首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 608 毫秒
1.
Starch grain, phytolith and cereal bran fragments were analyzed in order to identify the food remains including cakes, dumplings, as well as porridge unearthed at the Astana Cemeteries in Turpan of Xinjiang, China. The results suggest that the cakes were made from Triticum aestivum while the dumplings were made from Triticum aestivum, along with Setaria italica. The ingredients of the porridge remains emanated from Panicum miliaceum. Moreover, direct macrobotantical evidence of the utilization of six cereal crops, such as Triticum aestivum, Hordeum vulgare var. coeleste, Panicum miliaceum, Setaria italica, Cannabis sativa, and Oryza sativa in the Turpan region during the Jin and Tang dynasties (about 3rd to 9th centuries) is also presented. All of these cereal crops not only provided food for the survival of the indigenous people, but also spiced up their daily life.  相似文献   

2.
Leaf waxes from Panicum miliaceum, P. texanum and Setaria italica have been analysed; the principal components are hydrocarbons, esters, al  相似文献   

3.
Archaeobotanical studies were undertaken at the Yuergou site, which is located in the Turpan basin in Xinjiang, China, and which has been dated to around 2300–2400 years b.p. Altogether 21 taxa were identified. Four cereal remains were identified, Triticum aestivum, Hordeum vulgare var. coeleste, Panicum miliaceum and Setaria italica. The first three were probably cultivated while the last one may not have been grown deliberately, but probably grew together with plants of P. miliaceum. A fruit stone of Ziziphus jujuba (Chinese date) was discovered, which showed that this may have been cultivated around the site during that time. Charcoal of Picea sp. was found, from wood which must have been used as fuel by the indigenous people. Fifteen taxa of wild plants were also identified, most of which can be considered as weeds, and which grew near the site. Burs of Xanthium strumarium were discovered. As nearly all of them were broken, the seeds may have been used by the ancient inhabitants. Since most of the cereal remains consisted of chaff, they must represent by-products. Furthermore, grains of Echinochloa crus-galli may also have been exploited as complementary food resources. All the above indicate that both cultivated and wild plants were used for cereals, fuel, or other purposes, and plant resources played important roles in the daily life of the ancient inhabitants of the Yuergou site.  相似文献   

4.
Tannins are plant-derived polyphenols with antimicrobial effects. The mechanism of tannin toxicity towards Escherichia coli was determined by using an extract from Acacia mearnsii (Black wattle) as a source of condensed tannins (proanthocyanidins). E. coli growth was inhibited by tannins only when tannins were exposed to oxygen. Tannins auto-oxidize, and substantial hydrogen peroxide was generated when they were added to aerobic media. The addition of exogenous catalase permitted growth in tannin medium. E. coli mutants that lacked HPI, the major catalase, were especially sensitive to tannins, while oxyR mutants that constitutively overexpress antioxidant enzymes were resistant. A tannin-resistant mutant was isolated in which a promoter-region point mutation increased the level of HPI by 10-fold. Our results indicate that wattle condensed tannins are toxic to E. coli in aerobic medium primarily because they generate H2O2. The oxidative stress response helps E. coli strains to overcome their inhibitory effect.  相似文献   

5.
The Weed-Broomcorn Millet,Panicum miliaceum L. subsp.ruderale (Kitag.)Tzvelev, until now observed only in Asiatic countries, is also present in Austria (C. Europe). Whereas the cultivatedP. miliaceum subsp.miliaceum, devoid of all natural dispersal ability, cannot actively spread, the Weed-Broomcorn Millet can do so successfully and is increasingly infesting fields ofZea mays. Its spikelets disarticulate at maturity below the glumes, and moreover the florets disarticulate above the sterile floret by means of an abscission layer just beneath a swelling body which developes from the upper rachilla segment. All facts and findings are in favour of the assumption that the Weed-Broomcorn Millet is a product of repeated reverse mutations inP. miliaceum subsp.miliaceum.  相似文献   

