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61.
N. W. SOTHERTON 《Ecological Entomology》1982,7(2):197-206
Abstract. 1. Observations were made on the biology of Gastrophysu polygoni (L.) (Coleoptera: Chrysomelidae) in cereal fields in southern England in 1977, 1978 and 1979. Adults of the overwintering generation emerged in late April/ May and there were usually two generations during the spring and summer months. In 1979 there was some evidence for at least a partial third generation.
2. In the field, the oviposition period was 44 days in the first generation and c . 25 days in the second. Fecundity varied from 586 to 1028 eggs per female and was higher in the first than in the second generation in both 1977 and 1979; in 1978 the reverse was true.
3. Every year there were Iarge losses in the numbers within a generation. However, only one parasite was bred from the developmental stages and a pathogen attacking the larvae was found only in 1977.
4. In some fields and in some years, harvesting and straw burning operations were carried out when eggs were present on the plants. Harvesting did not result in a significant reduction in the numbers of eggs. Burning reduced the numbers of egg batches. The effect was most severe when the straw was spread over the field prior to burning.
5. In the field, significantly more eggs were laid on plants of Polygonum aviculare than on P.convolvulus . In the laboratory, larval survival was higher and duration of development shorter on these two species than on other Polygonaceae found on the farm. 相似文献
2. In the field, the oviposition period was 44 days in the first generation and c . 25 days in the second. Fecundity varied from 586 to 1028 eggs per female and was higher in the first than in the second generation in both 1977 and 1979; in 1978 the reverse was true.
3. Every year there were Iarge losses in the numbers within a generation. However, only one parasite was bred from the developmental stages and a pathogen attacking the larvae was found only in 1977.
4. In some fields and in some years, harvesting and straw burning operations were carried out when eggs were present on the plants. Harvesting did not result in a significant reduction in the numbers of eggs. Burning reduced the numbers of egg batches. The effect was most severe when the straw was spread over the field prior to burning.
5. In the field, significantly more eggs were laid on plants of Polygonum aviculare than on P.convolvulus . In the laboratory, larval survival was higher and duration of development shorter on these two species than on other Polygonaceae found on the farm. 相似文献
62.
以3% NaHCO3溶液胁迫处理48 h的西伯利亚蓼为试材,利用RACE技术,从其茎部组织克隆了脱水应答蛋白RD22的全长cDNA序列。测序后的结果分析表明,该cDNA序列全长为1 302 bp,5′非翻译区为59 bp,3′非翻译区为25 bp,开放读码框为1 218 bp,编码405个氨基酸。在氨基酸序列的C端含有一个比较保守的BURP结构域,N端含有5个重复序列THV-VGKGGV-V。信号肽检测证明该蛋白为分泌性蛋白,前21个氨基酸区域为信号肽结构。其推演的氨基酸序列与葡萄的同源性最高,达到60%。该基因已在GenBank上注册,基因序列登录号为DQ836050。 相似文献
63.
The aphid genus Blackmania gen. nov. is described. In the genus, B. eastopi sp. nov. associated with Polygonum equisetiforme (Polygonaceae) from Israel and Cyprus is described and illustrated. Morphologically, the new genus is similar to the genus Acaudella in respect to the lack of a cauda. Acaudella puchovi, associated with Atraphaxis caucasica (=A. buxifolia) and A. spinosa (Polygonaceae) from Uzbekistan and Israel, is re‐described and the apterous viviparous female is figured for the first time. The lectotype and paralectotypes of A. puchovi are also designated. An identification key to known species of the tribe Macrosiphini without cauda is provided. The morphological separation of B. eastopi gen. nov., sp. nov. from A. puchovi is visualized using principal component analysis. 相似文献
64.
许崇梅;曲畅游;于文光;张学杰;李法曾 《武汉植物学研究》2009,27(3):262-265
杠板归(Polygonum perfoliatum L.)的系统位置一直存在争议,文中以塔黄为外类群,采用最大简约法对杠板归及其近缘类群的trnL-F序列进行了系统发育分析,结果表明:(1)杠板归和刺蓼为姊妹群,自展分析的支持率为99%,分子证据支持杠板归归人刺蓼组,而没有必要单立组或属。(2)刺蓼组、春蓼组和头状蓼组植物聚在一起,自展支持率为100%,说明它们之间有很近的亲缘关系。 相似文献
65.
