Japanese barnyard millet” is suggested as a suitable English common name forE. utilis; “Indian barnyard millet,” forE. frumentacea. In the past, Japanese barnyard millet was important in Japan as the staple food crop in districts where soil, weather conditions and irrigation systems were not suitable for paddy rice cultivation. When the rice crop suffered serious cool weather damage, the millet relieved people from starvation, especially in northeastern Japan. But the acreage devoted to the millet gradually decreased during and after the 1880s. Only the northern part of Iwate Prefecture is an exclusive Japanese barnyard millet cropping region at present. The breeding of cool- weather- resistant rice varieties and improvements in rice- growing techniques are mainly responsible for the decrease in acreage of the millet.  相似文献   

14.
The gerreid species,Gerres baconensis (Evermann &; Seale),G. equulus Temminck &; Schlegel andG. oyena (Forsskål), were re-assessed as valid following examination of their holotypes and other specimens, and included in the “G. oyena complex”.Gerres haconensis is currently known only from Bacon, Luzon Island, Philippines and the Ogasawara (=Bonin) Islands, Japan, andG. equulus only from southern Japan (except Ryukyu Islands) and southern Korea.Gerres oyena is widely distributed in the Indo-West Pacific (in Japan, only from the Ryukyu Islands).Gerres baconensis differs from bothG. equulus andG. oyena in having higher counts of both the pored lateral line scales (39–42 vs 35–41 in the latter two species) and the lower gill raker series (8 or 9 vs. usually 7). A U-shaped premaxillary groove, formed on the dorsum of the forehead by the long ascending processes of the premaxillae, is scaleless inG. equulus andG. oyena, whereas it is fully scaled just behind the level of the posterior nostrils inG. baconensis over ca. 160 mm in standard length (SL) (partially scaled in specimens of ca. 100 mm SL).Gerres equulus differs fromG. oyena in having the posterior margin of the maxilla not extending beyond a vertical through the anterior margin of the inner dermal eye opening, shorter second dorsal and anal fin spines (means 18.5% and 8.5% of SL, respectively vs. 21.2% and 10.3% of SL), lower body depth at first anal fin spine base (27.0% vs. 29.6% of SL) and dorsomedial U-shaped groove scaleles throughout life (vs. tiny squamation anteriorly in specimens over ca. 130 mm SL). OtherGerres species of uncertain status and/or related species are discussed.  相似文献   

15.
Twenty-nine laticiferous taxa of Apocynaceae, Asclepiadaceae, and Sapotaceae were screened for suitability as alternative sources of renewable energy, rubber, and phytochemicals and to select the most promising ones for large-scale cultivation. Of these,Allamanda violacea (14.9% protein, 13.8% polyphenol, 8.6% oil, 3.2% hydrocarbon),Catharanthus roseus (15.4% protein, 10.4% polyphenol, 11.5% oil, 1.9% hydrocarbon), andHolarrhena antidysenterica (14.2% protein, 16.4% polyphenol, 5.4% oil, 4.8% hydrocarbon) of Apocynaceae;Asclepias curassavica (19.3% protein, 6.5% polyphenol, 3.9% oil, 2.0% hydrocarbon), Calotropis gigantea (18.5% protein, 6.8% polyphenol, 7.0% oil, 2.8% hydrocarbon) of Asclepiadaceae;Mimusops elengi (11.3% protein, 9.7% polyphenol, 7.2% oil, 4.0% hydrocarbon) of Sapotaceae show promising potential for future petrochemical plantations; of all these taxa,Holarrhena antidysenterica yielded an unusually high percentage (4.8%) of hydrocarbon fraction followed byMimusops elengi (4.0%). NMR spectra confirmed the presence of cis-polyisoprene in all species studied exceptNerium indicum (white-flowered var.). These data indicate that the majority of the species under investigation may be considered for large-scale cultivation as an alternative source of rubber, intermediate energy, and other phytochemicals.  相似文献   

