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1.
用青霉素处理小麦胚乳（无胚半粒种子），发现能诱导α－淀粉酶的合成。青霉素的诱导作用具有浓度效应，当青霉素浓度低于５００ｍｇ／Ｌ（含５００ｍｇ／Ｌ）时，小麦胚乳的α－淀粉酶活性随浓度的增加而提高；用５００ｍｇ／Ｌ青霉素处理后，酶活性提高４６．７％～７３．５％。超过５００ｍｇ／Ｌ时，酶活提高有所回落，但仍高于对照。另外，在诱导过程中，α－淀粉酶的活性受到Ｃａ＾（２＋）的调节及温度的影响，其中以２５℃为 相似文献
2.
多效唑对延缓龙眼枝叶生长的效应 总被引：2，自引：0，他引：2
用多效唑对龙眼东壁品种的夏梢、秋梢幼茎进行不同浓度（５００－３００μｇ／ｍｌ）喷洒，结果表明：１．枝梢节间长度缩短，仅为对照的１／２－１／５，且随多效唑浓度的增加，其效果更显；２．低浓度多效唑喷洒可增大叶面积，高浓度喷洒则相反。各处理叶片厚度均显增加；３．处理后的第１０天和第４０天测定其叶绿素含量比对照分别提高３８．０４％和３０．１９％，且光合速率加快，１０００μｇ／ｍｌ处理的为对照的１．７倍 相似文献
3.
１材料与方法１．１供试品种及药剂供试品种为感病糯稻，试验药剂为３０％稻病宁ＷＰ，４０％富士一号ＥＣ。１．２试验地基本情况试验地设在农垦水稻所栽培地内，老稻田土壤为轻度沼泽化草甸土，有机质含量为 ３％， ｐＨ值为 ６． ５，栽培密度 ３０ｃｍ×２０ｃｍ。插秧前５天（５月９日）施用了草胺封闭灭草，施肥水平为尿素：２００ｋｇ／ｈｍ２，二铵：１００ｋｇ／ｈｍ２，颗粒钾肥１００ｋｇ／ｈｍ２。由于７月中旬连续大雾，试验地块发病严重。１．３试验处理及方法试验设６个处理，各处理每公顷用药量分别为 ３０％稻病宁 ＷＰ ７… 相似文献
4.
5.
矮化处理低、中、高三个不同密度的夏花生，其株高比对照处理３个相应密度均矮１０ｃｍ左右。结实指数分别提高８．１４％、１０．２％和１８．８１％；饱果指数分别提高２．１４％、６．９３％和１０．３３％。总生物产量的分配，Ｖ／Ｒ率均＜１，经济系数均＞０．５５，经济产量依次提高８．２１％、１４．６４％和２２．７６％。实际荚果产量，矮化处理的以高密度（２２．５万穴／ｈｍ２）最高、中密度（１８．７５万穴／ｈｍ２）次之，分别比低密度（１５万穴／ｈｍ２）增产１５．０４％～１６．８９％和１４．０２％～１４．５４％；对照处理以中密度最高，高密度次之，分别比低密度增产１１．７１％～１２．４０％和５．３４％～７．９１％。矮化处理与密度有显著的连应效果，比对照处理依次增产７．５５％、９．６％和１６．５％。 相似文献
6.
金线莲组织培养与人工栽植研究──Ⅳ.瓶苗移栽与低海拔平地试种 总被引：1，自引：0，他引：1
以福建、广西、台湾金线莲组织培养瓶苗为供试材料，在海拔２０米，６－９月份平均气温２５．５－２８．８℃地区的人工荫棚下，金线莲试种初步获得成功．对人工栽培进行了技系统的试验比较，结果表明：（１）瓶苗素质对移栽成活保存率有很大影响．健化的壮苗自１９９２年１１月种植至１９９３年７月长达８个月成活保存率达９６．６％；（２）广西和台湾金线莲比福建金钱莲适应性略强．前二者９３年７月栽植至９４年３月生育期８个月。历经越夏和秋冬后成活率仍达８７．５、８０．４％；（３）３—１２月份均可人工栽植；（４）用５份蛇木屑＋１份石，３份蛇木屑＋１份腐植土＋１份炭化稻壳为基质，栽植１４个月后保存率达９０％；（５）ＡＢＴＩ、２、３号生根粉对生根都有明显促进作用，以２００ｐｐｍ浸泡３０分为佳；（６）叶片喷施高效稀土液、１／４ＭＳ、ＡＢＴ３号．碧全可分别提高株鲜重１０２．９、７１．３、５９．２、４７．９％；（７）试种点栽植周年的组培植株开花率仅为１．５％；（８）台湾金线莲试种生长１５－１６个月，每株鲜重可达１．１克以上． 相似文献
7.
花生去子叶幼胚的丛生芽诱导和植株再生 总被引：1，自引：0，他引：1
授粉后２５－３０天的花生幼胚，去子叶后，在ＭＳ２（ＭＳ＋ＢＡ１．０ｍｇ／Ｌ＋ＣＨ３００ｍｇ／Ｌ＋ＰＶＰＰ０．３％＋椰计５０ｍｌ／Ｌ＋蔗糖４％＋琼脂０．８％）培养基中，置３００ｌｕｘ弱光和２０℃±１℃条件下，培养２１－２８天，能有效地产生丛生芽；在ＭＳ２中诱导培养后的去子叶幼胚的生长点切去，在改良无激素培养基（ＭＳ１）中培养１４天，转入ＭＳ３（ＭＳ＋ＢＡ６．０ｍｇ／Ｌ＋ＮＡＡ０．４ｍｌ／Ｌ＋Ｄ－生物素０．１ｍｇ／Ｌ＋ＣＨ３００ｍｇ／Ｌ＋酵母浸出物２００ｍｇ／Ｌ＋椰计５０ｍ／Ｌ＋ＰＶＰＰ０．３％＋蔗糖２．５％＋琼脂０．８％）培养基，置２５℃±１℃，３５００ｌｕｘ光照条件下培养２１－２８天，８０％的外植体分化出丛生芽，继而长成无根带叶小苗．．平均每外植体产生８．１个丛生芽，最多可达４０个．诱根后小苗移植田间８０％植株成活并开花结实。品种（系）间差异不显著。 相似文献
8.