Yuping Wang Wenliang He Huiying Huang Lizhe An Di Wang Feng Zhang 《Acta Physiologiae Plantarum》2009,31(4):839-848
Mountain environmental stresses result in increased formation of hydrogen peroxide (H2O2) and accumulation of malondialdehyde (MDA) in leaves of Polygonum viviparum. The activities of several antioxidative system enzymes such as superoxide dismutase (SOD, EC 1.15.1.1), catalase (CAT, EC
1.11.1.6), peroxidase (POD, EC 1.11.1.7), glutathione reductase (GR, EC 1.6.4.2), dehydroascorbate reductase (DHAR, EC 1.8.5.1)
and the contents of several non-enzymatic antioxidants such as reduced form of ascorbate (ASC), dehydroascorbate (DHA), reduced
glutathione (GSH), and oxidized glutathione (GSSG) were investigated in leaves of P. viviparum, which were collected from three altitudes (2,200, 3,200, and 3,900 m) of Tianshan Mountain in China. The activities of these
four antioxidative enzymes were accompanied by increases of H2O2 levels from 2,200 to 3,200 m. However, the activities of CAT and POD were decreased, whereas the activities of SOD and GR
continually increased at 3,900 m. Analyses of isoforms of SOD, CAT, POD, and GR showed that the leaves of P. viviparum exposed different altitude conditions are capable of differentially altering the intensity. Additionally, two new isoforms
of SOD were detected at 3900 m. A continual increase in the ASC, ASC to DHA ratio, GSH and GSH/[GSH + GSSG] ratio, and the
activity of DHAR were observed in leaves of P. viviparum with the elevation of altitude. These results suggest that the higher contents of ASC, GSH as well as an increase in reduced
redox state may be essential to antioxidation processes in the leaves of P. viviparum, whereas antioxidant enzymes system is a cofactor in the processes. 相似文献
66.
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68.
目的:对药用植物东方蓼的染色体数目、核型、体积等进行了研究。方法:采用常规制片方法,结合显微摄影对染色体的数目进行统计分析。结果:东方蓼体细胞染色体数目2n=22,相对长度组成2n=22=10M2+12M1;核型公式为K(2n)=2X=22=20m+2M;全体染色体总长19.16μm,长臂总长10.93μm,核型不对称系数(AS.K%)为57.00%,属于"1A"型,全体染色体总体积为20.30μm3。结论:东方蓼体细胞染色体的数目、核型、体积等清晰准确。 相似文献
69.
Polygonum aviculare (Polygonaceae) is an herb commonly distributed in Mediterranean coastal regions in Egypt and used in folkloric medicine. Organic and aqueous solvent extracts and fractions of P. aviculare were investigated for antimicrobial activities on several microorganisms including bacteria and fungi. Phytochemical constituents of air-dried powered plant parts were extracted using aqueous and organic solvents (acetone, ethanol, chloroform and water). Antimicrobial activity of the concentrated extracts was evaluated by determination of the diameter of inhibition zone against both Gram-negative and Gram-positive bacteria and fungi using paper disc diffusion method.Results of the phytochemical studies revealed the presence of tannins, saponins, flavonoids, alkaloids and sesquiterpenes and the extracts were active against both Gram-negative and Gram-positive bacteria. Chloroform extract gave very good and excellent antimicrobial activity against all tested bacteria and good activity against all tested fungi except Candida albicans. Structural spectroscopic analysis that was carried out on the active substances in the chloroform extract led to the identification of panicudine (6-hydroxy-11-deoxy-13 dehydrohetisane).Evaluation of the antimicrobial activity of panicudine indicated significant activity against all tested Gram-negative and Gram-positive organisms. Panicudine displayed considerable activity against the tested fungi with the exception of C. albicans. Antimicrobial activity of the extracts was unaffected after exposure to different heat treatments, but was reduced at alkaline pH. Studies of the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of panicudine on the tested organisms showed that the lowest MIC and the MBC were demonstrated against Salmonella paratyphi, Bacillus subtilis and Salmonella typhi and the highest MIC and MBC were against Staphylococcus aureus. 相似文献
70.
不同地理来源头花蓼的遗传多样性与没食子酸含量相关性分析 总被引:1,自引:0,他引:1
应用ISSR-PCR和HPLC方法研究了头花蓼的遗传多样性与没食子酸之间的关系。ISSR结果显示居群总的遗传变异较大(Ht=0.2746),居群内的遗传变异较小(Hs=0.0804),居群间的遗传分化大于居群内的遗传分化。没食子酸含量经SPSS17.0分析显示,各居群间和居群内个体的没食子酸含量差异较大,居群间没食子酸含量范围在0.1738%~0.3306%,其中云南腾冲县,贵州台江县、纳雍县、余庆县、晴隆和毕节县居群间没食子酸含量差异均达到显著水平。通过对头花蓼48个地理居群的遗传多样性与没食子酸含量的相关分析,表明云南腾冲,贵州台江、毕节市亮岩镇、晴隆、盘县居群的遗传多样性指数、没食子酸含量较高,不仅可以作为人工育种的选育材料,而且对于头花蓼种植适生地区划研究具有很好的参考价值。 相似文献