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1.
The after-ripening response has been well documented in many plant species but studies of this topic are lacking in many new oilseed crops such as Physaria. In a factorial experiment, we tested the effect of different after-ripening periods and germination conditions on freshly harvested seeds of seven Physaria species, Physaria argyraea, Physaria fendleri, Physaria gracilis, Physaria rectipes, Physaria recurvata, Physaria sessilis, and Physaria thamnophila. The seeds were stored for 4 and 12 weeks over two saturated salt solutions (LiCl and MgCl2) to equilibrate seed moisture at three storage temperatures (5, 25, and 35 °C). We likewise tested a dormancy-breaking protocol on these species by using conditions previously recommended for use in genebanks for P. fendleri. The germination tests were conducted with light (1052 lux) and gibberellic acid (GA3) (100 ppm) and without them. Results suggested that conditions previously set for P. fendleri are also adequate for P. gracilis, P. recurvata, and P. sessilis, but may still be not optimal for the perennial species, P. argyraea, P. thamnophila, and P. rectipes. Overall, higher germination percentages were obtained with light and GA3 treatments. In all species, we observed slight differences between total germination results after 4 weeks and 12 weeks of storage, with higher values evident only in P. fendleri, P. recurvata, and P. thamnophila after their fresh seeds were subjected to 12 weeks of after-ripening at warm temperatures.  相似文献   

2.
While Lesquerella fendleri Gray (Wats.) is not yet a commercial crop, its history serves as a model for new crop development. The most important characteristic is the absence of any significant biological barriers to commercialization. Other potential crops may have valuable, high-demand products but possess traits difficult to overcome such as seed shattering or poor yield capacity. Lesquerella has a distinctive plant architecture that is conducive to seed productivity under a variety of conditions, and the trait could be further exploited. The plant also has high amounts of within-species and interspecific genetic diversity allowing breeding improvements in traits including oil quantity and quality. The unique seed oil is predominately composed of a hydroxy fatty acid, lesquerolic acid (C20:1OH), that is similar to ricinoleic acid (C18:1OH) found in castor oil. Improvements in agronomics will help increase seed yields, water use efficiency, while reducing crop production costs. New tools offered by remote sensing will help plant breeders and growers assess crop development. Defining herbicides and obtaining registrations for use in lesquerella appears to be the biggest obstacle for commercialization of this crop. The improvements in agronomics, breeding, genetics, and the expansion of new markets started in the 1980's, and has made lesquerella a viable potential crop that could utilize thousands of hectares in arid climates of the world provided research continues.  相似文献   

3.
Seeds of Lesquerella (Brassicaceae) contain oil rich in hydroxy fatty acids (HFA) that may be used in several industrial products such as motor oils, greases, plastics, cosmetics and pharmaceuticals. One of the most abundant HFA in the seed oil is lesquerolic acid, which is chemically similar to ricinoleic acid from castor (Ricinus communis L.). Hence, lesquerolic oil derived from a domestically grown crop could reduce the import of castor oil. In nature, Lesquerella grows in open and arid habitats, and therefore it may be an alternative arid-land crop. Domestication and breeding efforts warranted establishing a Lesquerella germplasm collection by the USDA-ARS, National Plant Germplasm System (NPGS). Seeds of 195 accessions (32 species) from the collection were evaluated for content of four different HFA (lesquerolic, densipolic, auricolic and ricinoleic) and seven other fatty acids (palmitic, palmitoleic, stearic, oleic, linolenic, linoleic and arachidic) by gas chromatography. The highest content of lesquerolic acid (C20:1 OH) was found in seeds of L. pallida and L. lindheimeri (average of >80%); the highest content of densipolic acid (C18:2 OH) was in seeds of L. perforata, L. stonensis, L. densipila, L. lyrata and L. lescurii (average>40%); the highest content of auricolic acid (C20:2 OH) was in L. auriculata and L. densiflora (average>30%), and the highest ricinoleic acid (C18:1 OH) content was in seeds of L. densipila, L. lescurii, L. lyrata and L. perforata (>10%). The highest percentages of the seven other fatty acids evaluated were oleic 23.8 (L. lasiocarpa), linoleic 18.7 (L. ludoviciana), linolenic 11.4 (L. cinerea), stearic 4.9 (L. densiflora), palmitic 4.7 (L. stoniensis), palmitoleic 2.8 (L. angustifolia), and arachidic 1.7% (L. gordonii and L. gracilis). Fatty-acid composition varied across species and accessions, and was likely influenced by the location and year the seeds were harvested, and by seed color. The NPGS Lesquerella collection could potentially serve as a valuable source of germplasm for the crop improvement.  相似文献   

