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应用0.32%印楝素乳油防治小菜蛾的田间药效试验,试验结果表明:0.52%印楝素乳油对小菜蛾具有良好防效,施药后3天的防效达81%～92%,药后7天的防效分别达92%～100%,而且对作物无药害. 相似文献
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本试验采用西藏著名野生花卉蓝玉簪龙胆茎段为组织培养材料,通过多次试验后确定：蓝玉簪龙胆的启动培养中适宜的培养基为;ＭＳ＋ＮＡＡ０．５（ｍｇ／１,激素单位下同）＋ＢＡ０．５－１．０,每茎段平均分化形成４．２个芽;诱导愈伤组织的适宜培养基为ＭＳ＋ＢＡ０．５＋ＮＡＡ０．５－１．０; 相似文献
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一氧化氮(NO)是一种在植物次生代谢中起着重要调控作用的信号分子.我们以硝普钠(SNP)作为NO供体处理新疆紫草愈伤组织.实验表明,SNP处理的新疆紫草红色愈伤组织中AePGT,AeGPPS,AeC4H与Ae4CL的表达量比未处理组明显提高.对萘醌类代谢物谱的分析显示,SNP处理也引起新疆紫草愈伤组织中紫草素及其衍生物含量的增加.上述结果表明,SNP处理产生的NO,可能通过上调紫草素及其衍生物合成相关的基因表达,促进紫草素及其衍生物的合成. 相似文献
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本文主要研究不同2,4－D浓度和培养条件对愈伤组织诱导的影响,结果表明：诱导愈伤组织最好的配比为 MS培养＋6－BA：1．0mg/L＋NAA：0．1mg/L＋2,4－D：1．0mg/L. 相似文献
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电子预印：一种出版新思路 总被引：3，自引：1，他引：2
汪谋岳 《中国科技期刊研究》2000,11(6):391-393
电子预印是一种新兴的电子出版方式,较传统出版方式有许多优点,但也存在一些实际问题。介绍了电子预印的涵义、发展现状、利弊及给我们国内编辑出版界的启示。建议有条件的单位或组织做一些尝试,至少应对电子预印以应有的关注。 相似文献
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灌溉水矿化度对玛纳斯流域棉花生长影响的试验研究 总被引：4，自引：0，他引：4
合理利用咸水资源对缓解干旱区绿洲农业用水矛盾有重要意义。本文于2010年和2011年在石河子大学节水灌溉试验站研究了矿化度为0.87、2、3、4、6、8g/L的咸水对土壤水盐动态和棉花生长及产量的影响。结果表明,咸水灌溉导致土壤剖面持续积盐,棉花叶面积指数减小,干物质积累减少、产量下降;灌溉水矿化度每提高1g/L,产量降低约391kg/hm2;土壤根系层(0～60cm)可溶性盐浓度每升高1g/L,产量降低约861kg/hm2。在灌溉水矿化度2g/L情况下,100cm土层盐分最大累积率2010年为113%,2011年为26%,呈下降趋势,棉花生长、干物质积累及产量受影响较小,可作为该区咸水利用调控参考阈值,指导农业生产。 相似文献
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BackgroundIn order to produce an effective callus in Echinacea purpurea L.; determination of the explant type and growth regulators that best respond to callus induction and the optimization of the culture conditions to increase the amount of caffeic acid derivatives (CADs) in the obtained callus. CADs contents of callus cultures of E. purpurea were evaluated by establishing an effective callus induction system in vitro.ResultsVarious medium containing different growth regulators were tested using leaf, petiole, cotyledon and root as the explants. The best callus development was achieved in MS medium with 1.0 mg l−1 2,4-D + 2.0 mg l−1 BAP in leaf, 1.0 mg l−1 NAA + 0.5 mg l−1 TDZ in petiole, 2.0 mg l−1 NAA + 1.0 mg l−1 TDZ in cotyledon and 0.5 mg l−1 NAA + 0.5 mg l−1 BAP in roots. Upon optimisation of callus growth, each type of explant was cultured for 4, 6, 8 and 10 weeks in medium for the analyses of caftaric acid, chlorogenic acid, caffeic acid and chicoric acid contents. The highest amounts of caftaric acid (4.11 mg/g) and chicoric acid (57.89 mg/g) were found from petiole explants and chlorogenic acid (8.83 mg/g) from root explants at the end of the 10-week culture time.ConclusionsAs a result of the present study, the production of caffeic acid derivatives was performed by providing the optimization of E. purpurea L. callus cultures. Effective and repeatable protocols established in this study may offer help for further studies investigating the production of caffeic acid derivatives in vitro.How to cite: Tanur Erkoyuncu M, Yorgancilar M. Optimization of callus cultures at Echinacea purpurea L. for the amount of caffeic acid derivatives. Electron J Biotechnol 2021;51. https://doi.org/10.1016/j.ejbt.2021.02.003. 相似文献
