牛心朴子提取物抑菌效果研究

采用菌丝生长速率法测定了3种牛心朴子提取物对番茄早疫病菌和番茄灰霉病菌的抑制作用。结果表明,当供试浓度为500mg/L时,牛心朴子总生物碱、牛心朴子甾体皂苷和牛心朴子总黄酮对番茄病原菌菌丝生长均有一定的抑制作用,其中牛心朴子总生物碱的抑菌活性最高,抑制率可达85%以上。牛心朴子总生物碱对番茄早疫病菌和番茄灰霉病菌的EC50分别为84.3471mg/L和135.8679mg/L。牛心朴子总生物碱可作为植物源杀菌剂进一步研究开发。     

阿维菌素和天敌瓢虫对枸杞蚜虫的控制效果评价

以常规防治农药吡虫啉做对照,比较高效广谱抗生素农药阿维菌素和天敌昆虫瓢虫对枸杞田枸杞蚜虫的防治效果.结果表明:施用1.8%阿维菌素EC 2.5 mg/kg药后5 d和10 d的防效分别为54.0%和23.0%;2.5%吡虫啉WP 25 mg/kg 5 d和10 d的防效分别为71%和35%,对枸杞蚜虫防效理想.释放天敌昆虫瓢虫后5 d和10 d防效分别为-321.0%和-422.0%,防效差,单纯释放天敌瓢虫不能有效控制枸杞蚜虫的危害.     

不同方法提取牛心朴子基因组DNA效果的比较研究

以牛心朴子的叶片、茎段、根为试材,采用改良的CTAB法Ⅰ、CTAB法Ⅱ和SDS法对其进行了基因组DNA提取效果的比较分析.结果表明.CTAB法Ⅰ从3个部位都能提出较高浓度的DNA,电泳条带完整清晰;CTAB法Ⅱ从3个部位都能提出DNA,条带明亮,但有明显拖尾现象;SDS法从叶片中能提出较高的DNA,但从茎和根中所提的DNA含量较小,电泳条带暗;3种方法所提的DNA其RAPD扩增效果以CTAB法Ⅰ最好,CTAB法Ⅱ次之,SDS法最差.叶片提取的DNA平均纯度、浓度和得率为最高,RAPD扩增效果最好,茎次之,根最低.说明CTAB法工是牛心朴子DNA的高效提取方法,不同部位以牛心朴子叶子提取的DNA得率高,扩增效果最好.     

宁夏枸杞白粉病有机防治初探

以"黄果"枸杞为试材,清水、25%三唑酮药剂为对照处理,研究了不同浓度解淀粉芽孢杆菌和橘皮精油+3%苦参碱对枸杞白粉病的有机防治效果。结果表明:施药7d后,解淀粉芽孢杆菌250倍液对枸杞白粉病的防治效果为22.86%,橘皮精油650倍液+3%苦参碱防治效果为50.41%,25%三唑酮药液的防治效果为75.61%。橘皮精油+3%苦参碱对宁夏枸杞白粉病有机防治效果更为理想。     

山豆根组培苗的质量分析

以山豆根组培生根苗为试材,采用TLC法鉴别其是否存在苦参碱和氧化苦参碱,并使用HPLC法测定其组培苗移栽前后苦参碱和氧化苦参碱的含量。结果表明:山豆根组培生根苗含有苦参碱和氧化苦参碱,且与氧化苦参碱和苦参碱对照品色谱相同的位置上,显示相同的橙红色斑点;HPLC定量分析结果表明,山豆根组培苗移栽田间4个月含有的苦参碱和氧化苦参碱均低于田间生长6个月的山豆根实生苗。     

德令哈枸杞蚜虫毒力测定及田间药效试验

用13种杀虫剂对枸杞蚜虫进行室内毒力测定,5种杀虫剂进行田间药效研究。结果表明:13种杀虫剂中对枸杞蚜虫的LD50的敏感性较小的为16%四螨.哒螨灵WP、48%毒死蜱EC、3%三氟氯氰菊酯EC,敏感性较大的为1.8%阿维.吡虫啉WG、4.2%高氯.甲维盐EC、20%瀚生尖峰WP。在田间防治枸杞蚜虫时,70%噻虫嗪ZC、3%啶虫脒EC及25%阿克泰WG防治蚜虫效果好,但3%啶虫脒EC及25%阿克泰WG的持效期长,在药后第15天防效仍可达80%以上。     