生产上“丁草胺＋稻无草”对稻田杂草混生群落防除效果较好，但由于丁草股对河蟹杀伤力较大，不宜在养蟹稻田内施用，所以我们进行“艾割＋稻无草”除草试验。1材料与方法1．1试材：10％艾割乳油（美国氰胺公司注册）；10％稻无草可湿性粉剂（江苏如东农药厂出品）；3－4期幼蟹和150—200只／500g扣蟹。1．2试验设计：处理1（稻田内）：艾割26．7ml／亩（合0．08ppm）＋稻无草20g／亩；处理2（稻田内）：艾割53．4ml／亩（合0．16Ppm）＋稻无草20g／亩；处理3（盆内）：用药同处理1；处理4（盆内）：用药同处理2。以上处理二次重复；处理5… 相似文献
9.
本文报道采用ＭＲ－０３保鲜剂处理的“台农４号”菠萝，置于常温（２５．２—２８．６℃）下贮藏２０天，好果率达９６．７％．贮藏３０天，好果率达７３．３％，系最高．经生理生化分析，ＭＲ－０３处理的果实在贮藏过程中，其呼吸强度和细胞膜渗透率均维持在较低水平，贮藏结束分别为１３．２４ｍｇＣＯ＿２·Ｋｇ￣（－１）ｈ￣（－１）和４８．９％，系最低．果实中总糖、总酸、可溶性固形物和Ｖｃ分别为１１．９％、０．５０％、１２．３％和６．０４ｍｇ／１００ｇ，与贮前相比，下降幅度最小．还原糖为７．１％，与贮前相比，增加幅度最大．同时，通过对果实的感官品评，其结果为：果实失水较少，果眼饱满，果皮鲜黄，果肉爽脆．甜酸适宜，且具有浓郁的菠萝香味． 相似文献
10.
萌发条件对水稻双苗率的影响 总被引：1，自引：0，他引：1
通过对双－３、双－１３、陆５２和阿里希斯尼４个多胚水稻品系的研究，结果表明多胚水稻的双苗（多苗）性状表达受萌发条件的影响：１．种子去壳后浸种催芽较未去壳浸种催芽的双苗率平均提高２．７％，最高为３．８％。在组织培养条件下萌发，其双苗率的提高更明显，平均为４．４％，最高为７．４％（双苗率由４１％提高到４８．４％）；２．在接种前对种子不同温度的预处理研究表明，温度对双苗率也有较大的影响：二个粳稻品种和籼稻品种双－１３的最适温度为５０℃；籼稻品种双－３的最适温度为３０℃，在此温度预处理后，最高双苗率由４１．０％提高到７５．０％。 相似文献
11.
12.
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
13.
《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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15.
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
16.
Alexander N. Shikov Elena V. Flisyuk Ekaterina D. Obluchinskaya Olga N. Pozharitskaya 《Marine drugs》2020,18(11)
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. 相似文献
17.
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
18.
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.
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.
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.相似文献
19.
Alejandro Carlos Tozzini María Fernanda Ceriani María Verónica Saladrigas H. Esteban Hopp 《Potato Research》1991,34(3):317-324
Summary Clones derived from thirty-one different accessions (nineteen of Argentine origin) belonging to eightSolanum species were screened for resistance to infection by potato virus X strain cp (PVX cp) by mechanical inoculation of plantlets
that had been micropropagated in vitro. Estimates of PVX multiplication obtained by enzyme linked immunosorbent assay and
slot blot nucleic acid hybridization allowed the identification of resistant clones derived from five accessions belonging
toS. commersonii S. oplocense, S. sparsipilum andS. tuberosum andigena. Resistant genotypes supported PVX concentrations 5 to 15 times smaller than did the susceptible control cultivar Spunta.
Graft inoculation test confirmed the presence of extreme resistance similar to that conferred by the ‘immunity’ gene X1 (also called RXact). 相似文献
20.
Alejandro M. S. Mayer Abimael D. Rodríguez Orazio Taglialatela-Scafati Nobuhiro Fusetani 《Marine drugs》2013,11(7):2510-2573
The peer-reviewed marine pharmacology literature from 2009 to 2011 is presented in this review, following the format used in the 1998–2008 reviews of this series. The pharmacology of structurally-characterized compounds isolated from marine animals, algae, fungi and bacteria is discussed in a comprehensive manner. Antibacterial, antifungal, antiprotozoal, antituberculosis, and antiviral pharmacological activities were reported for 102 marine natural products. Additionally, 60 marine compounds were observed to affect the immune and nervous system as well as possess antidiabetic and anti-inflammatory effects. Finally, 68 marine metabolites were shown to interact with a variety of receptors and molecular targets, and thus will probably contribute to multiple pharmacological classes upon further mechanism of action studies. Marine pharmacology during 2009–2011 remained a global enterprise, with researchers from 35 countries, and the United States, contributing to the preclinical pharmacology of 262 marine compounds which are part of the preclinical pharmaceutical pipeline. Continued pharmacological research with marine natural products will contribute to enhance the marine pharmaceutical clinical pipeline, which in 2013 consisted of 17 marine natural products, analogs or derivatives targeting a limited number of disease categories. 相似文献