6.
Nervonic acid (NA) is a very-long-chain monounsaturated fatty acid with pharmaceutical and nutraceutical functions that plays an important role in treating several neurological disorders. One major source of NA is plant seed oil. Here we report fatty acid profiles of seeds and germplasm diversity of six plant species, including three woody plants with high amounts of NA-enriched seed oil, Malania oleifera, Macaranga adenantha, and M. indica. M. oleifera had the largest seed (average 7.40 g single seed), highest oil content (58.71%), and highest NA level (42.22%). The germplasm diversity of M. oleifera is associated with its habitat but not elevation. Seeds of M. adenantha contained higher NA levels (28.41%) than M. indica (21.77%), but M. indica contained a significantly higher oil content (29.22%) and seed yield. M. adenantha germplasm varied among populations, with one population having seeds with high oil content (22.63%) and NA level (37.78%).Although M. indica grow naturally at a range of elevations, no significant differences were detected between M. indica populations. These results suggest that M. indica and M. oleifera have greater potential as a source of NA, which will contribute to constructing a germplasm resource nursery and establishing a selection and breeding program to improve the development of NA-enriched plants.  相似文献   

7.
Talbot JM  Finzi AC 《Oecologia》2008,155(3):583-592
Tannins are abundant secondary chemicals in leaf litter that are hypothesized to slow the rate of soil-N cycling by binding protein into recalcitrant polyphenol–protein complexes (PPCs). We studied the effects of tannins purified from sugar maple, red oak, and eastern hemlock leaf litter on microbial activity and N cycling in soils from northern hardwood–conifer forests of the northeastern US. To create ecologically relevant conditions, we applied tannins to soil at a concentration (up to 2 mg g−1 soil) typical of mineral soil horizons. Sugar maple tannins increased microbial respiration significantly more than red oak or hemlock tannins. The addition of sugar maple tannins also decreased gross N mineralization by 130% and, depending upon the rate of application, decreased net rates of N mineralization by 50–290%. At low concentrations, the decrease in mineralization appeared to be driven by greater microbial-N immobilization, while at higher concentrations the decrease in mineralization was consistent with the formation of recalcitrant PPCs. Low concentrations of red oak and hemlock tannins stimulated microbial respiration only slightly, and did not significantly affect fluxes of inorganic N in the soil. When applied to soils containing elevated levels of protein, red oak and hemlock tannins decreased N mineralization without affecting rates of microbial respiration, suggesting that PPC formation decreased substrate availability for microbial immobilization. Our results indicate that tannins from all three species form recalcitrant PPCs, but that the degree of PPC formation and its attendant effect on soil-N cycling depends on tannin concentration and the pool size of available protein in the soil.  相似文献   

8.
In 1986 in Western Australia, cucumber mosaic virus (CMV) infection was widespread in breeders' selections of narrow-leafed lupin (Lupinus angustifolius), and in collections of lupin cvs and wild L. angustifolius lines. When seed of some of these selections and cvs was sown, seed-borne CMV was detected in seedlings. Infection of F1 progenies was traced to use of infected parent plants. CMV was also widespread in 25 seed crops of the new lupin cv. Wandoo but not in 42 seed crops of the new cv. Danja. When samples of the seed sown in 1986 were tested, CMV was detected in 3 - 34% of seedlings of cv. Wandoo but in none of cv. Danja. Following intensive roguing of symptom-bearing plants in the 1986 seed crop of new lupin cv. Gungurru, the level of seedling infection with CMV in seed samples after harvest was 0·1-0·2%. CMV was detected in 6 - 8%, 0·6-5% and 0 - 18% of seedlings from seed samples of established lupin cvs Chittick, Yandee and Illyarrie respectively. Highest levels of seed transmission were in seed from crops grown in high rainfall areas. When a sample of cv. Wandoo seed was graded for size by sieving, CMV was detected in seedlings grown from seed in all grades, but the smallest grade contained the highest level of infection. When seed was collected from pods at different positions on plants in a CMV-infected crop of cv. Illyarrie, seed from primary pods transmitted the virus to seedlings at a 3% rate, seed from first order lateral pods at 8% while seed from second and third order lateral pods transmitted at 13%. Examination of CMV-infected lupin crops indicated that seed-infected plants competed poorly and tended to be shaded out in dense crops but to survive in sparse crops. In 1987 during drought conditions after seeding, plant mortality was greater with seed-infected seedlings than with healthy seedlings despite wide plant spacing. An isolate of CMV from subterranean clover (Trifolium subterraneum) induced severer symptoms in lupins than four isolates from lupin; only the subterranean clover isolate prevented seed production. In tests at one lupin breeding site, CMV was found in 15 species of weeds and volunteer legumes. Fumaria officinalis, Stachys arvensis and volunteer lupins were most frequently infected.  相似文献   