瓜类病虫害防治用药选择与复配的大数据挖掘

综合分析2010年1月1日后登记的瓜类上农药单剂和病虫害的对应关系,构建了"瓜类病虫害防治用药一张图";并用多维尺度图展示了瓜类复配药剂中不同单体的组合频次.推荐如下用药种类:(1)蓟马:吡虫啉>多杀霉素≈乙基多杀菌素;(2)潜叶蝇:噻虫嗪;(3)蚜虫:苦参碱;(4)鳞翅目幼虫:溴氰虫酰胺≈氯虫苯甲酰胺;(5)粉虱:溴...     

仿生胶对枸杞害虫的防控技术研究

研究了仿生胶封园对枸杞害虫种群动态的影响,结果表明,初春和秋季采用仿生胶封园,明显推迟了枸杞蚜虫、木虱和瘿螨的发生期,可有效压低枸杞蚜虫、枸杞木虱、枸杞瘿螨等害虫的虫口数,明显降低害虫对枸杞的为害水平,且仿生胶的使用不影响枸杞树萌芽、展叶和果实品质。     

藜芦碱对枸杞蚜虫室内活性测定及安全性评价

以枸杞蚜虫为研究对象,采用浸虫法测定藜芦碱对枸杞蚜虫(成虫、若虫)的室内毒力,采用药害评价法测定藜芦碱对枸杞树生长发育的使用安全性。结果表明:供试药剂0.5%黎芦碱SLX与1%黎芦碱TKL对枸杞成蚜的毒力相当,0.5%黎芦碱SLX对枸杞若蚜的毒力略高于1%黎芦碱TKL,枸杞若蚜对藜芦碱的敏感性高于枸杞成蚜。黎芦碱制剂对枸杞树的叶片、花、果实均无药害产生,田间使用安全。     

苦参碱在果树上的应用

<正>苦参是我国常见的一种有传统医药价值的豆科落叶灌木。从苦参中提取的苦参碱物质具有杀虫抑菌和刺激植物生长的综合功效。研究表明,从苦参植物中分离出的27种生物碱中,除极少数为双哌啶类生物碱外,主要为喹嗪啶类生物碱。苦参碱(化学分子式:C15H21N20)农药产品是指从苦参中提取的全部活性物质。苦参碱对害虫具有触杀、胃毒、内吸、忌避、拒长、绝育、干扰、脱皮、麻痹神经中枢系统及致虫体蛋白凝固、     

Relationship between renal hypertension and cardiac α1-adrenoceptor autoantibodies in rats

AIM: To examine the autoantibody against α₁-adrenoceptor and its biologic activities during the development of renal hypertension. METHODS: Renal hypertension of rat was achieved by clipped renal artery, the titre of autoantibody to α₁-adrenoceptor was detected using ELISA immunoassay. Furthermore, the biological offects of these autoantibodies on cultured cardiomyocytes were also examined. RESULTS: After two weeks of clipping renal arteries, both the frequency of occurrence and the titre of autoantibodies to cardiac α₁-adrenergic receptor were significantly increased as compared with the control of pre-treatment. The increased autoantibodies lasted for several weeks and then automatically decreased gradually to the pre-clipping level at 12 weeks. The biological effects of these autoantibodies displayed an "agonistic-like" activities on the beating frequency of cultured neonatal cardiomyocytes. CONCLUSION: Autoantibodies against α₁-adrenoceptor may play a role in the elevation of peripheral vascular resistance and in the development of cardiac hypertrophy in rats with renal hypertension.     

