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191.
植物提取物对南方根结线虫的控制作用 总被引:16,自引:0,他引:16
采用浸渍生测法测定了采自广东、新疆、湖南的15科28种植物提取物对南方根结线虫Meloidogyne incognita的毒杀活性.结果表明:骆驼蓬Peganum harmala、黄文江鱼藤Derris elliptica和火殃勒Euphorbia antiguontm甲醇提取物以1000μg/mL处理后48h,供试2龄线虫校正死亡率分别为86.46%、69.28%和70.84%,处理后72h,校正死亡率分别为98.20%、85.45%和81.90%,呈强杀线虫活性.此外,厚果鸡血藤Millettia pachycarpa、桃花心木Swietenia mahagany等12种植物甲醇提取物亦有较强的杀线虫活性.盆栽试验结果表明:骆驼蓬、黄文江鱼藤、厚果鸡血藤、桃花心木提取物处理的番茄地上部植株高度分别比对照增长163.35%、90.61%、155.99%和178.08%,地上部鲜质量分别增长191.37%、130.25%、79,25%和124.35%.骆驼蓬、黄文江鱼藤、桃花心木、火殃勒提取物处理后根长分别增长140.57%、93.40%、135.85%和107.55%,均显著优于或相当于对照药剂阿维菌素(30μg/mL,即6%乳油2000倍)处理增长率98.11%.黄文江鱼藤提取物处理后根结数2.33个/株,病级最低(1.00),显著低于印楝素2.5μg/mL处理.骆驼蓬、黄文江鱼藤、桃花心木、火殃勒对盆栽番茄南方根结线虫病控制效果明显. 相似文献
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为了深入理解斑地锦对入侵地作物的危害及其入侵机制,用蒸馏水浸提斑地锦茎叶内地有效成分,以番茄、辣椒、苋菜和荆芥为受体,利用培养皿滤纸法研究斑地锦浸提液对种子萌发和幼苗生长的影响.结果表明,斑地锦浸提液可降低四种蔬菜种子的发芽速率,抑制番茄、辣椒和荆芥的发芽率,并且这种抑制作用随处理浓度的提高而加强,而对苋菜种子的发芽率无显著影响;0.4 g/ml的斑地锦浸提液强烈抑制了四种蔬菜根的生长,却不同程度地促进了辣椒、荆芥和苋菜茎的生长,对根/茎比的影响与对种子发芽率的影响类似. 相似文献
194.
文章在广东省九连山林场开展碳汇林套种五指毛桃 Ficus hirta 的林下经济模式研究,利用双
因素方差分析法,从坡位、密度以及坡位和密度的交互作用 3 个因素来研究其对地径、苗高、冠幅、根
长和根重的影响。结果表明:不同坡位对五指毛桃地径、冠幅、根长和根重产生显著影响;不同密度对
五指毛桃地径、冠幅、根长和根重产生显著影响;不同坡位与密度的交互作用对五指毛桃的地径、苗
高、冠幅、根长和根重均产生极显著影响;五指毛桃地径和苗高长势最佳的是位于中坡的密度为 6 255 和
3 120 株 /hm2 的植物样本;冠幅长势最佳的是位于上坡和中坡的密度为 3 120 株 /hm2 的植物样本;地下
部分最有优势的是为位于上坡的密度为 2 760 株 /hm2 的植物样本。 相似文献
195.
Chemical investigation of the Hainan soft coral Sinularia hirta resulted in the isolation and identification of a library of sixteen structurally diverse terpenoids, including a dinorditerpenoid with an uncommon 17,19-dinorxeniaphyllane skeleton, namely sinuhirtone A (7), six new xeniaphyllane-type diterpenoids (1–6), one new norxeniaphyllanoid (8), two new norcaryophyllene-type sesquiterpenoids (9 and 10), together with six known related compounds (11–16). Compounds 1–3 are three new furanone-containing xeniaphyllane-type diterpenoids. The structures of the new compounds, including their absolute configurations, were determined by extensive spectroscopic analysis and a series of quantum chemical calculations, including quantum mechanical-nuclear magnetic resonance (QM–NMR), time-dependent density functional theory–electronic circular dichroism (TDDFT–ECD), and optical rotatory dispersion (ORD) methods. A plausible biosynthetic connection between new compounds 1–9 was also proposed. New compounds 2–4, 7, and 8 were evaluated for in vitro cytotoxicity against four cancer cell lines. 相似文献
196.
一品红组培苗移栽期叶片生理与解剖变化 总被引:4,自引:0,他引:4
一品红(Euphorbia pulcherrima),别名象牙红、老来娇、圣诞花、猩猩木,为大戟科大戟属的重要花卉,世界各地广为栽培,为圣诞节、元旦、春节的优良装饰花卉。目前我国市场的矮化一品红主要由进口种苗培育而成,国内利用组织培养技术培育矮化一品红种苗已有不少成功的报道(钟士传等,1999;蒋小满等,2002),但一品红试管苗移栽时叶片较易萎蔫、成活率较低,为其种苗生产带来了困难。本试验研究一品红试管苗在移栽驯化过程中叶片蒸腾、光合特性及解剖结构的变化,探索提高其移栽成活率的方法,以便为矮化一品红种苗产业化提供技术支持。1材料与方法1·… 相似文献
197.
The hydrosoluble fraction of Euphorbia royleana latex (AER), administered by gavage at doses of 50-200 mg/kg, showed dose-dependent anti-inflammatory and anti-arthritic effects in different acute and chronic test models in rats and mice. It reduced the exudate volume and the migration of leukocytes and showed a poor inhibitory effect on the granuloma formation induced by cotton pellets, while it had a low ulcerogenic score. The oral LD(50) was more than 1500 mg/kg in both rats and mice. 相似文献
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Summary Protocols for plant regeneration from cotyledon explant and anther cultures of Sinapis alba have been developed for creating doubled-haploids and somaclonal variation. Among the several cultivars tested in this study, only Arda responded well to in vitro plant regeneration both from anther-as well as cotyledoncultures. Multiple shoot formation in cotyledon explants, which always followed a brief callusing phase, was found to be the best on MS medium with ZEA (1.0mg/l) and NAA (0.1mg/l). Regeneration frequency declined sharply in the absence of auxin or presence of other cytokinins and/or auxin. The frequency of shoot regeneration also declined with reduction in the photoperiod to 16h. On MS + BAP (1.0mg/l) + NAA (1.0mg/l) medium, cotyledonary explants showed profuse callusing, which could regenerate shoots on high ZEA + low NAA/IAA medium. However, it declined with progressing time in culture. Anthers, excised from fresh as well as cold pretreated buds, cultured on 10% sucrose containing MS media with different hormonal constitution, developed calli and/or embryos. Initial culture temperature was important with embryogenesis occurring only in anthers cultured at 30°C for 3 weeks. A high temperature (35°C) treatment was lethal for both callus as well as embryo formation. While BAP + NAA and ZEA + NAA/IAA supported embryogenesis, further plant regeneration from anther-or embryo-callus could be achieved in ZEA + NAA/IAA media. Some of the regenerants flowered already in vitro and had small and sterile flowers. Cytological examination of some of the root differentiating calli indicated the presence of haploid as well as diploid cells. Shoots were rooted during prolonged incubation on the same medium or on transfer to MS (reduced)/ B5 + ZEA + NAA media. 相似文献