不同保存方式对扁桃花粉保存效果的影响

采用干燥法和玻璃化法2种方法,对新疆莎车县扁桃品种晚丰18号花粉进行了超低温保存研究。结果表明:晚丰18号花粉最佳干燥方式为4℃硅胶干燥,适宜干燥时间为6⁸ h,干燥6h和8 h的花粉含水量分别为53.74%、52.74%,超低温保存后花粉萌发率为61.22%、63.77%,相对保存率为91.68%、97.13%;在室温(20±1)℃下以玻璃化液PVS2(30%甘油+15%乙二醇+15%二甲基亚砜+0.4 mol/L蔗糖)处理208 h,干燥6h和8 h的花粉含水量分别为53.74%、52.74%,超低温保存后花粉萌发率为61.22%、63.77%,相对保存率为91.68%、97.13%;在室温(20±1)℃下以玻璃化液PVS2(30%甘油+15%乙二醇+15%二甲基亚砜+0.4 mol/L蔗糖)处理20³0 min后,超低温保存的花粉萌发率最高,为40.88%30 min后,超低温保存的花粉萌发率最高,为40.88%⁴1.53%;不同解冻方式间花粉萌发率差异极显著,以35℃解冻70 s的萌发效果最好;干燥法保存效果较玻璃化法保存好,超低温保存时间对花粉萌发率无显著影响。     

地被菊花粉活力和储藏性研究

 以地被菊（groundcover chrysanthemum）品种‘毛白玉’、‘粉芙蓉’的新鲜花粉为材料,采用离体萌发法对花粉活力进行测定,并观察花粉萌发及花粉管生长情况。试验结果表明：外源Ca²⁺显著促进了花粉萌发和花粉管生长,硼酸对花粉萌发没有显著影响;花序中部筒状花的花粉活力显著高于花序外部和内部筒状花的花粉;遮荫降低了花粉活力;‘毛白玉’和‘粉芙蓉’花粉在室温下可分别储藏8和6 d,4 ℃下可分别储藏25 d和20 d,–20 ℃下可储藏25 d,–80 ℃下可分别储藏21和18 d。–80 ℃储藏前干燥处理2 h的花粉,储藏后花粉活力显著高于干燥处理4 h和6 h的花粉。预冻处理显著降低了花粉活力。–80 ℃储藏的花粉采用35 ℃解冻2 min或冰上解冻效果较好。     

金太阳杏花粉超低温保存方法研究

为探讨杏花粉种质保存的方法,进而为花粉培养、遗传转化和杂交育种提供材料,以杏品种金太阳的新鲜成熟花粉为试材,采用干燥法和玻璃化法2种超低温保存技术,对花粉干燥时间、解冻方式和贮藏时间等影响保存后花粉萌发率的有关因素进行研究。结果表明,干燥时间对金太阳杏花粉超低温保存后的萌发率有显著影响,其中干燥法宜在4℃下硅胶干燥8h、玻璃化法宜在(20±1)℃下以玻璃化液PVS2(体积分数15%二甲基亚枫+15%乙二醇+30%甘油+0.4mol/L蔗糖)处理60min;干燥法保存后分别以4℃2h、20℃30min和40℃70s等3种方式化冻,花粉萌发率无明显差别,而对玻璃化法则以40℃70s化冻后的花粉萌发率最高;以2种方法分别保存1、10、30、60d后花粉萌发率无显著变化。     

不同条件下牡丹花粉的贮藏寿命

以2个牡丹品种“凤丹白”和“鲁荷红”为试材,以花粉萌发率和授粉结实率为依据,研究了室温(25℃)、4、-20、-86℃条件下的牡丹花粉贮藏寿命,以建立花粉贮藏技术.结果表明:牡丹花粉室温下保存7d、4℃下保存90 d、-20℃下保存180 d仍有很高的萌发率,-86℃下贮藏la,花粉萌发率没有明显下降、授粉结实率高.室温干燥24 h花粉贮藏后萌发率显著高于未干燥花粉.温度和含水量是影响牡丹花粉贮藏寿命的重要因素.自来水冲洗解冻效果最好.4℃和-86℃贮藏是解决牡丹育种花期不遏的有效措施.     

