红实美草莓试管苗瓶外生根的研究

以红实美草莓试管苗为材料,研究了试管苗大小、基质、环境条件对试管苗瓶外生根的影响,并与瓶内生根相比较.试验结果表明,在温度23～27℃、湿度85%、光照为半遮光条件下7 d后,3.0～4.0 cm大小的试管苗在草炭:煤渣(1:1)基质中瓶外生根效果最好,生根移栽成活率98.6%,平均生根数7.8条/株;与瓶内生根相比,不仅降低了生产成本,而且还能缩短快繁时间28 d.     

观赏羽扇豆试管苗移栽成活率的影响因素研究

为了完善观赏羽扇豆离体快繁体系,从试管苗生根培养天数、不定根数量、练苗天数、移栽基质和空气相对湿度多方面进行了试管苗移栽技术研究。结果表明:在生根培养基上培养30~40 d,不定根数量大于6条的健壮苗是保证移栽成活的基本条件;试管苗先在温室条件下练苗3 d,移栽后前15 d控制相对空气湿度在90%~100%可显著提高移栽成活率;移栽基质为泥炭土∶珍珠岩∶河沙=1∶1∶1时,移栽成活率可达85.6%。     

笃斯越橘组培苗瓶外生根和移栽条件研究

以笃斯越橘优系SL-1组培苗为试材,研究光照时间、空气相对湿度和栽植时期对其瓶外生根的影响;以瓶外生根苗为试材,探讨移栽基质和不定根数量对其移栽成活率的影响。研究结果表明:笃斯越橘SL-1组培苗瓶外生根的最佳环境条件为最高温度22~25℃,空气相对湿度80%,每天光照时间8~10 h,4—5月栽植瓶外生根数量多,生根率可在80%以上;生根苗移栽的最佳基质是草炭土∶苔藓为2∶1,选用8条根以上苗,移栽成活率在95%以上。     

‘薄雾’蓝莓试管苗室内瓶外生根试验

以蓝莓品种‘薄雾’(‘Misty’)为试材,开展基质类型、生根营养液浓度、生根剂种类及浓度对蓝莓试管苗室内瓶外生根的影响研究。结果表明,以1 000 m L透明塑料盒为生根容器,以珍珠岩为生根基质,添加经煮沸灭菌的低浓度生根营养液(1/6WPM),营养液中加入2~3 mg/L IBA,取蓝莓试管苗扦插于其中,在室内继代培养条件下,插后21 d生根率在70%以上,插后40 d生根率在95%以上,根系均为短粗的白色须根,数量多,苗木长势健壮,且操作简单,炼苗移栽管理方便、易成活。     

月季试管苗生根的形态解剖学观察

以月季无根试管苗为材料,进行瓶内和瓶外生根试验,研究了试管生根苗和瓶外生根苗的解剖构造差异,并分析了二者解剖特征与其生境的关系。     

广东地区蓝莓试管苗移栽关键技术研究

以南高丛蓝莓品种比洛克西和兔眼蓝莓品种顶峰的试管苗为材料,研究了影响广东地区蓝莓试管苗移栽的关键条件,包括基质、光照、移栽时期、苗规格和生根剂处理等。结果表明:2种蓝莓试管苗宜在透光率30%遮阳网的遮光条件下移栽,基质选用泥炭土+河沙(2∶1,V/V),11月至翌年4月可在塑料大棚内移栽,其中3—4月移栽的试管苗生长表现最好;在试管苗扦插生根试验中,插条长度以2~4 cm为宜,1 000 mg/L ABT处理比洛克西试管苗、1 500 mg/L ABT处理顶峰试管苗生根效果最好。     

切花非洲菊瓶外生根技术与移栽基质的筛选

以切花非洲菊“太阳风”的无根试管苗为试材,以蛭石、珍珠岩∶草炭=2∶1、珍珠岩∶草炭=1∶1为基质,进行了不同激素种类和浓度的瓶外速蘸微扦插试验,25 d后调查移栽试管苗的叶片数、生根条数、根长3个指标.结果表明:各生长激素处理均促进了根的发生,各处理间的平均根条数存在极显著性差异,根长存在不同程度的显著性差异而叶片数没有显著性差异.根据试管苗根系的状况,筛选出蛭石为较适宜的基质,IBA 500 mg/L+NAA 500 mg/L为最适宜的激素处理,其次为IBA 500 mg/L.     

葡萄试管苗移栽技术

一、影响试管苗移栽成活的诸因素 葡萄试管苗的移栽,是葡萄幼苗由弱光、恒温、湿度近饱和及半异养型的状态转移至自然条件及自养型状态的过程,这一过程诸因素中,光照、湿度、苗龄、移栽基质是决定试管苗移栽成活的关键。本试验通过设置不同的处理,获得有关参数,经综合分析,以确定试管苗移栽的最适条件。 (一)光照强度与试管苗移栽成活:试管苗在瓶内为半异养型,其碳素来源除靠自身较弱的光合作用获得外,主要由培养基中摄取。试管苗由瓶内移至瓶外,其生理性状转化为完全自养型,光照是必要条件。采用光照强度为2400 Lx的处理,成活率明显高于13…     

