花生栽培种的染色体组——1.推断染色体组供体的细胞遗传学研究

在包括着花生栽培种在内的花生属同一区系中野生二倍体种的细胞学研究表明,除一个种外,其染色体组型具有9对大染色体和1 对小染色体(‘A’)的特征。例外的一个种A.ba tizocoi具有更为一致的染色体组型。相同染色体组型二倍体种的种间杂种,具有中等的至高的花粉染色率,但在包含着A.batizocoi的杂交组合中,其杂种的花粉染色率为0,花粉母细胞的减数分裂也很不规则。这种不育的杂种,通过染色体组加倍,很可能产生可育的、稳定的双二倍体。有人提议,栽培种花生可能起源于这样一种不育的种间杂种,而从形态学和植物地理学角度来看,截至目前所搜集到的类型,最可能的染色体组的供体种是A.cardenasii和A.batizocoi。     

花生栽培种(Arachis hypogaea L.)与野生种Arachis macedoi杂种F_1细胞遗传分析

开展花生种间杂交与杂种遗传研究对于探明种间亲缘关系、创制新种质和培育新品种具有重要意义。本研究利用花生栽培品种白沙1016(2n=4X=40,AABB)与二倍体野生种A.macedoi(2n=2X=20)进行种间杂交,通过胚拯救获得种间杂种F_1植株,进而对F_1进行了分子标记鉴定、有丝分裂与减数分裂观察和基因组荧光原位杂交(GISH)分析。结果显示,杂种F_1有30条染色体,其中既有来自母本白沙1016的染色质,又有来自父本A.macedoi的染色质;A.macedoi染色体经DAPI染色显示出明亮着丝粒带且包含一对"小染色体";白沙1016的A染色体组也显示出A.macedoi基因组标记探针的杂交信号;F_1减数分裂终变期染色体平均构型为0.6 III+8.27 II+11.6 I,减数分裂I期后、末期表现为不均等分裂。以上结果表明本研究获得了新的种间杂种F_1材料,所涉及的A.macedoi可能为A染色体组物种;A.macedoi染色体与花生A染色体组发生交换产生补偿性易位的几率比较大;减数分裂后、末期染色体的不均等分裂和非四分体形成,是杂种F_1表现高度不育的重要原因之一。     

花生属种间杂种F1的雄配子发生与发育特点研究

本研究以铁矾－苏木精法和改良卡宝品红染色法对载野杂交组合父本Arachis cardenasii（二倍体）、母本铁岭四粒红（四倍体）及杂种F1根尖细胞染色体进行观察，F1为2n＝30。利用醋酸洋红压片法对野生种A.cardenasii花粉母细胞减数分裂及小孢子发育各个时期进行了观察。杂种F1的花粉母细胞减数分裂及小孢子发育与四倍体栽培种花生相比表现出一些特殊的细胞学特点：F1花粉母细胞联会复杂，染色体构型平均值为2n＝9.5Ⅰ＋6.7Ⅱ 1.8Ⅲ 0.4Ⅳ；大发细胞以15：15方式分离。存在染色单体分离提前现象；细胞核发生异型分裂，并形成了在体积上显著小于正常子细胞的小细胞，从而导致形成五分体和六分体；绝大多数小孢子的败育发生在单核居中期至单核靠边;F1 花粉萌发率低，花粉发育不正常。另外F1的部分花粉具有6个萌发孔，特别是以秋水仙素处理恢复育性的F1花粉均具有6个萌发孔。     

花生属拟直立型组(Section Erectoides)种间杂种一代及其双二倍体研究

本文研究了花生属拟直立型组(Section Erectoides)三个种(系)间多种—代及其双二倍体的形态特征、花粉母细胞减数分裂过程中染色体的联会形式及育性.结果表明,该组的染色体组已出现分化和变异,染色体结构变异可能是导致分化的重要因素之一。文中还简单地讨论了该组优良种(系)的应用前景.     

