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1.
为更加灵敏、高效地发现新miRNA并改进其表达差异鉴定方法,对木薯（Manihot esculenta Crantz）SC124和KU50这2个品种进行了驯化和非驯化2种干旱处理方式,利用Multiplexed RT-PCR法对2个木薯品种的8个 miRNA 进行了表达差异研究。结果表明,8个miRNA具有明显的品种、组织和时序表达特异性,较为客观真实地反映了miRNA的表达模式对胁迫信号的响应。因此,Multiplexed RT-PCR法是一种快速、高效的分析miRNA表达差异的方法,在未来miRNA的研究中有着很好的应用前景。 相似文献
2.
以干旱驯化和未驯化的香蕉幼苗为研究材料,采用实时荧光定量PCR方法检测干旱胁迫过程中6个miRNAs的表达变化。结果表明:6个miRNAs在所有香蕉幼苗的干旱胁迫响应过程中均有表达,但其表达模式存在差异,在直接干旱处理下,mi R156k、mi R160a、mi R162a、mi R164a、mi R166d的表达均呈现升高-降低的趋势,mi R397b的表达则呈现升高-降低-升高-降低的趋势;在驯化后干旱处理下,mi R156k、mi R162a、mi R166d、mi R397b的表达均呈现升高-降低的趋势,mi R160a、mi R164a的表达则呈现升高-降低-升高-降低的趋势。干旱胁迫响应过程中(除处理后第10天外),驯化后的香蕉幼苗中miRNAs的表达量基本上高于未驯化香蕉幼苗中miRNAs的表达量,同时还发现mi R160a和mi R164a的表达量都非常高。上述研究结果将为香蕉干旱胁迫应答研究奠定基础。 相似文献
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为了研究干旱胁迫木薯K+、Ca2+和ABA对干旱胁迫的响应及其变化规律,对2个品种的木薯SC124（高抗）和KU50（低抗）进行对照、驯化、非驯化旱害和驯化旱害等不同方式的干旱处理。研究发现2个木薯品种中,干旱胁迫对叶片K+和ABA的含量影响较大,而Ca2+含量变化较小;SC124在驯化和非驯化处理下的K+含量发生显著变化;ABA的含量在2个品种中的驯化干旱和非驯化干旱中变化显著,且变化趋势不同;干旱胁迫下,ABA、K+和Ca2+之间存在显著相关性。 相似文献
6.
MicroRNAs(miRNAs)是一类在植物发育调控和逆境胁迫响应过程中发挥重要功能的小RNA,为了探讨miR167e在小麦中的生物学功能,以小麦品种中国春、豫麦18和矮抗58为材料,利用RT-PCR技术克隆了小麦miR167家族基因新成员 MIR167e,并采用qRT-PCR技术分析了其时空表达特性及其对渗透胁迫的响应模式。结果将小麦 MIR167e基因定位在第5同源群染色体的短臂上,将该基因A、B和D基因组的三个部分同源基因分别命名为 TaMIR167e-5AS、 TaMIR167e-5BS和 TaMIR167e-5DS。序列分析显示,该miRNA前体区域在所检测品种间高度保守,3个部分同源基因间仅存在SNP差异,在成熟tae-miR167e对应区域完全一致。时空表达特性分析显示,tae-miR167e在籽粒发育过程中表达呈上调趋势,在不同组织间的表达差异较大,其中在3叶期,叶片和根系中表达量较高,种子中次之,穗下节中表达量最低;在干旱胁迫条件下,该miRNA受胁迫诱导而上调表达,与中国春相比,矮抗58根系中该miRNA的诱导表达启动更快,在叶片中的表达水平更高;在盐胁迫条件下,该miRNA在根系中呈下调表达趋势,而在叶片中上调表达。推测tae-miR167e在小麦发育调控和渗透胁迫响应过程中发挥重要功能。 相似文献
7.
