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甘蔗染色体组构成系统演化的研究 总被引：14，自引：1，他引：13
用核型分析方法对甘蔗祖亲种、含两物种血缘栽培种、含三物种血缘栽培种、含四物种血缘栽培种染色体组型的系统演化特征进行了研究．从祖荣代野生种向高代杂交栽培种（含两物种血缘以上）系统演化的基本特征是：染色体数目、异染色质含量相对增加,易位现界普遍存在,中部着丝点染色体所占比例逐渐减少,核型从对称向不对称方向演化。野生种和栽培种的染色体数目分别为2n=68－92和2n=90－120;染色体约对长度为1．56－6．38μm,相对长度为1．03－4．01;染色体主要为中部着丝点染色体,少数为亚中部及亚端部着丝点染色体,未见端部着丝点染色体;除春尼为1B核型外,其余6个品种（印度割手密、墨车里本、POJ2875、Co419、F134和ROC10）全为2B类型．分别以印度割手密和春尼基因组DNA为探针,对栽培种Co419进行染色体原位杂交,结果表明,Co419（2n＝114）染色体组构成中,有6条来源于割手密种,12条来源于印度种,96条为热带种或种间重组染色体． 相似文献
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海南山栏稻体细胞染色体数与普通栽培水稻相同，即２ｎ＝２４，并同属２Ｂ核型。山栏稻染色体组中有９对中部着丝点染色体（水稻对照品种为５－６对），１－２对亚中部着丝点染色体（水稻为４－５对），１－２对亚端部着丝点染色体。这表明山栏稻核型比水稻更为对称。山栏稻染色体组的异染色质含量平均为４６．１％，低于水稻对照（平均为５０．１％）。异染色质在染色体上的分布形式与水稻对照基本相同，多数是位于着丝点两侧（或两 相似文献
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采用常规压片的方法制备16个红掌品种的染色体标本,并进行核型分析。结果表明:16个红掌品种的染色体数目比较恒定,均为2n=2x=30。染色体主要由m染色体(中部着丝点区染色体)和sm染色体(亚中部着丝点区染色体)组成;最长染色体与最短染色体之比为1.83~3.07,平均臂比为1.95~2.29,臂比大于2的比例为43%~83%,核型不对称系数(As.K)为64.04%~68.17%,从核型类型来看,主要集中在2B型和3B型,只有‘紫公主’为1A型。从核型分类上看,这些种类都属于较对称的类型。 相似文献
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3种野生茄和1个栽培茄的核型分析 总被引：2，自引：0，他引：2
分析3种野生茄和1个栽培茄品种染色体核型.结果表明:所有供试材料的染色体数目均为2n=24,核型类型均为"2A"型:染色体主要由中部着丝点和近中部着丝点染色体组成,属较对称核型.但它们的核型也具有明显差异, "04E28"的核型公式为2n=16m+6sm+2st,核不对称系数60.20%;04E42的核型公式为2n=14m+8sm+2T,核不对称系数65.91%;07E67的核型公式为2n=18m+6sm,核不对称系数59.68%;栽培品种.04E08"的核型公式为2n=22m+2sm.核不对称系数58.59%. 相似文献
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甘蔗和斑茅远缘杂交后代的染色体遗传分析 总被引：4，自引：0，他引：4
对斑茅、Badila及甘蔗与斑茅杂交后代进行染色体计数与核型分析,探讨斑茅后代的染色体遗传。结果表明,海南斑茅92-105和92-77的体细胞染色体数均为2n=60,30对染色体全部为中部着丝点,臂比均在1.70以下,最长染色体与最短染色体长度之比小于2,属原始的1A型染色体。参试的甘蔗无性系的核型均属2B型。来自组合Badila(2n=80)海南斑茅92-105(2n=60)的杂种崖城96-66染色体数目为2n=70,染色体以n n的方式进行遗传;来自组合Badila×海南斑茅92-77(2n=60)的杂种崖城96-40染色体数目也为2n=70,杂种以n n的方式进行遗传;这些结果表明甘蔗斑茅杂交后代染色体以n n的方式进行遗传。 相似文献
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用Giemsa染色法分析了爪哇香茅(Cymbopogon winterianus Jowitt)的染色体组型。结果表明,除具有随体的第5对染色体为亚中部着丝点染色体外,其余9对染色体均为中部着丝点染色体,其组型为2n=20=18m十2sm(SAT)。用Giemsa C—带技术观察了爪哇香茅的染色体带型。发现其全部10对染色体着丝点的两侧都显示C—带,大多数染色体显末端带,个别染色体显中间带和副缢痕带,第2、3、4、5、8、9、10对染色体各对的两个成员之间Giemsa带型相同,而第1、6、7对染色体各对的两个成员之间带型有差异。 相似文献
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花生属野生种的核型分析及其进化 总被引：1，自引：0，他引：1
本文研究了花生属六个区组的九个种,结果表明:除A.correntina和A.rigonii两个种没有随体外,其它二倍体种都有1—2对随体。除了A.batizocoi和A.villosulicarpa没有明显小的染色体外,其它种都有一对明显小的染色体。花生区组中具有“A”染色体组的三个种和缘脉区组的一个种的染色体全部是中部着丝点染色体,其它种有1—3对亚中部着丝点染色体。A.glabrata的染色体数为40,其核型不及栽培种对称,有3对亚中部着丝点染色体,没有“B”染色体。A.batizocoi与花生区组中的其它二倍体的核型差异较大,遗传距离也大,说明其进化程度高。五个区组二倍体种的进化程度,从低到高的顺序是:花生区组(具“A”染色体组的二倍体种→A.batizocoi)→缘脉区组→三籽粒区组→直立区组→围脉区组。 相似文献
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特用油料植物紫罗兰核型和减数分裂的研究 总被引：1，自引：1，他引：0
特用油料植物紫罗兰［Matthiolaincana（L．）B．Br．］核型和减数分裂的研究结果表明;紫罗兰的染色体组分（2n）由3对中部着丝点,4对亚中部着丝点染色体组成。核型公式为2n＝14＝6m＋8sm。减数分裂的终变期7条二价体的构型明显,是环状、棒状和十字形等。到中期Ⅰ棒状二价体增多,环状二价体减少。后期Ⅰ、Ⅱ均观察到染色体桥。 相似文献
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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
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《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
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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
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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
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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
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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