花生二倍体野生种Arachis duranensis和A. ipaensis新种间杂种的创制及鉴定

野生种Arachis duranensis（AA）和A. ipaensis（BB）是花生栽培种最可能的二倍体祖先种,而其合成的四倍体是研究花生起源与进化的重要材料。本研究利用A. duranensis系（PI 497262）和A. ipaensis（PI 468322）,通过杂交、组织培养、寡核苷酸探针染色荧光原位杂交（OS FISH）和基因组原位杂交（GISH）技术创制和鉴定了一个新的种间杂种W1824,进一步对其花粉育性、减数分裂行为和表型性状进行分析,发现W1824花粉高度不育,染色体平均构型为0.5 III + 3.5 II + 11.5 I,主茎高、侧枝长和叶面积均表现出超亲优势。表明PI 497262和PI 468322具有较高的杂交亲和性,暗示由上述两个系合成的四倍体花生可能具有显著高于亲本的生物产量和不稳定的染色体遗传方式。     

丹参三倍体育性的细胞学分析

由丹参四倍体和二倍体杂交获得丹参三倍体,三倍体植株高度不育。为探讨其育性的细胞学机制,我们采用细胞学和解剖学的方法,对其花粉母细胞发育过程中的染色体和细胞学表现进行了观测。结果表明,丹参三倍体植株生长正常,在花粉母细胞减数分裂过程中存在落后染色体、染色体不均等分向两极、染色体桥等异常现象,分裂结果产生三分体、微核等,而且花粉粒形态异常,产生畸变,萌发率极低。这些说明,丹参三倍体在生长发育过程中,由于减数分裂过程中染色体数目不平衡,在减数分裂过程中产生各种畸变、异常的染色体和细胞的行为表现,是造成其不育的主要原因。本研究为丹参三倍体育性研究提供理论依据,也为丹参育种生产实践提供指导。     

花生属中花生组与拟直立型组种间杂交研究

研究了花生属中花生组与拟直立型组３５ 个种间杂交组合的杂种胚珠和幼胚的发育状况,其中２３ 个组合为栽培种（２ｎ＝ ４ｘ）×拟直立型组野生种（２ｎ＝ ２ｘ）,１２ 个组合为花生组野生种（２ｎ＝ ２ｘ）与拟直立型组野生种杂交。所有组合的杂种均在发育过程的某一阶段发生败育,但组合间差异较大,野生种之间杂种胚的发育状况一般好于栽培种与野生种的杂种胚,共观察到３ 种不同的败育类型。采用胚珠和幼胚离体培养方法,成功地克服了种间杂交不亲和性,在９ 个杂交组合中首次获得杂种一代幼苗,移栽后有５ 个组合的杂种植株存活下来,并相继开花。对这些杂种后代的花粉育性、结实性、形态特征及花粉母细胞分裂过程进行了全面分析,证实了杂种的真实性。杂种胚珠和幼胚离体培养的成功,为进一步拓宽远缘杂交的亲本范围和更好地利用宝贵的野生花生资源,提供了有效的技术途径。     

几类异质小麦雄性不育系育性恢复的染色体行为研究

为了研究异质小麦雄性不育系减数分裂中期Ⅰ与后期Ⅰ的染色体行为及与育性恢复的相关性,以几类异质小麦雄性不育系为母本,用常规品种(系)作为父本与其杂交,调查了杂种F1减数分裂中期Ⅰ单价体频率与后期Ⅰ染色体变异率及自交结实率之间的相关性.结果表明:(1)花粉母细胞减数分裂中期Ⅰ单价体频率与后期Ⅰ染色体变异率呈显著正相关,后期Ⅰ染色体变异率与自交结实率呈负相关,但不显著;(2)相同异质不育系与相同或不同品种杂交时减数分裂中期Ⅰ单价体频率与后期Ⅰ染色体变异率及结实率差异不显著;(3)不同异质不育系与相同或不同品种杂交时减数分裂中期Ⅰ单价体频率与后期Ⅰ染色体变异率差异性较为显著,但减数分裂中期Ⅰ单价体频率与结实率差异性不显著;(4)异质小麦中,异源胞质影响染色体变异,但核基因是调控的关键因素.     

