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1.
Susceptibility of immature individuals of the spider Theridion impressum to 17 pesticides (6 insecticides, 4 acaricides, 4 fungicides and 3 herbicides) was tested in the laboratory. The pesticides were applied at recommended rates in a Potter tower. Mortality was evaluated for 4 subsequent days. Broad-spectrum insecticides, cypermethrin+chlorpyrofos (Nurelle), α-cypermethrin (Vaztak), and deltamethrin (Decis), were toxic to spiders. Selective insecticides, pirimicarb (Pirimor), Bacillus thuringiensis (Novodor), and triazamate (Aztec), were harmless. All tested acaricides, pirimiphos-methyl (Actellic), flufenoxuron (Cascade), τ-fluvalinate+thiometon (Mavrik), and bifenthrin (Talstar) showed high toxicity. Of the fungicides, dithianon (Delan), benomyl (Fundazol), iprodione (Rovral), and dodine (Syllit), only dithianon was slightly harmful, while the remaining fungicides were harmful. All herbicides, metazachlor (Butisan), clomazone (Command), and clopyralid (Lontrel), were harmless to T. impressum. Three selective insecticides, 3 fungicides and 3 herbicides are recommended for use in plant protection.  相似文献   

2.
三叶草的播种试验   总被引:6,自引:0,他引:6  
对三叶草的2个种的播种、出苗、成坪一系列观察研究结果表明,白三叶海弗(畜)生长较好;白三叶瑞文德(北)、白三叶瑞文德(丹)、红三叶罗亚(兰)和红三叶罗亚(畜)生长适宜;白三叶瑞文德(畜)和白三叶休依(畜)表现欠佳。  相似文献   

3.
黄花补血草组织培养试验   总被引:2,自引:0,他引:2  
黄花补血草既是很好花材又可作药材。通过组织培养试验筛选出了诱导培养基M S BA0.5 NAA0.5,诱导率达92.9%;增殖培养基M S BA0.2 NAA0.2增殖系数为8.7;生根培养基采用1/2M S NAA0.1生根率较高,为65.3%。  相似文献   

4.
将不同地区采集的6种桑树砧木进行盐(NaCl)胁迫处理,根据不同桑种实生苗的相对生长量、盐害指数的统计分析,对桑树砧木耐盐性比较、评价.结果表明,桑树砧木耐盐性由高到低分别是安徽的华桑、新疆的白桑、河北的鲁桑、安徽的鲁桑、江苏的山桑、广东的广东桑.  相似文献   

5.
采用水蒸汽蒸馏法提取分离花梨木叶中的挥发油,通过GC—MS联用仪对花梨木叶挥发油的化学成分进行分析,共鉴定出39个化学成分,主要成分为环己甲酸乙烯酯(5.10%)、三十烷(3.76%)、5,6,7,7a-四氢-4,4,7d-三甲基-2(4H)-苯呋喃酮(3.44%)、二十八烷(3.08%)、十六酸(2.35%)、二十四烷(2.26%)、榄香素(2.25%)、二十烷(2.17%)。  相似文献   

6.
应用水蒸气蒸馏法从多花红千层(Callistemon speciosus)叶提取挥发油,利用气质联用仪(GC-MS)分离鉴定,采用GC峰面积归一法确定其相对含量。挥发油得率为1.34%;分离出29个组分,鉴定了其中的21种化合物,占色谱总馏出峰面积的90.303%,其主要成分是1,8-桉叶素(31.987%)、α-松油醇(14.059%)、3-硝基乙醇(13.264%)、瓜菊醇酮(9.246%)、松油醇-4(6.038%)等。  相似文献   

7.
Chen HY  Ye XL  Cui XL  He K  Jin YN  Chen Z  Li XG 《Fitoterapia》2012,83(1):67-73
Generally, berberine, coptisine, palmatine, and jatrorrhizine were considered as the main bio-active compounds in Rhizoma Coptis (RC). Little attention was paid to investigate the pharmacological activity of minor constituents in RC. The present study was designed to separate the minor compounds, and the cytotoxicity and antihyperglycemic effect of these compounds in HepG2 cells were also studied. Palmatine (1), berberine (2), coptisine (3), epiberberine (4), columbamine (5), and jatrorrhizine (6) from RC ethanol extract were isolated by high speed counter current chromatography (HSCCC) in one run. The remaining fraction (about 50% of extract in HSCCC) was further isolated by traditional column chromatography methods to yield magnoflorine (7), ferulic acid (8), and choline (9). Another four alkaloids, namely groenlandicine (10), berberrubine (11), oxyberberine (12), 8-oxo-coptisine (13), also were obtained from CHCl3 extracts. Especially, choline was first isolated from RC. Cell assay indicated that the minor fractions excluding compounds 1-6 showed obvious glucose lowering activity. In addition, the minor monomers also exhibited moderate glucose lowering activity. The combination of berberine and ferulic acid showed synergistic effect on antihyperglycemic. The combination of alkaloids 1-6 was same so. All compounds had different cytotoxicity in HepG2 cells within the test concentration. Of them, berberrubine showed the strongest cytotoxicity. The results suggested that combined action of variety constituents contributed to the antihyperglycemic effets and low cytotoxicity of RC extract in HepG2 cells.  相似文献   