Influence of Mineral Nutrients on Strawberry Fruit Quality and Their Accumulation in Plant Organs

Abstract

This review is based partly on complete articles and partly on abstracts. Three of the 60 articles deal with the total uptake of elements in strawberry plant organs in two different strawberry production systems, both considered as optimal concerning amount and balance of elements. The effect on fruit quality may be dramatic if the level of a particular element is outside this range, but there may also be effects initiated by differences within the optimal range of elements. Most articles refer to product oriented quality, but some focus on consumer oriented quality, as discussed by Shewfelt (1999). The discussion here is on a general basis, so one should keep in mind that there are cultivar differences and that specification of nutrition ideally should mirror the needs of a single cultivar, or a group of cultivars with similar requirements. Also, to get a complete understanding of the subject future reviews should embrace a broader access of information including the effect on plant development of individual elements, such as the role of calcium in fruit firmness and its importance in cell wall structure. However, the intention here is to narrow the information to results that suggest a direct connection between nutrient uptake and fruit quality.     

Mixed-severity fire regime in a high-elevation forest of Grand Canyon,Arizona, USA

Fire regime characteristics of high-elevation forests on the North Rim of the Grand Canyon, Arizona, were reconstructed from fire scar analysis, remote sensing, tree age, and forest structure measurements, a first attempt at detailed reconstruction of the transition from surface to stand-replacing fire patterns in the Southwest. Tree densities and fire-/non-fire-initiated groups were highly mixed over the landscape, so distinct fire-created stands could not be delineated from satellite imagery or the oldest available aerial photos. Surface fires were common from 1700 to 1879 in the 4,400 ha site, especially on S and W aspects. Fire dates frequently coincided with fire dates measured at study sites at lower elevation, suggesting that pre-1880 fire sizes may have been very large. Large fires, those scarring 25% or more of the sample trees, were relatively infrequent, averaging 31 years between burns. Four of the five major regional fire years occurred in the 1700s, followed by a 94-year gap until 1879. Fires typically occurred in significantly dry years (Palmer Drought Stress Index), with severe drought in major regional fire years. Currently the forest is predominantly spruce-fir, mixed conifer, and aspen. In contrast, dendroecological reconstruction of past forest structure showed that the forest in 1880 was very open, corresponding closely with historical (1910) accounts of severe fires leaving partially denuded landscapes. Age structure and species composition were used to classify sampling points into fire-initiated and non-fire-initiated groups. Tree groups on nearly 60% of the plots were fire-initiated; the oldest such groups appeared to have originated after severe fires in 1782 or 1785. In 1880, all fire-initiated groups were less than 100 years old and nearly 25% of the groups were less than 20 years old. Non-fire-initiated groups were significantly older (oldest 262 years in 1880), dominated by ponderosa pine, Douglas-fir, or white fir, and occurred preferentially on S and W slopes. The mixed-severity fire regime, transitioning from lower-elevation surface fires to mixed surface and stand-replacing fire at higher elevations, appeared not to have been stable over the temporal and spatial scales of this study. Information about historical fire regime and forest structure is valuable for managers but the information is probably less specific and stable for high-elevation forests than for low-elevation ponderosa pine forests.This revised version was published online in May 2005 with corrections to the Cover Date.     

瓜叶绿素降解关键酶基因PPH和PAO cDNA片段的克隆与表达初步分析

 以西双版纳黄瓜和‘华黄5号’黄瓜叶片为试验材料,研究了衰老过程中两种黄瓜叶片叶绿素含量变化及脱镁叶绿素脱镁叶绿酸水解酶基因PPH和脱镁叶绿酸a加氧酶基因PAO的表达。结果表明：随着叶片衰老,叶绿素a和叶绿素b含量显著降低,叶绿素a与叶绿素b的比值在0.5左右,推测叶绿素b的含量可能对黄瓜叶片保绿起到重要作用。荧光定量RT-PCR分析结果显示：PPH和PAO在西双版纳黄瓜叶片生长35 d时表达量最高,分别为5.50和1.86;PPH在‘华黄5号’叶片35 d时表达量最高,为7.14,而PAO在35和45 d表达量都很高,分别为3.90和3.91;PPH和PAO在西双版纳黄瓜叶片中的表达量低于在‘华黄5号’中。     

Effects of simvastatin on PDGF-BB and serum-induced proliferation of vascular smooth muscle cells and on the expression of tumor suppressor gene PTEN