9.
Determination of Lignin and Tannin Contents of Cowpea Seed Coats   总被引:1,自引:0,他引:1  
Tannins in the seed coats of cowpea cultivars interfere withthe determination of lignin by the acetyl bromide method butthe tannins can be removed by extraction with acetone:water(70:30) allowing a direct determination on the residue. Furthermore,the difference between the absorbance values determined by theacetyl bromide method before and after the removal of tanninscan be used as a measure of tannin content in cowpea seed coats.Copyright1995, 1999 Academic Press Cowpea, Vigna unguiculata, lignin, tannin, acetyl bromide  相似文献   

10.
Panicum miliaceum L. (broomcorn millet) was an important cereal for Eurasian populations in prehistory. It was first domesticated in China and spread westwards into Central Asia and Europe later on. However, the domestication history and dispersal routes of this cereal are still not clear. The well desiccated P. miliaceum grains recovered from Xiaohe cemetery, a Bronze Age cemetery in Xinjiang, China, provide us with an invaluable opportunity to further explore this issue, especially considering Xinjiang’s critical geographical position at the crossroads of contact between the West and East. Here we present an analysis of ribosomal DNA (rDNA) internal transcribed spacer (ITS) and external transcribed spacer (ETS) sequences of P. miliaceum remains excavated from Xiaohe cemetery in comparison to modern landraces. The results show that the Xiaohe P. miliaceum exhibits heterogeneous characteristics in its rDNA, which are also commonly found in modern landraces. However, no exact sequence matching the Xiaohe millet was found in modern landraces so far, possibly suggesting the loss of genetic diversity through time. The most similar sequences are mainly present in landraces from India and Europe. Based on the genetic data of modern landraces and archaeological findings, we discuss the domestication of P. miliaceum and the possible prehistoric connections between northern China, Xinjiang and Europe in agricultural practices, as well as the potential routes westwards of P. miliaceum.  相似文献   

11.
Archaeobotanical material was recovered in two contiguous compartments of a compound in Monte Mozinho (Penafiel, northern Portugal). These areas comprise storage facilities from three different typologies—dolium, pits and above-ground quadrangular structures in the corner of the compartments. Few carpological materials were found inside the storage structures and all these are cereals which were most likely stored as clean grain. Recovered grains are probably remnants of the last stored crops prior to abandonment of the area. A radiocarbon date obtained on grains of rye positions this event at a time within the 3rd century and the beginning of the 4th century a.d. Outside the structures from compartment 2, abundant crop processing by-products, mostly weeds and chaff, were recovered. Since traditional agricultural communities tend not to waste such organic material, it is likely that it was kept in the area to be used as fodder. Data is ambiguous regarding the possible existence of fodder crops mixed with these by-products. Overall, there is a predominance of millets (Panicum miliaceum and Setaria italica) and rye (Secale cereale), but naked wheat (Triticum aestivum) is also a relevant crop. The presence of oat (Avena) is significant but it is difficult to interpret due to its exclusive presence alongside weeds and chaff. Grape pips (Vitis vinifera) were also found, but these are rare. The Late Roman carpological material from Monte Mozinho is of great relevance on a regional level. It documents and dates the presence of rye and testifies to a multifunctional system in which plant husbandry and animal breeding were intertwined.  相似文献   