花生种间杂交后代的细胞学观察及其可育性研究

花生原产于南美洲,国外从三十年代就开始研究花生野生资源的利用,到五十年代初才获得了与栽培种杂交的不育三倍体杂种,到七十年代不少国家重视了这项研究,并获得了一些抗病性强、品质优良的种间杂种材料。 国内从近几年开始研究,我们先后对花生种间杂交亲和性及花生种间三倍体杂种染色体加倍技术等进行了报导,同时也获得一些杂种材料和连续与栽培种回交的子代材料,现正在选育中。 花生种间杂交,由于双亲的染色体倍性不同,杂交后产生的三倍体(2n=30)杂种尽管经过人工加倍处理后,F_1代杂种成为可育的异源六倍体(2n=60),     

专论细胞遗传学研究在花生育种中的应用

由10个栽培品种和一个二倍体野生种A.Chacoenoe(Pl276235)杂交产生了三倍体的种间杂种。杂种表现了不同的交叉频率,这证明不同的花生品种的染色体配对能力是不同的,同时也揭示出克服杂交不亲合性并使之成功的可能性。为了进行普通细胞学研究并详细地鉴别外加系和替换系,对花生粗线期20条染色体进行了鉴别,并作了首次的叙述与分类。发现A—染色体是一个相当小的完全异染色质的染色体。 为了填补某些种的种子败育我们知识上的缺口,对根茎区系一些种的胚胎学进行了研究,这些种受精作用进行迟缓和不完全受精。种子败育大概是由于胚乳发育停止和内种皮细胞发育增生等原因所致。种间三倍体杂交呈现了不能受精的无配子生殖所具有的那种胚胎特征。     

Mineral composition of some traditional Mexican teas

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.     

Comparative Assessment of the Efficacy of Various Nitrogen Fertilizers

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.     

Redox Status and Neuro Inflammation Indexes in Cerebellum and Motor Cortex of Wistar Rats Supplemented with Natural Sources of Omega-3 Fatty Acids and Astaxanthin: Fish Oil,Krill Oil,and Algal Biomass

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.     

Potential of dry fractionation of wheat bran for the development of food ingredients,part II: Electrostatic separation of particles

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.     

Pharmacokinetics of Marine-Derived Drugs

Marine organisms represent an excellent source of innovative compounds that have the potential for the development of new drugs. The pharmacokinetics of marine drugs has attracted increasing interest in recent decades due to its effective and potential contribution to the selection of rational dosage recommendations and the optimal use of the therapeutic arsenal. In general, pharmacokinetics studies how drugs change after administration via the processes of absorption, distribution, metabolism, and excretion (ADME). This review provides a summary of the pharmacokinetics studies of marine-derived active compounds, with a particular focus on their ADME. The pharmacokinetics of compounds derived from algae, crustaceans, sea cucumber, fungus, sea urchins, sponges, mollusks, tunicate, and bryozoan is discussed, and the pharmacokinetics data in human experiments are analyzed. In-depth characterization using pharmacokinetics is useful for obtaining information for understanding the molecular basis of pharmacological activity, for correct doses and treatment schemes selection, and for more effective drug application. Thus, an increase in pharmacokinetic research on marine-derived compounds is expected in the near future.     

Novel food and non-food uses for sorghum and millets

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.     

<Emphasis Type="Italic">Pulque</Emphasis>, An Alcoholic Drink from Rural Mexico,Contains Phytase. Its <Emphasis Type="Italic">in vitro</Emphasis> Effects on Corn Tortilla

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.     

La pourriture fongique des tubercules de pomme de terre en atmosphère contrôlée

Résumé Fusarium culmorum et, dans une moindre mesure,F. avenaceum, F. sambucinum, Colletotrichum coccodes etCylindrocarpon sp. ont été isolés de tubercules entreposés en atmosphère contr?lée (AC) et atteints de pourriture grave. Des expériences d'inoculation de tubercules avec 10 espèces ou variétés fongiques et conservation en AC à 8 et 10°C ont montré que: 1) les champignons non pathogènes en atmosphère normale (ex.:Cylindrocarpon sp.) le devenaient en AC, 2) ceux qui étaient faiblement pathogènes en atmosphère normale étaient nettement plus virulents en AC (ex.:F. culmorum), 3) les espèces ou variétés virulentes en conditions d'air normales (Fusarium sulphureum etPhoma exigua var.foveata) ne provoquaient pas de pourriture plus grave en AC et leur activité pouvait même être légérement freinée.