4.
吴博  刘晓  王玲  阚云超  李丹丹 《玉米科学》2016,24(5):33-36,42
以玉米自交系昌7-2授粉后不同天数的玉米子粒为研究对象,通过实时荧光定量PCR技术,对玉米中3个Polycomb Repressive Complex 2基因(PRC2)Mez1(Maize enhancer of zeste 1)、Fie1(Fertilization independent endosperm 1)和Vef101(VEF family protein 101)在授粉后不同天数的表达情况进行研究。结果表明,Mez1、Fie1和Vef101在授粉后子粒发育不同阶段均有表达,Fie1在子粒发育过程中呈先上升后下降的趋势,授粉后10 d表达量最高,表明Fie1可能在子粒由胚胎形成到干物质积累的过渡时期发挥调控作用;Mez1在子粒发育过程中呈先下降后上升的趋势,授粉后10 d表达量最低,子粒发育后期表达量明显上升,表明Mez1可能在子粒淀粉积累过程中发挥调控作用;Vef101只在授粉后5 d的子粒中呈现高表达,其他时期表达量均较低,表明Vef101可能在玉米子粒发育早期胚胎形成过程中发挥调控作用。  相似文献   

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7.
Lesquerella is a potential new seed crop that contains hydroxy fatty acid triglycerides and approximately 15% seed coat gums. The polysaccharide gum of the Lesquerella fendleri seed was isolated and jet-cooked with cornstarch in a series of laboratory experiments to investigate the viscoelastic properties of gum-modified starch solutions. The Lesquerella gum was combined with cornstarch at 1, 5, and 10% levels to produce a jet-cooked and drum dried material with potential application as a thickening or suspension agent. Flow curves were determined for 1% solutions of jet-cooked starch and gum combinations. All materials investigated were biodegradable and exhibited positive thixotropic behavior.  相似文献   

8.
On the basis of various industrial importances of hydroxyl fatty acids we have investigated Sesbania aculeata seed oil. The most interesting finding is the presence of a hydroxyolefinic fatty acid (9.24%) along with other usual fatty acids such as lauric (2.51%), myristic (0.37%), palmitic (10.94%), palmitoleic (3.54%), stearic (4.02%), oleic (17.10%), linoleic (45.92%), linolenic (5.29%), arachidic (0.03%) and behenic (1.04%). The structure of this hydroxy fatty acid was established on the basis of spectral data (IR, 1H NMR, 13C NMR, MS) and chemical (catalytic hydrogenation, oxidative degradation) methods as (Z)-12-hydroxyoctadec-9-enoic (ricinoleic) acid.  相似文献   