利用Affymetrix水稻60 k芯片研究了聚乙二醇6000(PEG)模拟干旱时，水稻根系核仁小分子RNA（snoRNA）转录本的表达活性变化。在模拟干旱胁迫下，水稻根系snoRNA转录本表达有很强的品种特异性，干旱敏感品种爱华5号中共有23个snoRNA转录本活性发生变化且均表现为上调表达，而耐旱品种湘丰早119中仅有2个snoRNA转录本表达活性发生变化，也都为上调表达；转录活性发生变化的snoRNA转录本都为C/D框型，且在染色体上存在5处snoRNA簇；爱华5号和湘丰早119在模拟干旱胁迫下表达发生变化的snoRNA转录本有1个转录本重叠，且此转录本在爱华5号中表达活性是湘丰早119中的17.54倍。 相似文献
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为揭示小麦TcLr19PR2基因在信号分子和叶锈菌诱导下的表达情况,利用半定量RT-PCR方法分析了不同浓度茉莉酸甲酯(MeJA)和乙烯(ETH)诱导后于不同时间点该基因表达模式,明确MeJA和ETH最佳诱导浓度及诱导时间,同时分析了MeJA和ETH预处理后于不同时期接种叶锈菌后该基因在小麦中的表达特征。结果表明,MeJA和ETH的最佳诱导浓度分别为0.1和1.0mmol·L-1。接种叶锈菌后,TcLr19PR2基因表达量在MeJA诱导后0~3d都有明显上调,并在MeJA预处理3d后接种叶锈菌24h时TcLr19PR2基因表达量达到最大,基因表达峰值的出现要早于未接菌处理;ETH预处理3d后接种叶锈菌24h时TcLr19PR2基因表达水平开始升高,预处理10d后,接菌处理的各时间点均高于未接菌处理。以上结果说明,叶锈菌和信号分子协同作用能够显著诱导TcLr19PR2基因的表达,共同参与小麦品系TcLr19的抗叶锈病防御反应。 相似文献
10.
玉米幼苗叶表面蜡质含量及成分对干旱胁迫的响应 总被引：1，自引：1，他引：0
选用抗旱性不同的两个玉米自交系Mo17和B73为试验材料,采用盆栽控水试验,设置干旱和正常浇水两个处理,研究干旱胁迫对两个玉米品种3叶期幼苗叶面蜡质含量及成分变化的影响。结果表明,在干旱处理条件下,Mo17和B73的叶片失水率和叶绿素的抽提率均低于正常条件;两个品种叶面的蜡质含量均明显高于正常条件下的蜡质含量,且Mo17在正常和干旱条件下蜡质含量均高于B73。此外,在干旱条件下,蜡质合成相关的基因KCS、CER1、CER2、GL1、GL2和GL15的表达也明显增高。玉米叶片表面蜡质合成是应答干旱胁迫的一种重要方式,抗旱品种Mo17的抗旱性比B73要强,其表面蜡质合成较强是其中一个重要原因。 相似文献
11.
Joseph E. Laferriere Charles W. Weber Edwin A. Kohlhepp 《Plant foods for human nutrition (Dordrecht, Netherlands)》1991,41(3):277-282
Teas of plant origin traditionally consumed by the Mountain Pima of Chihuahua, Mexico, were analyzed for mineral nutritional content. Fe, Cu, Zn, Ca, and Mg composition was determined for native teas made from shoots ofTagetes lucida, T. filifolia, Elytraria imbricata, andHolodiscus dumosus, and from root xylem ofCeanothus depressus andPhaseolus ritensis. Native uses of these teas are also described. 相似文献
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Lakshman Lal 《Potato Research》1987,30(2):329-334
Summary The effects of the leaves of five plant species, one from each of the generaAmbrosia, Anemone, Eupatorium, Eucalyptus andLantana, on potato tuber moth were investigated under indigenous storage conditions at the Central Potato Research Station, Shillong
(1800 m above sea level). Their action was compared with that of a biological insecticide (spores ofBacillus thuringiensis), a chemical insecticide (carbaryl), and an untreated control. The data collected after six months storage on tuber damage,
sprout damage and the rotting indicated that the leaves ofLantana aculeata provided most protection to the tubers, reducing damage from over 70% in the check to below 5%, and sprout damage from over
45% to below 3%. Next best wasEucalyptus globulus followed byB. thuringiensis. They may be used on tubers stored for table use or for seed as they had no adverse effect on germination or on the yield
of a subsequent crop. 相似文献
14.