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BackgroundThis research is intended to determine suitable types and concentrations of plant growth regulators (PGRs) to induce callus on stem and leaf sections of 4 species of the genus Garcinia, namely, Garcinia mangostana, Garcinia schomburgkiana, Garcinia cowa, and Garcinia celebica. The base medium was MS medium containing 30 g l-1 sucrose, 0.5 g l-1 polyvinylpyrrolidone (PVP), and 7 g l-1 agar, and for the different treatments, PGRs were added to the medium as follows: thidiazuron (TDZ) at concentrations of 0, 0.1, 0.5, 1, and 2 mg l-1; 6-(3-hydroxybenzylamino) purine (meta-topolin) at concentrations of 0, 0.5, 2.5, and 5 mg l-1; 4-amino-3,5,6-trichloro-2-pyridinecarboxylic acid (picloram) at concentrations of 0, 0.5, 2.5, and 5 mg l-1; and 2,4-dichlorophenoxyacetic acid (2,4-D) at concentrations of 0, 0.5, 1, 2, and 4 mg l-1. The occurrence of callus was observed after 4 weeks.ResultsA maximum of 100% and 93% of G. mangostana leaf explants formed callus in the 0.5 mg l-1 and 1 mg l-1 TDZ treatments, respectively, while 100% of G. schomburgkiana stem explants formed callus in the 1 mg l-1 TDZ treatment and 89% of G. schomburgkiana leaf explants formed callus in the 0.5 mg l-1 picloram treatment. The highest callus induction rate for G. cowa was 62% in the 1 mg l-1 TDZ treatment and for G. celebica was 56% in the 0.5 mg l-1·mT-1 treatment.ConclusionsFor all 4 species, the greatest amount of large nodular callus was observed in the TDZ treatments. White, friable callus was observed on most of the 2,4-D and picloram treatment groups. Most meta-topolin treatments resulted in minimal callus formation.How to cite: Suwanseree V, Phansiri S, Yapwattanaphun C. A comparison of callus induction in 4 Garcinia species. Electron J Biotechnol 2019;40. https://doi.org/10.1016/j.ejbt.2019.04.006 相似文献
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不同盐分含量的海冰水灌溉对棉花产量和品质的影响 总被引：2，自引：0，他引：2
采用不同盐分含量的海冰水进行棉花灌溉试验,结果表明:①经过1年3次灌溉和降雨淋洗作用,海冰水盐分含量为1g/L、3g/L和5g/L的灌溉处理,土壤均表现为明显的脱盐效果,在0～20cm表层土壤脱盐率随海冰水盐分含量升高而降低,脱盐率最高为1g/L处理,达到57.22%,分别高于3g/L和5g/L处理3.28%和18.34%;而盐分含量为7g/L和9g/L的灌溉处理0～80cm土壤各层次表现为积盐,以60～80cm积盐最为严重。②各处理以1g/L和3g/L海冰水灌溉棉花果枝数、单颗棉桃重和产量最高,随灌溉水盐分含量增加产量呈递减的趋势,9g/L海冰水灌溉3次的处理与无灌溉相比出现显著减产,减产率为28.48%;7g/L和9g/L的2个处理,棉花整齐度指数和断裂比强度都有降低趋势,但各处理间棉纤维品质差异不显著。综合考虑海冰水长期灌溉效应及海冰脱盐技术,建议采用3g/L海冰水进行棉田灌溉,并要注意配合必要的灌溉和排水措施。 相似文献
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针对水源水中硝酸盐氮（NO3-N）,采用批实验开展了生物脱氮研究,考察了碳源种类对生物脱氮的影响,并考察了豌豆秆作为固体碳源时颗粒铁、碳源用量、N03-N初始浓度和水温等因素对生物脱氮的影响。实验结果表明：甲醇、豌豆秆和木屑完全脱氮的时间分别为2天、7天和30天;三种碳源均会引起亚硝酸盐氮的短暂积累,但最大积累量出现的时间不同;在模拟水中富含溶解氧时,含有颗粒铁的反应瓶在2天内可以实现完全脱氮,而对照瓶仅去除45．7％的N03-N;第2天时,1g豌豆秆时N03-N去除率为47．8名,3g时去除率为71．9％,而5g时去除率为99．6％;低浓度和高浓度时的豌豆秆生物脱氮速率分别是11．28mg／L／d和10．91mg／L／d;15。C时的豌豆秆生物脱氮速率约为33。c时的1／3,27cc时的脱氮速率约为33oc时的3／4。碳源种类、颗粒铁、豌豆秆用量和水温显著影响豌豆秆生物脱氮效果;在既定浓度范围内（5．65mg／L-21．92mg／L）,N03-N初始浓度对生物脱氮基本无影响。 相似文献
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《Electronic Journal of Biotechnology》2014,17(3):107-113