9.
The utilization of Hura crepitans seed oil in the formulation of alkyd resins was investigated using a two-stage alcoholysis-polyesterification method. The percentage yield of the oil was 36.4%; and the physicochemical characterization revealed that the seed oil is an unsaturated semi-drying oil. The fatty acid profile of the oil showed that it contains linoleic acid (81.6%) as the most abundant fatty acid, and two other fatty acids: palmitic acid (16.92%) and stearic acid (1.76%). Short (I), medium (II) and long (III) oil alkyds were synthesized using the oil, glycerol and phthalic anhydride in different ratios. Properties of the three prepared samples of H. crepitans seed oil alkyds having oil content of 30% (I), 50% (II), and 65% (III) were evaluated. The alkyd resins synthesized compared favourably with the commercially available alkyd resin. The presence of unsaturation in the oil was confirmed by infra-red peak at 2930 cm−1 attributed to CC stretch. The infra-red peaks of the sample also compared well with that of the commercial sample indicating that H. crepitans seed oil has been successfully converted to alkyd resin. Evaluation of prepared alkyds by determination of acid values, solubility in butanol and toluene, resistance of dry film to acid, alkali and water, and drying time revealed that H. crepitans seed oil is a potential raw material for the coating industry.  相似文献   

10.
This investigation determined the functional properties of protein in Lesquerella fendleri seed and press cake from oil processing. L. fendleri seeds were heat-treated at 82 °C (180 °F) during 120 min residence time in the seed conditioner, and then screw-pressed to extract the oil. Unprocessed ground, defatted lesquerella seeds and press cakes were analyzed for proximate composition and protein functional properties. Protein from unprocessed lesquerella seed showed the greatest solubility (≥60%) at pH 2 and 10 and was least soluble (25%) at pH 5.5–7. Unprocessed lesquerella protein also had high surface hydrophobicity index (So), as well as, excellent foaming capacity and stability, emulsifying properties, and water-holding capacity (WHC) at pH 7. Protein solubility profile of the press cake showed up to 50% reduction in soluble proteins at nearly all pH levels, indicating heat denaturation during cooking and screw-pressing. Foaming capacity of the press cake protein decreased slightly, but foam stability was completely lost. Press cake protein also had markedly reduced values for So, emulsifying properties and WHC, further confirming lesquerella protein’s sensitivity to heat treatment.  相似文献   

11.
Payenapara lleloneura Kurz. (Kan-zaw), an endemic medicinal plant only found in Tanintharyi Region of Myanmar, is widely used in the treatment of various cancer and different ailments. In the present research, the seeds were phytochemical investigated for their nutritional potential for their use as functional foods or novel diet oil resources. Nutritional evaluation showed that the seeds are rich in fats and carbohydrates (soluble sugars and starch). Fatty acid analyses showed that the seeds accumulate very rich α-eleostearic acid (α-ESA, 18:3Δ9cis,11trans,13trans), an important conjugated fatty acid, up to more than 70 ​% of total fatty acids. The seed oil derived from the Kan-zaw tree contains approximately 3.25 ​% β-eleostearic acid (18:3Δ9trans,11trans,13trans), an unusual conjugated fatty acid that imparts a potent anticancer application and industrially important drying qualities to Kan-zaw oil. Physicochemical properties of the Kan-zaw seeds were examined; petroleum ether (60–90 ​°C) extract of seed oils were also investigated for the saponification value, iodine value and estimation of acid value. Further, the present study investigated cytotoxic potential of ethanol, methanol, acetone, chloroform Kan-zaw seed extracts and commercial Kan-zaw oil against human cervical cancer cell line (HeLa). The Kan-zaw extracts and oil have shown significant anticancer activity on HeLa cells.  相似文献   