12.
In this study, phyto-constituents, anti-bacterial and anticancer activity of Azadirachta indica A. Juss and Melia azedarach Linn was analyzed. High Performance Liquid Chromatography (HPLC) and Thin Layer Chromatography (TLC) fingerprint profile of methanol extract of A. indica and M. azedarach was carried out. The present findings showed the presence of phytochemicals such as, steroids, alkaloids, phenols, flavonoids, saponins, tannins, anthraquinone and aminoacids in A. indica and M. azedarach extracts. HPLC profiling of methanolic extract of A. indica and M. azaderach revealed eleven and ten fractions of compounds were visualized in the form of peak. In TLC methanolic extract of A. indica was separated by eight distinct phenolic and three steroidal bands and M. azaderach showed sixteen distinct phenolic and three different steroidal bands. In antibacterial activity, Among the various extracts 50 µg/ml methanolic extracts of A. indica showed high activity against K. pneumoniae (14 mm) and M. azedarach showed high activity against S. aureus (15 mm). The results suggest that the crude methanolic extracts of A. indica and M. azedarach possess significant phytochemical properties compared to other extracts and hence the phytochemicals of M. azedarach and A. indica can be exploited for plant based anticancer and antimicrobial agents in the near future.  相似文献   

13.
Intercellular distribution of enzymes involved in amino nitrogen synthesis was studied in leaves of species representing three C4 groups, i.e. Sorghum bicolor, Zea mays, Digitaria sanguinalis (NADP malic enzyme type); Panicum miliaceum (NAD malic enzyme type); and Panicum maximum (phosphoenolpyruvate carboxykinase type). Nitrate reductase, nitrite reductase, glutamine synthetase, and glutamate synthase were predominantly localized in mesophyll cells of all the species, except in P. maximum where nitrite reductase had similar activity on a chlorophyll basis, in both mesophyll and bundle sheath cells. NADH-glutamate dehydrogenase was concentrated in the bundle sheath cells, while NADPH-glutamate dehydrogenase was localized in both mesophyll and bundle sheath cells. The activities of nitrate-assimilating enzymes, except for nitrate reductase, were high enough to account for the proposed in vivo rates of nitrate assimilation.  相似文献   

14.
In the current study; insecticidal, growth regulation, oviposition deterrence and repellency of petroleum ether extracts of Azadirachta indica, Penganum harmala, Datura stramonium, Tribulus terrestris and Chenopodium murale against 2nd instar larvae of housefly was investigated. Five different concentrations (5%, 10%, 15%, 20% and 25%) were used through larval feeding and the mortality data was recorded after 24, 48 and 72 hrs. Highest mortality was induced by P. harmala (63.87%) followed by D. stramonium (62.78%), A. indica (53.84%), T. terrestris (41.86%) and C. murale (4.09%) after 72 h at 25% concentration, respectively. Increased mortality was observed with increased time duration and concentration. Longest larval duration (9.33 ± 0.33 days) and pupal duration (7.33 ± 0.33 days) days) was recorded in larvae treated with 25% concentration of P. harmala which also caused a decrease in the activity of AChE, ACP, AKP, α-Carboxyl, and β-Carboxyl enzymes. However, at 25% concentration, C. murale showed highest oviposition deterrence activity (81.88%) followed by D. stramonium (79.58%). In comet assay test, at highest concentration (25%) the mean comet tail lengths represented by Penganum harmala, Datura stramonium and Azadirachta indica (Reference plant) were 10.20 ± 0.49, 9.20 ± 0.37 and 7.80 ± 0.49 μm while percent DNA damage was 10.56 ± 0.77, 10.67 ± 1.62 and 8.11 ± 0.85% respectively compared to controls cells. Phytochemical analysis indicated the presence of flavonoids, steroids, saponins, cardiac glycosides, tannins, alkaloids, terpenoids and anthraquinones. Fourier Transform Infrared spectroscopy (FTIR) analysis revealed the presence of phenolic flavonoids, saponins, tannins as major functional groups. Further studies are needed to explore and thus, to incorporate weed plant extracts for the management of house flies.  相似文献   