8.
This study describes the dispersal phenology and syndromes in Gutianshan 24 ha plot in a subtropical broad-leaved forest of China. The 130 0.5 m2 seed traps collected 69,115 mature seeds, representing 27 species (belonging to 24 genera, and 15 families) in 12 months. One marked peak in the number of seeds and species during the year was found in dry season (November). Zoochory was the most common dispersal syndrome (70.4%), followed by anemochory (18.5%), ballistic dispersal (11.1%). Among fruit types, berry (33%), capsule (22%), nut (18%), and drupe (11%) were common in the subtropical evergreen forest. In fruit color, brown was the commonest (40%), followed by dark brown (30%), black (15%), red (11%), and yellow (4%). Overall, the community level seed rain study revealed that one marked peak in seed number occurred in the middle of dry season; zoochory was the principal dispersal mode of woody plants in subtropical forest, and dry seasons favor seed dispersal by animal and wind.  相似文献   

9.
A HPLC-UV method for the quantification of six major isoflavonoids, calycosin 7-O-beta-D-glucoside (1), formononetin 7-O-beta-D-glucoside (2), (6alphaR, 11alphaR) 3-hydroxy-9,10-dimethoxypterocarpan-3-O-beta-D-glucoside (3), 7,2'-dihydroxy-3',4'-dimethoxyisoflavan-7-O-beta-D-glucoside (4), calycosin (5) and formononetin (6), in Radix Astragali (Huangqi) was developed and validated. The method was proven to be sensitive, specific, accurate and precise, as well as effective and easy.  相似文献   

10.
Forty-two genotypes were evaluated for juvenile wood yield and its components at three locations in Bihar, India. A significant difference was observed among the genotypes for all the characters under study. The highest value of genotypic and phenotypic coefficients of variation was observed in juvenile wood volume followed by diameter at breast height (DBH). Characters like plant height, clear bole height, crown diameter number of branches, angle of branch, diameter of branch, and length of branch showed moderate values for genotypic and phenotypic coefficients of variation. Very high heritability was estimated for clear bole height, crown diameter, angle of branch, and length of branch. Diameter and plant height showed moderate to high heritability. Relatively genetic advance expressed in percentage of mean or genetic gain was observed the highest in volume (30.86%), DBH (18.96), clear bole height (17.19%), angle of branch (17.39), length of branch (19.53), and in plant height (11.87%). Juvenile wood volume per plant showed significant and positive correlation with height (0.619), diameter (DBH, 0.770), clear hole height (0.305), number of branch (0.372); and positive association with crown diameter (0.145), angle of branch (0.055), diameter of branch (0.251), length of branch (0.200), and survival (0.166); and significant negative correlation with taper (?0.499) at the phenotypic level. In phenotypic path analysis diameter (DBH, 0.702), plant height (0.169), crown diameter (0.121), taper (0.027), and survival (0.050) showed positive direct effect on juvenile wood volume. The direct impact of the same through clear bole height (?0.366), number of branch (?0.130), angle of branch (?0.228), and length of branch (?1.567) was negative. Hence it is suggested that due importance should be given to diameter (DBH), plant height, crown diameter, diameter of branch, taper, and survival for selection of superior plant with high juvenile wood yield potential in poplar.  相似文献   

11.
巯基纤维素处理重金属废水研究   总被引:10,自引:0,他引:10  
纤维素与硫代乙醇酸在乙酸酐和乙酸介质中发生酯化反应,合成巯基纤维素(SC)。含重金属的废水中加入碱调节废水pH值至9~10,静置、过滤。滤液用酸调pH值至5~7后流经SC管,去除废水中镉、铅、铜、汞等重金属。SC用稀盐酸淋洗再生。对使用和再生条件及吸附机理进行了研究。实验结果:SC中巯基含量大于2%时,每公斤SC对金属离子的吸附容量大于0.2mol;处理水中镉、铅、铜、汞浓度低于0.05mg/L;SC再生后可循环使用。  相似文献   