12.
Moringa oleifera Lam. is a member of Moringaceae family which grows throughout most of the tropics, and is native to sub-Himalayan tracts of north west India, Pakistan, Bangladesh and Afghanistan. Moringa seed concentrates 35-45% oil which is considered a great natural cosmetic emollient almost total natural absence of color and odor, and high oleic acid concentration (>73%). To assess their production potential in the Arid Chaco, The Yungas Tropical Forest, Tropical Lowland Forest, and in the Sub-Humid Chaco Ecosystems of South America, a comparative trial was undertaken to determine their seed yield and oil content. Arid Chaco Ecosystem: significant (P < 0.05) difference in seed yields among years were found, with 176.17 and 481.25 kg/tree recorded for 1- and 2-year-old trees, respectively. Sub-Humid Chaco Ecosystems: the difference in seed yield and oil percentage between years was significant (P < 0.05). Comparison between years showed significantly (P < 0.05) higher seed yields, and significantly (P < 0.05) lower oil percentage for the two years old trees, than for the one year old trees. The oil/tree content was significantly (P < 0.05) higher for two years old trees than for one-year-old trees. Yungas Tropical Forest Ecosystem: seed oil percentage was significant (P < 0.05) higher in one-year-old trees than in seeds of two years old trees. Overall: over the tree years, oil percentage was significantly (P < 0.05) higher for seeds produced at the Arid Chaco than at the Sub-Humid Chaco. The seed/tree yields and the oil/tree content were no significantly (P < 0.05) different among the three ecosystems. However, when oil percentage per tree and seed yield/tree were combined trees from Sub-Humid Chaco and from Yungas Tropical Forest yielded significantly (P < 0.05) higher oil content compared to that from Arid Chaco trees.  相似文献   

13.
Lesquerella (Lesquerella fendleri) is a potential alternative crop that is being studied for commercial oilseed production. Understanding the minimum temperatures for germination and seedling growth is important for determining potential areas for lesquerella production. The objectives of this study were to determine the cardinal temperatures for germination and seedling growth, and to screen ecotypes for germination and growth characteristics. A temperature gradient table arrangement was used to observe seed germination over a range of temperatures, and time to germination and shoot appearance. Times to 5 mm root length and 5 mm shoot length were also measured to assess cardinal temperatures for seedling survival and growth. Two different species were examined, L. fendleri and a species we refer to as ‘L. pallida aff.’ because it differed from typical L. pallida plants in chromosome number and in oil quality. We concluded that both germination and growth of L. pallida aff. occurred fastest at 22 °C, whereas L. fendleri germinated earlier at 18 °C, but grew faster at 22 °C. L. pallida aff. also had lower germination than L. fendleri over the range studied. Non-dormant seeds of improved lines of L. fendleri had better performance at temperatures above 22 °C than did unimproved accessions. Lines of L. fendleri selected for high oil content and salt tolerance had similar temperature requirements for germination except for improved line WCL-LO3, the current line being used in production. This line had optimal temperatures 6 °C higher for germination and growth than the other improved lines. Accessions of L. fendleri collected from elevations above 2000 m performed better at warmer temperatures, whereas those collected from elevations below 2000 m tended to perform better at cooler temperatures. Dormant seeds of L. fendleri germinated more quickly at low temperatures and had lower base (<3 °C) and optimal (22 °C) temperatures than non-dormant seeds (>7 °C and 28 °C, respectively). We speculate that this partial dormancy trait allows populations of L. fendleri to exploit a wider range of temperature conditions in the wild in order to thrive in extreme environments.  相似文献   

14.
In the chemical investigation of marine unicellular bacteria, a new peptide, thalassospiramide G (1), along with thalassospiramides A and D (2–3), was discovered from a large culture of Thalassospira sp. The structure of thalassospiramide G, bearing γ-amino acids, such as 4-amino-5-hydroxy-penta-2-enoic acid (AHPEA), 4-amino-3,5-dihydroxy-pentanoic acid (ADPA), and unique 2-amino-1-(1H-indol-3-yl)ethanone (AIEN), was determined via extensive spectroscopic analysis. The absolute configuration of thalassospiramide D (3), including 4-amino-3-hydroxy-5-phenylpentanoic acid (AHPPA), was rigorously determined by 1H–1H coupling constant analysis and chemical derivatization. Thalassospiramides A and D (2–3) inhibited nitric oxide (NO) production in lipopolysaccharide (LPS)-stimulated mouse macrophage RAW 264.7 cells, with IC50 values of 16.4 and 4.8 μM, respectively.  相似文献   