16.
One hundred and seven species of randomly-collected Leguminosae were evaluated for their potential as energy-producing crops. Whole plants, excluding roots, were chemically analyzed, and 11 species were identified as the more promising for future considerations based on a numerical rating system developed at this Center. Botanical, fiber, and protein characteristics of the more promising species that had ratings of less than 11 were considered excellent. Other characteristics, including contents of oil (1.7–3.2%; dry, ash-free, sample basis), polyphenol (5.4–16.5%), and hydrocarbon (0.3–0.6% for 10 species and 2.6% for one), were generally lower than those of promising species in other families previously analyzed. Of the 11 species, one contained principally rubber (polyisoprene) in the hydrocarbon fraction and 7 contained principally wax. Hydrocarbon fractions of 3 species with less than 0.4% were not examined. The oils of species with at least 3.0% oil were examined by thin layer chromatography (TLC) to determine classes of components and were given a saponification treatment to determine yields of unsaponifiable matter and fatty acids. The oil of one species was quantitatively analyzed for classes of compounds by TLC-flame ionization detection. Selected species with ratings greater than 10 are briefly discussed.  相似文献   

17.
Predation of herbivorous Lepidoptera larvae by insectivorous avifauna was estimated on Lindera benzoin in edge and interior habitats at two sites in eastern Pennsylvania (USA). Clay baits modeled after Epimecis hortaria (Geometridae) larvae, the primary herbivore of L. benzoin at our study sites, were used to estimate predation by birds. In both habitat types, models were placed on uninjured L. benzoin leaves as well as on leaves that had prior insect herbivore damage. Rates of model attack were greater, and model longevity reduced, in forest edge plots compared to interiors. Naturally occurring herbivore damage on L. benzoin was greater in forest interiors. However, model attack was not significantly greater on leaves with prior herbivory damage, suggesting that birds do not effectively use this type of leaf damage as a cue in their foraging. Our findings are consistent with a contribution of bird predation towards top-down control of herbivory in this system. We further discuss these results in a broader context considering the possible effects of habitat type on leaf quality, leaf defense, and herbivore performance.  相似文献   

18.
Thirteen species of Characeae were analyzed for their free amino acid contents. Large amounts of isoasparagine, accounting for 10 to 50% of the total free amino acids, were found in extracts fromChara (5 species including one unidentified),Nitellopsis (1 species), andLamprothamnium (1 species). In contrast, no isoasparagine was detected inNitella (5 species) andTolypella (1 species), except forN. flexilis in which as much as 40% of the free amino acids was isoasparagine. Other major amino acids found in the tested materials were Ala, Asp, Glu and Gln.  相似文献   

19.
In this study, internal transcribed spacer (ITS) regions within the nuclear ribosomal DNA of KoreanIlex were analyzed in order to investigate any molecular evidence thatI. × wandoensis could serve as a putative hybrid betweenI. cornuta andI. integra. We also sought to clearly identify taxonomic relationships and problems caused by consecutive external morphological characters among taxa in the genus. We sequenced 20 clones fromI. × wandoensis and found these individuals displayed intra-genomic polymorphisms within ITS regions. The analysis of the clones clearly demonstrated the presence of discrete sequences from bothI. cornuta andI. integra, thereby confirmingI. × wandoensis is a species that was formed by crossingI. cornuta andI. integra. Lastly, the subgenusIlex, which contains the evergreen species, failed to form a monophyletic group in a strict consensus tree that was prepared based upon ITS regions.I. crenata var.microphylla in the subgenus KoreaIlex, which has presented taxonomic problems previously, formed an independent clade within the consensus tree, thereby showing distinction fromI. crenata.) Genetic discontinuity ofI. macropoda andI. Macropoda for.pseudo-macropoda individuals couldn't be confirmed.  相似文献   

20.
In a section of the Liassic southwest of the village of Préjano (Prov. Logroño) Sinemurian Dasyclad algae were found for the first time in the “Bankkalk-Series” of the “Carniolas-Formation” which is not dated up to that time. Six species,Dissocladella lucasi (Cros & Lemoine),Dissocladella iberica nov. sp.,Dissocladella ebroensis nov. sp.,Sestrosphaera liasina Pia,Gyroporella retica (Zanin) andMacroporella nov. sp. aff. sturi Bystricky are described.  相似文献   

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