12.
This tropical ant was found 1982 in Halle-Neustadt (kindergarden), 1985 in Rostock (bakery), 1994 in Hamburg (dwelling-house), 1996 in Salzgitter-Lichtenberg (dwelling-house) and since 1994 also observed and controlled in Berlin (dwelling-houses). Important exterior characteristics are: size 1.3–1.5 mm (worker), 2.3–2.5 mm (female and male), petiolus its not scale-like, gaster with 4 from dorsal visible segments. Colour: caput blackbrown to black; gaster is cream to brownyellow (worker), brownish (female), blackbrown to black (male), coloured. Their behaviour distinguished them fromMonomorium pharaonis: they run very quickly and restlessly, “ant roads” are not longer than 6–8 hours existent. Preferred food: lying about food, dead flies and cockroaches, cake, milk, sweets. This species was fed in laboratory with mixture from yolkpowder, biskuitmeal and honey, dead insects. The inquiry of attack-locality results with pig-lever or saturated sugar-solution. Baits-boxes were placed on the attack-locality directly. It was distinctly, that Maxforce-Bait (Hydramethylnon) was visited middling. Baits with a mixture of peanut-fat and boric or of yolkpowder, honey and boric were attractive about a longer time and effective in the control. T. melanocephalum was introduced likely with tropical flowers and fruits, sweets or baking from subtropical-tropical region in dwelling houses.  相似文献   

13.
Increasing demand for renewable energy and limiting CO2 emissions have stimulated much interest in wood-based biofuels. Unfortunately, expanding the utilization of forest biomass may cause nutrient depletion in forested environments. This study investigates the element content from various parts of the tree. Comparisons were made between different harvesting scenarios and their impact on the amount of nutrients removed from the forest environment. The harvesting scenarios were: stem-only harvesting (SOH), branch and stem harvesting (BSH), and two variants of whole-tree harvesting (WTH). The elements taken into account were: carbon (C), nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), sodium (Na), sulphur (S), copper (Cu), iron (Fe), nickel (Ni), manganese (Mn), zinc (Zn), cadmium (Cd), chromium (Cr) and lead (Pb). To make the results comparable, the same amount of removed biomass was taken into calculation. The differences between harvesting scenarios were significant. The amounts of removed elements formed similar pattern: the lowest level was found in SOH, average in BSH, and highest in both variants of WTH. This confirms that the application of WTH is connected with increased risk of nutrient depletion, even when the volume of harvest would be equal to other variants.  相似文献   

14.
米老排人工林生物量研究   总被引:7,自引:2,他引:7  
采用相对生长方程模拟从南亚热带引种的米老排林分生物量。结果表明:15年生米老排人工林分的生物量为195.972 t.hm-2,其中乔木层为194.772 t.hm-2,林分平均净生产量为15.610 t.hm-2a-1,其中乔木层为15.185t.hm-2a-1。乔木层中树干(包括树皮)、枝、叶和根系的生物量分别为99.664 t.hm-2、24.829 t.hm-2、5.074 t.hm-2和65.165 t.hm-2。乔木层叶面积指数5.274,叶的净同化率为329.2 g.m-2a-1。极端最低气温-8℃左右对生物量的增长产生负面影响。  相似文献   

15.
Trace metal accumulation in tree rings of Jeffrey pines (Pinus jeffreyi) from the Lake Tahoe basin (Sierra Nevada, CA, USA) was determined using high resolution inductively coupled plasma mass spectrometry (HR-ICP–MS). The objectives of this study were (1) to establish baseline values for aluminium (Al), chromium (Cr), manganese (Mn), iron (Fe), cobalt (Co), nickel (Ni), copper (Cu), zinc (Zn), strontium (Sr), cadmium (Cd), barium (Ba), and lead (Pb); (2) to investigate the intra-tree and inter-tree variability of these trace metals, and (3) to assess differences in metal concentrations related to automobile traffic. Two field collection sites were selected with similar ecologic attributes, one proximal to a heavily traveled highway, and the other isolated from any local source of auto emissions. At each site two trees with similar features were selected, and two increment cores collected from each tree. Cores were cross-dated, cleaned of contamination, dissected into 5-year increments, ashed, and acid digested, before analysis by HR-ICP–MS. Time series spanning 191–326 years were developed for the 12 trace metals. Variability was high within and between trees, most likely because of physiologic mechanisms for element sequestration and allocation. The best intra-tree correlation was found for Ba, Sr, Mn, and Co; of these elements, Co showed an overall increase over time, whereas Sr and Ba displayed an opposite trend, and Mn fluctuated over time. Mean Co concentration at the near-highway site was higher, whereas mean Sr, Ba, and Mn concentrations were lower, than at the control site.  相似文献   