15.
Aim of this study was to determine the content of bioactive phytochemicals in Capparis spinosa subsp. rupestris (syn. C. orientalis), a less investigated species of caper and compare the chemical profile of this species with that of other studied Capparis sp. and especially with the related cultigen C. spinosa subsp. spinosa. Chemical composition of seed oil and glucosinolates, as well as of glucosinolates and flavonoids from the aerial parts of the plant have been determined and data reported here. Oil from the plant seeds is rich in unsaturated and rare lipids such as cis-vaccenic acid; the main glucosinolate is glucocapperin. The aerial parts are characterized by rutin as the dominant flavonoid. The overall phytochemical data obtained from the analysis of C. spinosa subsp. rupestris indicate that this species represents a very rich source of bioactive compounds of nutraceutical relevance although the compositional profile does not differentiate this subspecies from C. spinosa subsp. spinosa.  相似文献   

16.
A joint Danish, Mexican, United States wild potato (Solanum sect.Petota) germplasm collecting expedition was conducted in Mexico between Aug. 21-Oct. 20, 1988. The trip resulted in 93 seed and 25 tuber collections of 18 species and one putative natural hybrid,S. xmichoacanum. Rare species collected include:Solanum darum,S. hintonii,S. lesteri, andS. xmichoacanum. First germplasm collections were made of the disjunct populations ofS. fendleri from Baja California. The potential and realized breeding value of these species is discussed.  相似文献   

17.
In separate experiments conducted in 2007 and 2008, growth and accumulation of selected caffeic acid derivatives (CADs; i.e., caftaric acid, chlorogenic acid, echinacoside, caffeic acid, cynarin, p-coumaric acid, ferulic acid and cichoric acid) were determined in Echinacea angustifolia DC. var. angustifolia seedlings grown in hydroponic culture (floating raft system) at a density of 122 plant m−2 (at planting). Plants were harvested 11 (2007) or 16 (2008) weeks after transplanting (i.e., 15 or 20 weeks after sowing). In both years, plants grew vigorously and at harvest approximately half of the plants under observation had developed one to three inflorescences. In 2008, the root yield (2940 kg ha−1) harvested in nearly eight months from two consecutive hydroponic cultures was within the yield reported in the literature for field cultivations lasting two to four years. None of the selected CADs was found in the leaves, while the inflorescences (stem and capitulum) contained only caftaric acid and echinacoside at concentrations higher than the detection limits (0.05 mg g−1 dry weight). Echinacoside, cynarin and chlorogenic acid were found in root tissues at concentrations ranging from 0.36 to 5.25 mg g−1 dry weight. In all plant samples, echinacoside, which is the marker compound for E. angustifolia material, did not reach the minimum quality standard (10 mg g−1 dry weight) for the production of standardized extract. We concluded that short-cycle, high-density greenhouse hydroponic culture stimulates plant growth and root production in E. angustifolia, but it does not ensure sufficient CADs accumulation in dried roots.  相似文献   

18.
Management practices that accelerate crop development and allow earlier harvest would be beneficial in short-season potato (Solanum tuberosum L.) production areas. Yield and quality of the potato cultivar ‘Russet Burbank’ were evaluated in a 2-yr study in northern Maine to determine effects of soil tillage and seedsprouting treatments designed to dry soil early in the spring and hasten seed emergence. The tillage treatments, consisting of fall raised bed (RB), fall ridge till (RT), and spring chisel plow (CH), were tested in combination with green-sprouted and non-sprouted seed tubers on a Caribou gravelly loam (coarse-loamy, mixed, frigid,Typic Haplorthod). Plants from green-sprouted seed emerged earlier than from non-sprouted seed tubers (87%-96% vs 21%-37%, respectively, at 18 days after planting [DAP] in 2000; and 73%-88% vs 18%-23%, respectively, at 20 DAP in 2001). Green-sprouted seed tubers in RB yielded 4.6 to 5.9 T ha-1 more than nonsprouted seed tubers in RB. However, non-sprouted seed tubers yielded higher than green-sprouted seed tubers in RT by 2.9 to 4.2 T ha-1 and in CH by 1.1 to 4.1 T ha-1. Similarly, green-sprouted seed tubers in RB and nonsprouted seed tubers in RT and CH produced higher marketable yield, greater tuber length, and greater tuber diameter than the corresponding seed-sprouting treatment. In the comparatively wetter year (2000), the use of green-sprouted seed tubers in RB significantly increased total and marketable yields, and produced longer and larger tubers than all other treatments. However, in 2001 (relatively dry year), yield and quality from green-sprouted seed tubers in RB did not differ from non-sprouted seed in RT or CH. Green-sprouted seed produced fewer sunburned and rotten tubers, but more misshapen tubers than non-sprouted seed in RB tillage. The technique of producing Russet Burbank potatoes in raised beds is a promising system in regions with short growing seasons for enhancing early soil drainage during spring and improving soil water retention during critical periods of crop growth and development.  相似文献   