AIM:To observe the effect of simvastatin on the proliferation of vascular smooth muscle cells(VSMCs) induced by serum and growth factor PDGF-BB and the effect of simvastatin on the expression of PTEN,a important regulator of G₁/S cell cycle transition. METHODS:The DNA synthesis was determined by [³H]-TdR incorporation, cell cycle was examined with flow cytometry, the protein level of PTEN was measured by Western blot method. RESULTS: (1)Simvastatin inhibited [³H]-TdR incorporation in a dose dependent manner. (2) Flow cytometric DNA analysis revealed that simvastatin induced significantly enhancement of G₀/G₁ phase and decrease in S phase VSMCs.(3)Simvastatin increased protein level of PTEN and mevalonate, a metabolite of HMG-COA, reversed the effect of simvastatin on PTEN protein expression. CONCLUSION:Simvastatin may inhibit proliferation of VSMCs and retarded cell cycle in G₀/G₁ phase by increasing PTEN expression through inhibiting synthesis of mevalonate.     

Relationships of landscape,prey and agronomic variables to the abundance of generalist predators in cotton (<Emphasis Type="Italic">Gossypium hirsutum</Emphasis>) fields

A two-year field study investigated the possible effects of grain sorghum (Sorghum bicolor [L.] Moench) and uncultivated areas on the abundance of generalist predators in commercially-managed cotton (Gossypium hirsutum L.) fields in Texas, USA. From 63 to 70 fields were sampled for pests and predators over nine consecutive weeks during early stages of cotton development. Additional data on agronomic practices and landscape composition at three spatial scales were also collected for each field. Stepwise regression analyses were used to determine the relationships of landscape, agronomic and prey variables to the abundance of generalist predators. Because the variables most closely linked to predator levels could vary over time, separate regressions were conducted for three time periods corresponding to stages of grain sorghum growth (half-bloom, hard-dough, maturity) in each year. Significant relationships between predator abundance and agricultural landscape composition appear in both years and in all three time periods, but the specific relationships of landscape variables to cotton predator levels differed between and within years. At maturity in 2001, predator levels rose as the amount of uncultivated land from 1.6 to 3.2 km distant and the perimeter shared with grain sorghum increased. During 2002, the area of grain sorghum (half-bloom) and uncultivated land (hard-dough) within 1.6 km of cotton fields were both positively related to predator numbers. Cotton planting dates and the abundance of cotton fleahoppers (Pseudatomoscelis seriatus [Reuter]) were also strongly linked to predator numbers during both years. Results suggest that the total amount of grain sorghum or uncultivated land in an area is more important than the presence of these habitats adjacent to cotton fields, and that landscape composition may sometimes be the most important factor in determining predator abundance.     

Influence of lanthanum nitrate on the expression of aquaporin 7 in the testis of rats

AIM: To find out whether different dosage of rare earth element-lanthanum can influence the expression of aquaporin 7(AQP 7) in the testis of rats. METHODS:Rats were fed with lanthanum nitrate[La(NO₃)₃]and killed 6 months later.Testes were then removed immediately to extract total RNA.Northern blot analysis is performed finally. RESULTS:0.1 mg/kg La(NO₃)₃ depressed the expression of AQP 7 in rat testis, while 20 mg/kg La(NO₃)₃ had no significant effect on it. CONCLUSION: AQP 7 expession is found in the rat testis; La(NO₃)₃ can depress the expression of AQP 7 in the rat testis.     

Ergebnisse der Leistungsprüfung von Kirschensorten auf wuchsreduzierenden Unterlagen in Ungarn