BackgroundThe properties of natural pigments, such as antioxidants, functional, medical, and nutraceutical, have demonstrated the advantages of these natural compounds over synthetic ones. Some products are accepted only when they are pigmented with natural, food-quality colorants: for example poultry products (manly marigold flower extracts). Carotenoids such as β-carotene, β-criptoxanthin and lutein are very attractive as natural food colorants due to their antioxidant and pro-vitamin activities which provide additional value to the target products. Marigold (Tagetes erecta) is an Asteraceous ornamental plant native to Mexico, and it is also important as a carotenoid source for industrial and medicinal purposes but nowadays its production is destined mainly for ornamental purposes.ResultsFriable callus of T. erecta yellow flower (YF) and white flower (WF) varieties was induced from leaf explants on Murashige and Skoog (MS) medium supplemented with 9.0 μM 4-dichlorophenoxyacetic acid (2,4-D) and 8.8 μM benzyladenine (BA). Calluses developed from both varieties were different in pigmentation. Extract characterization from callus cultures was carried out by high-performance liquid chromatography (HPLC). This analytical process detected several carotenoids; the main pigments in extracts from YF callus were lutein and zeaxanthin, whereas in the extracts of the WF callus the main pigments were lutein, zeaxanthin, β-cryptoxanthin and β-carotene. Callus cultures of T. erecta accumulated pigments even after several rounds of subculture.ConclusionsWF callus appeared to be a suitable candidate as a source of different carotenoids, and tested varieties could represent an alternative for further studies about in vitro pigment production. 相似文献
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P. Ratnakar P. Suryanarayana Murthy 《Indian journal of clinical biochemistry : IJCB》1996,11(1):37-41
Water extract of garlic (Allium sativum) inhibited the growth ofMycobacterium tuberculosis H37Rv andM. tuberculosis TRC-C1193 susceptible and resistant to isoniazid respectively. The minimum inhibitory concentration (MIC) was slightly above 80 but less than 160 μg/ml and slightly above 100 but less than 200 μg/ml for the susceptible and resistant strains respectively. Gel filtration in Sephadex G-100 columns showed that two protein fractions (43 & 38 kD) possessed antitubercular activity with much lower MICs of 20–40 μg/ml and 30–60 μg/ml for susceptible strain. Water extract, when added to actively growingM. tuberculosis in their mid log phase prevented their further growth. The water extract of garlic inhibited the incorporation of14C glycine into whole cells by 81% in 6 hrs. indicating that the primary mechanism of action is by inhibition of protein synthesis. 相似文献
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“一带一路”省市城市基础设施利用效率分析——基于DEA及Malmquist指数模型 总被引：1，自引：0，他引：1
以一带一路17个省市2005~2014年的面板数据为基础,采用DEA及Malmquist指数模型将一带一路分为东南、东北、西南和西北四大板块,分析发现,东南地区综合效率最高,但TFP增长一般,主要为纯技术效率增长较慢;东北地区综合效率偏低,主要由于纯技术效率和增长率偏低;西南地区综合效率偏低的原因为纯技术效率偏低,但其增长率保持较高水平,技术进步慢是导致TFP增长缓慢的原因;西北地区由于规模效率过低导致综合效率偏低,且规模效率增长速度不够,加上技术进步速度偏低,TFP进步较慢。 相似文献