19.
Seedborne fungi can reduce survival, growth, and yield of maize (Zea mays L.). Laboratory, field, and growth chamber experiments were conducted to determine the effects of the seed treatment fungicides fludioxonil, mefenoxam, and azoxystrobin on germination, plant population, and grain yield of maize grown from low-quality hybrid seed infected with seedborne fungal pathogens. Study I used seed of four hybrids infected at 0-54% incidence with Fusarium spp., Stenocarpella maydis, Penicillium spp., Rhizopus spp., and/or Aspergillus spp. Study II used three seed lots for each of two hybrids infected at 7-37% incidence with S. maydis. Warm and cold germination for untreated seed varied among hybrids in both studies. Warm germination of the seed lot with the highest incidence of S. maydis in study II treated with azoxystrobin and fludioxonil was significantly greater (+7%) than the nontreated control. Plant population in study I was significantly affected by seed treatment, hybrid, and their interactions. Populations were greater (≥9%) for fludioxonil, fludioxonil + mefenoxam, and fludioxonil + mefenoxam + azoxystrobin treatments compared to controls. In growth chamber experiments with pasteurized soil, emergence (≥5%) and plant dry weight (≥14%) were both greater than controls only with the triple seed treatment. Plant populations in study II for all seed treatments except mefenoxam and azoxystrobin alone were greater (≥4%) than controls. Yield in study I was significantly affected by hybrid and seed treatment. Yield for one hybrid was higher (≥20%) than the control with all seed treatments except fludioxonil, whereas yield with another hybrid was consistently greater (≥26%) only with the triple seed treatment. Yield in study II was significantly affected by hybrid, seed treatment, and their interactions. Yield was greater (≥8%) than the controls for all seed treatments with one hybrid and with all (≥5%) except azoxystrobin for the other hybrid. Highest yields occurred with the triple seed treatment. Results indicate that fludioxonil and azoxystrobin can increase germination, population, and yield of maize grown from seed infected by S. maydis and other fungi.  相似文献   

20.
A marine-derived strain of Clonostachys rosea isolated from sediments of the river Loire estuary (France) was investigated for its high lipid production. The fungal strain was grown on six different culture media to explore lipid production changes. An original branched conjugated fatty acid, mainly present in triglycerides and mostly produced when grown on DCA (23% of total fatty acid composition). It was identified as 4-Me-6E,8E-hexadecadienoic on the basis of spectroscopic analyses. This fatty acid reduced viability of MCF-7 breast cancer cells in a dose dependent manner (up to 63%) at physiological free fatty acid human plasma concentration (100 μM). Reduction of gene expression of two lipogenic enzymes, the acetyl CoA carboxylase (ACC) and the fatty acid synthase (FAS) was evaluated to explore the mechanisms of action of 4-Me-6E,8E-16:2 acid. At 50 μM, 50% and 35% of mRNA gene expression inhibition were observed for ACC and FAS, respectively.  相似文献   

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