Zusammenfassung In Ungarn gibt es ein reges Interesse an intensivem Obstanbau. Der Erfolg dieses Anbaus hängt in sehr großem Maße von den Wechselwirkungen zwischen dem Standort, den Sorten-Unterlagen-Kombinationen und dem Anbauverfahren ab.Um die Wirkung wuchsreduzierender Kirschenunterlagen aus ausländischen Züchtungsinstituten unter ungarischen Klimaverhältnissen untersuchen zu können, wurde im Forschungsinstitut für Obst- und Zierpflanzenbau Budapest-Érd ein Vergleichsversuch durchgeführt. Der Versuch wurde mit Cerasus avium C. 2493, Weiroot 13, Weiroot 53, Weiroot 72, Weiroot 154, Weiroot 158, GiSelA 5 und P-HL-A-Unterlagen 1997 in der Versuchsanstalt des Forschungsinstituts für Obst- und Zierpflanzenbau Budapest-Érd aufgepflanzt. Als Kontrolle diente die Sämlingsunterlage Cerasus mahaleb Cema, deren Anteil im ungarischen Süßkirschenanbau bei 70–80% liegt. Die Unterlagen wurden mit drei Süßkirschensorten (Germersdorfi , Linda, Katalin) und mit einer Sauerkirschensorte (Piramis) veredelt.Nach der Wüchsigkeit bis zum Ende des 8. Standjahres konnten die Unterlagen in drei Gruppen eingeteilt werden: starkwüchsige (Cerasus mahaleb Cema, Cerasus avium C. 2493, Weiroot 13), mittelstarkwüchsige (Weiroot 158, Weiroot 154, P-HL-A) und schwachwüchsige Unterlagen (Weiroot 72, Weiroot 53, GiSelA 5). Die stärkste Neigung, Wurzelschosse zu treiben, zeigten Weiroot 13 und Weiroot 154.Während der Untersuchung der generativen Eigenschaften wurde beobachtet, dass es Unterschiede in der Blütezeit der Sorten-Unterlagen-Kombinationen gibt. Auf GiSelA 5 veredelte Sorten blühten 1 oder 2 Tage früher als die Kontrolle. Es gab nur geringe Unterschiede in der Reifezeit der Kombinationen. Den größten Ertrag hatte die Sorte Linda, gefolgt von Katalin, Germersdorfi 3 und Piramis. Der größte Fruchtdurchmesser wurde bei der Süßkirschensorte Germersdorfi 3 gefunden, der größte Anteil an Früchten größer als 26 mm bei den Bäumen auf Weiroot 72 (23%), der geringste Anteil großer Früchte bei den Bäumen auf GiSelA 5. Bei Piramis wurde der größte Fruchtdurchmesser auf Cerasus avium C. 2493 gemessen.     

Effects of corridors on home range sizes and interpatch movements of three small mammal species

Corridors are predicted to benefit populations in patchy habitats bypromoting movement, which should increase population densities, gene flow, andrecolonization of extinct patch populations. However, few investigators haveconsidered use of the total landscape, particularly the possibility ofinterpatch movement through matrix habitat, by small mammals. This studycompares home range sizes of 3 species of small mammals, the cotton mouse(Peromyscus gossypinus), old-field mouse (P.polionotus) and cotton rat (Sigmodon hispidus)between patches with and without corridors. The study site was in S. Carolina,USA. Corridor presence did not have astatistically significant influence on average home range size. Habitatspecialization and sex influenced the probability of an individual movingbetween 2 patches without corridors. The results of this study suggest thatsmall mammals may be more capable of interpatch movement without corridors thanis frequently assumed.This revised version was published online in May 2005 with corrections to the Cover Date.     

Quercetin regulates Fas expression and induces apoptosis in hepatocellular carcinoma HepG2 cells

AIM: To investigate the role of 1, 4, 5- trisphosphate inositol (IP3) and Fas gene expression in apoptosis of HepG2 cells induced by quercetin. METHODS: HepG2 cells were treated with quercetin at different concentrations (including 20, 40, 60, 80 μmol/ L) for 72 h and treated with 60 μmol/ L quercetin for 6 h, 12 h, 24 h, 48 h and 72 h. IP3, Fas mRNA, Fas protein and apoptosis rate were assayed by IP3 - ［3H］ Birtrak assay, RT-PCR, Western blotting and flow cytometry, respectively. RESULTS: When HepG2 cells were incubated with different concentrations of quercetin for 72 h, the IP3 content was lower than those in control. Fas mRNA expression, Fas protein expression and the apoptosis rate were higher than those in control. When HepG2 cells were incubated with quercetin for 6 h, 12 h, 24 h, 48 h, 72 h, the IP3 contents were lower than those in control incubated with 60 μmol/L quercetin for 12 h. Fas mRNA expression was higher than that in control incubated with 60 μmol/L quercetin for 12 h . Fas protein expression was higher than that in control. The apoptosis rate was significantly higher than that in control incubated with 60 μmol/L quercetin for 24 h (P<0.01). CONCLUSION: Quercetin induces apoptosis of HepG2 cells by reducing IP3 production and upregulating Fas gene expression.