15.
Bundle sheath cells were enzymatically isolated from representatives of three groups of C4 plants: Zea mays (NADP malic enzyme type), Panicum miliaceum (NAD malic enzyme type), and Panicum maximum (phosphoenolpyruvate (PEP) carboxykinase type). Cellular organelles from bundle sheath homogenates were partially resolved by differential centrifugation and on isopycnic sucrose density gradients in order to study compartmentation of photosynthetic enzymes. A 48-h-dark pretreatment of the leaves allowed the isolation of relatively intact chloroplasts. Enzymes that decarboxylate C4 acids and furnish CO2 to the Calvin cycle are localized as follows: NADP malic enzyme, chloroplastic in Z. mays; NAD malic enzyme, mitochondrial in all three species; PEP carboxykinase, chloroplastic in P. maximum. The activity of NAD malic enzyme in the three species was in the order of P. miliaceum > P. maximum > Z. mays. There were high levels of aspartate and alanine aminotransferases in bundle sheath extracts of P. miliaceum and P. maximum and substantial activity in Z. mays. In all three species, aspartate aminotransferase was mitochondrial whereas alanine aminotransferase was cytoplasmic. Based on the activity and localization of certain enzymes, the concept for aspartate and malate as transport metabolites from mesophyll to bundle sheath cells in C4 species of the three C4 groups is discussed.  相似文献   

16.
Changes in seed quality (assessed by potential longevity, i.e.the value of the seed lot constant K1 of the seed viabilityequation) in three contrasting cultivars of rice (Oryza sativaL.) were monitored during seed development and maturation intwo temperature regimes, viz 28/20°C and 32/24°C (12/12h), provided by controlled environments. Mass maturity (definedas the end of the seed-filling phase) varied only between 18and 20 d after 50% anthesis. In five of the six treatment combinationsmaximum potential longevity was not achieved until 12-19 d aftermass maturity. In contrast, the maximum potential longevityof seeds of a japonica rice cultivar produced in the warmerregime was obtained in the first harvest after mass maturity.After mass maturity, the potential longevity of the japonicarice seed lots produced in the warmer environment was much lessthan that for the cooler environments. Maximum potential longevitywas also consistently greater in the cooler than the warmerregime for the two indica cultivars, although the differencein K1 was small (0·3-0·5). The deleterious effectof increase in temperature on seed quality development was notdetected until after mass maturity. Maximum potential longevityin the cooler regime was greatest in the glutinous indica (K1= 3·9) and least in the japonica cultivar (K1 = 3·1).It is concluded that the japonica cultivar is not as well adaptedto warm seed production regimes as the indica cultivars. Consequently,subject to confirmation, this research suggest that the seedproduction of japonica cultivars for long-term genetic conservationshould be undertaken, whenever possible, in warm temperate environments.Copyright1993, 1999 Academic Press Oryza sativa L., rice, genebanks, seed development, seed storage, seed longevity, temperature  相似文献   

17.
In this study, 56 F1 crosses of B. napus, including their eight parents, were developed through complete diallel mating design. Analysis of variances (ANOVA) of combining ability showed very highly significant (P ≤ 0.01) values for the general combining (GCA), specific combining (SCA) and the reciprocal combining ability (RCA) towards yield and its associated traits. Parental lines, AUP-9 (3.51), AUP-18 (37.26), AUP-20 (0.12), AUP-7 (0.11), and AUP-18 (5.66), were found as the best general combiners for each of the traits: pods on main raceme, pods on individual plant, seeds on each pod, 1000 seed weight and seed yield plant?1, respectively, whereas, based on desirable SCA effects, crosses found best were AUP-14 × AUP-18, AUP-14 × AUP-20, AUP-8 × AUP-20, AUP-2 × AUP-18, AUP-2 × AUP-14, and AUP-2 × AUP-9 for pods main raceme?1, pods plant?1, seeds pod?1, 1000 seed weight and seed yield plant?1, respectively. Superior reciprocal hybrids for economically important traits such as pods main raceme?1, pods plant?1, seeds pod?1, and seed yield plant?1 were AUP-17 × AUP-9, AUP-14 × AUP-2, AUP-18 × AUP-7 and AUP-20 × AUP-8, respectively, involving at least one best general combiner (parental line). Estimates of combining ability variances and predictability ratio (σ 2GCA/σ 2SCA <1.00) revealed the preponderance of a non-additive gene action and was further confirmed by higher values of variances due to SCA than GCA.  相似文献   