桔梗花粉贮藏研究

通过研究不同干燥处理、不同贮藏温度对桔梗花粉生活力的影响,阐明贮藏过程中桔梗花粉生活力的变化规律.结果表明:桔梗花粉45℃脱水干燥4h,花粉生活力明显下降,但干燥处理后的脱水花粉其耐贮藏性明显高于正常花粉;随着贮藏天数的增加桔梗花粉生活力逐渐下降,但10℃、4℃、-20℃(脱水花粉)、-50℃低温条件保存的桔梗花粉,随着贮藏温度的下降花粉生活力下降速度明显减慢,贮藏时间明显延长.     

百合花粉超低温保存方法研究

以“索邦”和“西伯利亚”百合为试材,研究了不同干燥时间和不同预处理温度及不同化冻方式对花粉超低温保存后百合花粉萌发率的影响.结果表明:不同干燥时间和不同预处理温度对超低温保存后花粉的萌发率有显著影响.与对照相比,2h干燥预处理(即花粉的含水量分别为7.67％和7.27％)后百合花粉的萌发率显著高于1、3、4h处理的;-20℃低温预冻处理后百合花粉的萌发率显著高于CK(室温)、0℃、-70℃处理的;超低温保存后40℃水浴化冻效果最佳.     

保存条件对西瓜花粉生活力的影响

西瓜花为半日花,西瓜花粉的生活力在田间条件下开花几小时后即完全丧失。为了延长花粉的生活力,以二倍体西瓜B99品种为试材,研究了不同保存条件对西瓜花粉生活力的影响,结果表明:常温干燥条件下可延长花粉保存时间;低温(4℃)干燥(RH25%)条件下保存花粉,花粉生活力4d内降低较慢,4d后降低稍快,但到第9天仍有1/3以上的花粉具有生活力;前8d的坐果率可达到自然状态(用新鲜花粉授粉)的73%,这在实践中完全可以利用,尤其是对4、5d之内的短期保存更有利用价值。     

不同贮藏方式下新疆5个杏品种花粉活力比较

正目的:通过对不同贮藏条件下5个杏品种花粉活力的测定,比较杏品种花粉活力,探索杏品种花粉长期保存的最佳贮藏条件。方法:用培养基法测定,伊力克大杏、克孜佳娜丽、大白油杏、大果杏和卡巴克玉吕克5个杏品种花粉在室温干燥(20℃)、室温黑暗干燥(20℃)、低温黑暗干燥(4℃)和低温黑暗冷冻干燥(-20℃)贮藏条件下花粉活力的变化。结果:杏     

不同干燥法与贮藏温度对玉兰花粉萌发的影响

以5～7a生玉兰为试材,研究了日晒干燥法、阴干干燥法、灯照干燥法、恒温干燥法4种干燥方法和室温、4、0、-20、-40、-80℃6个贮藏温度对玉兰花粉萌发的影响。结果表明:玉兰花粉采用阴干干燥法干燥优于日晒、灯照和恒温干燥法。阴干后的花粉分别在室温、4、0、-20、-40、-80℃贮藏10、20、30和40d,玉兰花粉的离体萌发率均降低。室温下,玉兰花粉的萌发率随贮藏时间的增加降低得最快,贮藏前(0d)玉兰花粉的萌发率为73.3%,至40d萌发率已降为0%。4和0℃条件下,花粉萌发率的降低速度相近。-40和-80℃花粉的贮藏效果最好,保存至40d时,花粉萌发率仍然在50%以上。     

不同贮藏方法对黄瓜花粉活力的影响

以"D0716"黄瓜植株为试材,研究了不同温度条件下黄瓜鲜雄花保存花粉、直接保存花粉和贮藏花蕾对花粉活力的影响。结果表明:黄瓜花粉活力随贮藏时间延长而降低;低温可以延长黄瓜花粉的寿命,但不利于黄瓜的开花和散粉;4℃下贮藏黄瓜鲜雄花花粉寿命比CK延长84h,且萌发率降低程度最小;直接保存花粉比鲜雄花保存花粉的花粉寿命短;与15℃相比,4℃贮藏花蕾的花粉活力保持的时间要长,但低温不利于开花散粉,所以在授粉前要将低温贮藏花蕾提前放在常温(25℃)一段时间以加速雄花的开放和散粉。     

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.