《Journal of Crop Improvement》2013,27(2):81-114
Summary The efficiency of N fertilizers is usually poor; often less than 50% of the applied N is taken up by the crop. This review focuses on various N fertilizers with respect to the significance of different N loss pathways, namely (i) ammonia volatilization, (ii) dinitrogen and nitrogen oxide emissions, and (iii) nitrate leaching. Further, the significance of biological N immobilization, ammonium fixation and, finally, the impact of nitrate vs. ammonium uptake on crop yield are also discussed. The reviewed literature shows that N fertilizers may differ markedly in their susceptibility to losses. There is, however, considerable scope to improve N efficiency of each N source by proper N management practices. 相似文献
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Tatiana G. Polotow Sandra C. Poppe Cristina V. Vardaris Douglas Ganini Maísa Guariroba Rita Mattei Elaine Hatanaka Maria F. Martins Eduardo F. Bondan Marcelo P. Barros 《Marine drugs》2015,13(10):6117-6137
Health authorities worldwide have consistently recommended the regular consumption of marine fishes and seafood to preserve memory, sustain cognitive functions, and prevent neurodegenerative processes in humans. Shrimp, crabs, lobster, and salmon are of particular interest in the human diet due to their substantial provision of omega-3 fatty acids (n-3/PUFAs) and the antioxidant carotenoid astaxanthin (ASTA). However, the optimal ratio between these nutraceuticals in natural sources is apparently the key factor for maximum protection against most neuro-motor disorders. Therefore, we aimed here to investigate the effects of a long-term supplementation with (n-3)/PUFAs-rich fish oil, ASTA-rich algal biomass, the combination of them, or krill oil (a natural combination of both nutrients) on baseline redox balance and neuro-inflammation indexes in cerebellum and motor cortex of Wistar rats. Significant changes in redox metabolism were only observed upon ASTA supplementation, which reinforce its antioxidant properties with a putative mitochondrial-centered action in rat brain. Krill oil imposed mild astrocyte activation in motor cortex of Wistar rats, although no redox or inflammatory index was concomitantly altered. In summary, there is no experimental evidence that krill oil, fish oil, oralgal biomass (minor variation), drastically change the baseline oxidative conditions or the neuro-inflammatory scenario in neuromotor-associated rat brain regions. 相似文献
17.
Youna Hemery Ulla Holopainen Anna-Maija Lampi Pekka Lehtinen Tanja Nurmi Vieno Piironen Minnamari Edelmann Xavier Rouau 《Journal of Cereal Science》2011
Wheat bran is a composite material made of several layers, such as pericarp, testa and aleurone. It could be fractionated into purified fractions, which might either be used as food ingredients, or serve as a starting material for extraction of bioactive compounds. The aim of this work was to evaluate the potential of using electrostatic separation as a way to obtain purified fractions from wheat bran. Ultrafine-ground bran obtained either by cryogenic grinding or by grinding at ambient temperature was used as starting material. The ultrafine bran was then charged by tribo-electrification and introduced in a chamber containing two high voltage electrodes, where bran particles were separated depending on their acquired charge, allowing positively and negatively charged fractions to be collected separately. The particle size distribution, microstructure and biochemical composition of the obtained fractions were studied. The charge of the particles was influenced by their biochemical composition: particles rich in highly branched and cross-linked arabinoxylans (pericarp) were separated from particles rich in β-glucan, ferulic acid and para-coumaric acid (aleurone cell walls). The testa and the intracellular compounds from aleurone were not highly charged, neither positively nor negatively. The most positively charged fraction represented 34% of the initial bran, and contained 62% of the ferulic acid present in the initial bran. The yield of the separation process was good (5.4% loss), and could be further increased. 相似文献
18.