18.
A significant body of recent research shows that the first east–west transmission of cereal crops, Triticum spp. (wheat) and Hordeum spp. (barley) from the west and millets (Setaria italica, foxtail millet, and Panicum miliaceum, common millet) from the east, took place sometime around the start of the 5th millennium bp, with part of the most likely route lying along the Tianshan mountains in northern Xinjiang, China. Here the dominant economic adaptation is, and was in prehistory, not crop-based agriculture but transhumant pastoralism. The site of Luanzagangzi (ca. 3,300–2,900 cal bp) on the northern slope of the Tianshan is one of only a handful of Bronze Age sites in Xinjiang with evidence for well-established crop cultivation. In this paper, we report on ten samples collected for phytolith analysis from a 4 m deep profile at Luanzagangzi. The results show evidence that a range of cereal crops was being grown (multi-cropping), Triticum spp., Hordeum spp., Setaria italica and Panicum miliaceum. Pooideae, Paniceae woody plants, Phragmites (reed) and Cyperaceae (sedges) were presumably also exploited for subsistence purposes in this area. We speculate that the strategy of growing a range of crops, wheat/barley, common millet and foxtail millet was adopted by the Bronze Age population in this region as a supplement to herding. The findings of this study help us to understand the dispersal of cultivation strategies across the Eurasian steppe via the Xinjiang region, and the communication between China and the West in the late Bronze Age.  相似文献   

19.
Adult organs of Struthanthus vulgaris, a very common mistletoein south east Brazil, present relatively high amounts of condensedtannins. In adult organs, tannins are found as large intracellulardeposits. In leaves, tannic deposits are more common in palisadeand midrib parenchyma. The cortex of the stem and root containsmany cells with tannic deposits. The wood of both organs containsintracellular deposits almost completely confined to the parenchymarays. Tannins of the adult fruits are localized in the viscinlayer surrounding the seed. The content of tannins in 10-d-oldseedlings is low, but increases rapidly with development. Thearea that will give rise to the lysigenous gland in the youngroot also presents tannic intracellular deposits. The secondaryhaustorial system presents intracellular tannins in the zoneof contact with the host.Copyright 1993, 1999 Academic Press Struthanthus vulgaris, Loranthaceae, mistletoe, tannins, histological localization  相似文献   

20.

Background and aims

(i) compare the concentrations of total polyphenols (TP) and condensed tannins (CT), and CT profiles in different organs of mature trees and seedlings of eight true mangrove species in Hong Kong; (ii) examine the antioxidant activities of CT and (iii) relate the non-enzymatic antioxidative defence system with the vertical zonation pattern of mangrove species.

Methods

Mature trees and seedlings of eight species were collected from a Hong Kong mangrove swamp to determine TP and CT concentrations and the antioxidant activities of CT.

Results

According to TP concentrations, the true mangrove species could be broadly classified into three groups, (i) Lumnitzera racemosa and Aegiceras corniculatum > (ii) Heritiera littoralis, Excoecaria agallocha, Bruguiera gymnorrhiza and Kandelia obovata > (iii) Acanthus ilicifolius and Avicennia marina. The last two are pioneer species in the most foreshore location. They also had significantly lower antioxidant activities, CT concentrations and different CT profiles than the other six species in mid- and low-tides.

Conclusions

Classification of the eight true mangrove species into three groups based on polyphenols was similar to their vertical zonation from land to sea. The relationships between these antioxidants and zonation should be further verified by transplantation studies.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号