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Summary The extensive rotting of tubers which occurred during storage trials in controlled atmospheres has led to a mycological and pathological study of the rots. The most frequently isolated species wasFusarium culmorum althoughF. avenaceum, F. Sambucinum, Coletotrichum coccodes and aCylindrocarpon sp. were also present. Tubers of cvs Bintje and Ulla were inoculated with 19 isolates of 10 fungal species or varieties associated with rotting of stored tubers (Table 1). The tubers were incubated at 8 or 10°C in normal or controlled (2% O₂:1% CO₂, 2% O₂:6% CO₂, 2% O₂:12% CO₂, 6% O₂:6% CO₂) atmospheres and the extent of rotting was determined a month later (Tables 2 and 3 and Fig. 2). Species which were weakly virulent in a normal atmosphere (variousFusarium spp. andPhoma exigua var.exigua) were clearly more aggressive in the controlled atmosphere and this was especially evident in the case ofF. culmorum. Species ot pathogenic in a normal atmosphere under experimental conditions (Colletotrichum coccodes, Cylindrocarpon sp.,Phoma eupyrena) caused rotting in the controlled atmosphere. The two species which were virulent in a normal atmosphere (F. sulphureum andP. exigua var.foveata) were also virulent in the controlled atmosphere and in some cases the extent of rotting was even less. As a general rule, rotting caused by weakly virulent fungi was greater in both cultivars in the controlled than in a normal atmosphere.

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Zusammenfassung Eine starke F?ulnis von in Kontrotrollierter Atmosph?re gelagerten Kartoffelknollen veranlasste eine mykologische und pathologische Untersuchung. Der am h?ufigsten isolierte Pilz warFusarium culmorum. F. avenaceum, F. sambucinum, Colletotrichum coccodes undCylindrocarpon sp. wurden ebenfalls bestimmt. Neunzehn St?mme von 10 Pilzsorten oder-Arten welche bei Lagerf?ulnis vorkommen (Tab. 1) wurden auf Knollen der Sorten Bintje und Ulla inokuliert. Die Lagerung wurde bei 8 oder 10°C under Normalbedingungen oder kontrollierter Atmosph?re durchgeführt (2% O₂:1% CO₂, 2% O₂:6% CO₂, 2% O₂:12% CO₂, 6% O₂:6% CO₂). Der F?ulnisgrad (Abb. 1) wurde nach einem Monat bonitiert. Die Ergebnisse sind in den Tabellen 2 und 3 dargestellt und in der Abb. 2 illustriert. Unter in Normalbedingungen nur schwach virulente Arten (verschiedeneFusarien undPhoma exigua var. exigua) waren deutlich aktiver in kontrollierter Atmosph?re. Dies was besonders der Fall fürF. culmorum. Pilze, die im Versuch unter Normalbedingungen nicht pathogen waren (Colletotrichum coccodes, Cylindrocarpon sp., Phoma eupyrena), haben unter kontrollierter Atmosph?re Sch?den verursacht. Hingegen werden die beiden unter Normalbedingungen sehr pathogenen Arten (F. sulphureum undP., exigua var.foveata), durch kontrollierte Atmosph?re wenig beeinflusst. Es wurde sogar in einigen F?llen eine gewisse Verringerung des F?ulnisbefalls beobachtet. Ganz allgemein haben die getesteten kontrollierten Bedingungen die Entwicklung der Pilzf?ulnis an beiden Kartoffelsorten gef?rdert, speziell durch Pilzarten, welche unter Normal-bedingungen wenig Sch?den verursachen.

     

Cytoplasmic substitution inSolanum. II. Tuber characteristics of reciprocal backcross progeny

Summary Recurrent backcrosses (BC) were used to introduce nuclear factors ofS. tuberosum L. ssp.tuberosum into the cytoplasm of Andean potatoesS. tuberosum ssp.andigena (Juz. and Buk.) Hawkes andS. phureja Juz. and Buk. Each generation BC was produced in reciprocal directions to test the effect of cytoplasmic substitution on yield. This report analyses tuber number, tuber weight, and tuber length of BC₂ and BC₃ substitution into ssp.andigena cytoplasm and BC₂ and BC₂ substitutions intoS. phureja cytoplasm. Direction of cross had no consistent significant effect on yield components of ssp.andigena substitution lines. InS. phureja reciprocal progenies direction of cross was responsible for significant differences of some reciprocal sets. When there were significant differences the higher yield usually occurred when ssp.tuberosum was the pistillate parent, but in some progenies when ssp.tuberosum was the pistillate parent the yield was significantly lower than in the reciprocals. It is suggested that differences between reciprocals resulted from chromosomally encoded gene action, resulting from maternal and/or paternal effects, rather than cytoplasmic factors. Authorized for publication as paper No. 7494 in the Journal Series of The Pennsylvania Agriculture Experiment Station.