M. I. Siri P. Villanueva M. J. Pianzzola L. Franco Fraguas G. Galván M. Acosta F. Ferreira 《Potato Research》2004,47(3-4):127-138
Summary The in vitro antimicrobial activity of extracts from accessions ofSolanum commersonii Dun. collected in the south of Uruguay was investigated against five microorganisms including the pathogenRalstonia solanacearum. A total of 30 extracts corresponding to organic and aqueous extracts were studied. Interestingly, most of the positive results
for growth inhibition were againstR. solanacearum. The extracts were also analyzed for the presence of glycoalkaloids and lectins. Six of the ten aqueous extracts showed lectin
presence and a wide variation in the type and amounts of glycoalkaloids, was found. Results indicate that there is no clear
relationship between the antimicrobial activity against the five microorganisms screened and the presence or amounts of lectins
and glycoalkaloids, traditionally regarded as possible antimicrobial metabolites in theSolanum genus, which indicates the presence of as yet unidentified antimicrobial compounds. 相似文献
19.
Novel food and non-food uses for sorghum and millets 总被引：4，自引：3，他引：4
Sorghum and millets have considerable potential in foods and beverages. As they are gluten-free they are suitable for coeliacs. Sorghum is also a potentially important source of nutraceuticals such antioxidant phenolics and cholesterol-lowering waxes. Cakes, cookies, pasta, a parboiled rice-like product and snack foods have been successfully produced from sorghum and, in some cases, millets. Wheat-free sorghum or millet bread remains the main challenge. Additives such as native and pre-gelatinised starches, hydrocolloids, fat, egg and rye pentosans improve bread quality. However, specific volumes are lower than those for wheat bread or gluten-free breads based on pure starches, and in many cases, breads tend to stale faster. Lager and stout beers with sorghum are brewed commercially. Sorghum's high-starch gelatinisation temperature and low beta-amylase activity remain problems with regard to complete substitution of barley malt with sorghum malt . The role of the sorghum endosperm matrix protein and cell wall components in limiting extract is a research focus. Brewing with millets is still at an experimental stage. Sorghum could be important for bioethanol and other bio-industrial products. Bioethanol research has focused on improving the economics of the process through cultivar selection, method development for low-quality grain and pre-processing to recover valuable by-products. Potential by-products such as the kafirin prolamin proteins and the pericarp wax have potential as bioplastic films and coatings for foods, primarily due to their hydrophobicity. 相似文献
20.
Tovar LR Olivos M Gutierrez ME 《Plant foods for human nutrition (Dordrecht, Netherlands)》2008,63(4):189-194
Pulque is made by fermenting the agave sap or aguamiel of Agave atrovirens with a whole array of microorganisms present in the environment including several lactic acid bacteria and yeasts such as
Saccharomyces cerevisiae. Ascorbic acid was determined in pulque and aguamiel, respectively. Phytase activity in lees, liquid and freeze-dried pulque was assayed by measuring the appearance of phosphate from phytate by a colorimetric method likewise phosphate from phytate
present in fresh corn tortilla was measured after in vitro incubation with pulque. Iron, zinc, calcium, magnesium and selenium contents were measured in pulque and corn tortilla as well as in nixtamalized corn flour (NCF), the latter is used to make instant tortilla, since corn provides
most of the energy as well as most of the phytate in the Mexican rural diet. Pulque showed phytase activity but much less ascorbic acid and iron than previously reported; additionally, phytase in pulque hydrolyzed most of phytate’s corn tortilla. Lees, which is mostly made of pulque’s microbiota, significantly accumulated iron and zinc but no selenium. NCF was fortified with iron by the manufacturers but
poorly blended. There were significant differences on selenium content between tortillas samples, apparently some soils in
central Mexico are selenium deficient. Moderate pulque intake appears to increase the bioavailability of iron and zinc bound by phytate in corn. 相似文献