16.
利用正交试验进行了丁香的幼胚离体培养和增殖培养两方面的研究,对基本培养基、糖浓度、谷氨酰胺浓度、BA浓度、NAA浓度都进行了仔细的筛选。结果表明:幼胚培养的最适胚龄为50天;幼胚培养所需要的最适培养基为附加BA(0.1mg稬-1)、NAA(0.001mg稬-1),糖50(g稬-1),Gln(400mg稬-1)的Monnier培养基,幼胚萌发率可达91.7%;Gln的加入对幼胚培养有显著影响。此外,丁香实生苗最适的增值培养基为MS+BA(2mg稬-1)、NAA(0.01mg稬-1)、IBA(0.5mg稬-1)、Gln(100mg稬-1),此时繁殖系数大于3.6,可以满足生产需要。图1表7参8。  相似文献   

17.
采用超临界CO2流体萃取法(SFE-CO2)和水蒸气蒸馏法(SD)从川桂叶中提取挥发油,利用气相色谱-质谱联用技术,分析了挥发油的化学组成,并进行了比较.结果表明:两种方法所得挥发油存在较大差别,超临界CO2流体萃取得到挥发油的产率为1.6%,主要成分是香豆素(32.5%),芳樟醇(19.9%),棕榈酸(10.4%),而水蒸气蒸馏法得到挥发油的产率为0.9%,主要成分是芳樟醇(69.0%)、丁香烯(4.6%)、氧化丁香烯(2.7%).  相似文献   

18.
ABSTRACT

An individual-tree basal area increment model was developed for masson pine based on 26276 observations of 13,138 trees in 987 sample plots from the 7th (2004), 8th (2009), and 9th (2014) Chinese National Forest Inventory in Hunan Province, South-central China. The model was built using a linear mixed-effects approach with sample plots included as random effects since the data have a hierarchical stochastic structure and biased estimates of the standard error of parameter estimates could be a consequence of applying ordinary least square (OLS) for regression. In addition, within-plot heteroscedasticity and autocorrelation were also considered. The final mixed-effects model was determined according to the Akaike information criterion (AIC), Bayesian information criterion (BIC), log-likelihood (Loglik), and the likelihoodratio test (LRT). The results revealed that initial diameter (DBH), the sum of the basal area (m2/ha) in trees with DBHs larger than the DBH of the subject tree (BAL), number of trees per hectare (NT), and elevation (EL) had a significant impact on individual-tree basal area increment. The mixed-effects model performed much better than the basic model produced using OLS. Additionally, the variance structure of the model errors was successfully modeled using the power function. However, the autocorrelation structures were not defined because there was no autocorrelation amongst the data. It is believed that the final model will contribute to the scientific management of the masson pine.  相似文献   

19.
The chemical composition of the essential oil obtained from Grindelia robusta aerial parts from central Italy was analyzed by GC and GC/MS and 45 components were identified. Borneol (15.2%), alpha pinene (10.3%), trans-pinocarveol (7.0%), bornyl acetate (4.5%), limonene (4.3%) were the main components. The antioxidant activity of the essential oil was evaluated using the DPPH and 5-lipoxygenase tests.  相似文献   

20.
以云南引种的46株元宝枫的果实为研究材料,对其果实的9个性状变异和各性状间的相关性进行了分析研究。结果表明,(1)果实性状的株间变异较株内变异显著;(2)果实各性状变异系数由大到小依次为空壳比率、果实厚度、种子千粒重、果实千粒重、着生痕长度、种子厚度、果实宽度、带翅果实长度、果实长度;(3)果实千粒重与种子千粒重呈高度正相关,与果实宽度、种子厚度、果实厚度呈显著正相关,与带翅果实长度、着生痕长度及果实长度呈低度正相关。种子千粒重除了与果实千粒重呈高度正相关外,还和带翅果实长度、种子厚度、果实厚度呈显著正相关,而且和果实宽度呈低度正相关。以此评选出引种地果实性状优良、产量高的元宝枫单株。  相似文献   

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