薄荷试管苗练苗移栽技术

对薄荷试管苗驯化移栽技术及其影响因素进行了研究,总结出了薄荷组培试管苗练苗前后的一系列管理技术。介绍了薄荷试管苗练苗的最佳状态以及移栽技术,包括基质选择、定植方法和栽后护管等方面内容。结果表明:根系正常且经过10d的生根培养+室内驯化3d+开瓶练苗3d的试管苗,移栽到珍珠岩、细沙配比为2∶1的基质上,按照逐渐控水、增光、降温的原则进行管理,易通过练苗阶段,移栽成活率可达90%以上。     

蓝莓组培苗快繁技术研究

为提高蓝莓组培苗扩繁倍数和炼苗生根成活率,开展组培瓶内芽叶增殖、瓶外生根炼苗一体化方面的研究,为蓝莓进行组培快速繁育创造基础条件。     

Ergebnisse der Leistungsprüfungen der Süßkirschensorte ‚Stella‘ auf Gisela- und Weiroot-Unterlagen in Bulgarien

Zusammenfassung Die Leistungsprüfungen wurden im Zeitraum 1997 bis 2003 mit den Unterlagen Gisela 4 und 5, den Klonnummern 195/20 und 497/8 aus der Gisela-Serie sowie Weiroot 10, 13, 53, 72 und 158 durchgeführt. Dabei dienten Sämlinge von P1 (bulgarische Selektion aus Prunus mahaleb) als Kontrolle. Alle Unterlagen waren mit der Sorte Stella veredelt und im Dezember 1996 in der Versuchsanlage der Agraruniversität in Plovdiv, Bulgarien, im Abstand von 6 m×4,5 m gepflanzt worden. Dabei erfolgte ein Pflanzschnitt. Nach Abschluss der natürlichen Kronenentwicklung wurde jedes Jahr ein Winterschnitt vorgenommen. Der Boden wurde durch mechanische Bearbeitung offen gehalten und nach dem 4. Standjahr wurden die Baumstreifen mit Herbiziden behandelt. Die Wasserversorgung erfolgte durch eine dem natürlichen Gefälle folgende Überflutung, allerdings nicht immer zum optimalen Zeitpunkt, da keine eigene Wasserquelle zur Verfügung stand.Basierend auf den Ergebnissen bis zum Anfang des 7. Standjahres können die untersuchten Unterlagen in zwei Gruppen differenziert werden: starkwüchsig—Weiroot 10, P1 und Weiroot 13; mittelstarkwachsend bis schwachwüchsig—Gi 497/8, Gisela 4, Weiroot 53, Weiroot 158, Gi 195/20, Weiroot 72 und Gisela 5. Letztere zeichnete sich durch besondere Schwachwüchsigkeit aus. Die meisten Wurzelschosser bildeten Gisela 4, Weiroot 10 und Weiroot 13. Weiroot 53, Weiroot 72 und Weiroot 158 entwickelten deutlich weniger und P1, Gisela 5, Gi 195/20 sowie Gi 497/8 keine Wurzelschosser. Den frühesten Blühbeginn induzierte Gisela 4. Die anderen Unterlagen führten, in Abhängigkeit von den Temperaturbedingungen des jeweiligen Jahres, zu einer Verspätung der Blüte: P1 und Weiroot 10 um 1–2 Tage; Gi 497/8, Weiroot 13 und Weiroot 158 um 2–4 Tage; Weiroot 72 um 2–7 Tage; Gi 195/20 um 3–6 Tage; Weiroot 53 um 3–8 Tage und Gisela 5 um 3–10 Tage. Die Reifezeit der Früchte war bei den Bäumen auf Gisela 5 im Vergleich zu den anderen Varianten um 2–3 Tage verspätet. Gisela 5, Weiroot 72 und Gisela 4 induzierten bei der aufveredelten Sorte die höchsten Ertragsleistungen, P1 die geringsten. Bei den Bäumen auf Gisela 5 war die Fruchtgröße geringer als bei den anderen Unterlagen. Bäume auf Gisela 5 brauchen intensive Pflege. Nur wenn alle Produktionsfaktoren und kulturtechnischen Maßnahmen optimiert werden, kann das hohe Ertragspotenzial dieser Unterlage ausgeschöpft werden.     

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.     

Effects of radiation from 188Re on smooth muscle cell proliferation

AIM: Although endovascular radiotherapy inhibits neointimal hyperplasia, the exact alterations induced by β-particles irradiation remain to be elucidated. The objective of this study was to investigate the ability and the cellular mechanism of local β^-particles emission from ¹⁸⁸Re to inhibit vascular smooth muscle cells (SMCs). METHODS: The SMCs in vitro were irradiated by ¹⁸⁸Re with single doses of 2.6 Gy-25.8 Gy. The effects of β-particles on SMCs, such as effective irradiate doses, the period of inhibition for SMCs proliferation, the changes of cell proliferation rate and DNA synthesis rate, cell cycle progression and related gene expression, were investigated by cell count, [³H]-TdR incorporation, cell cycle progression analysis, cell viability and immunocytochemistry, respectivecy. RESULTS: β-particles irradiation with dose of 5.2 Gy could inhibit significantly SMCs proliferation. At dose of 20.6 Gy DNA synthesis inhibitory rate was 92%, SMCs proliferation rate was only 3%. Renoval of ¹⁸⁸Re did not abolish the inhibitory effects of β-particles on SMCs proliferation. The expression of P53 was up regulation and PCNA was down regulation after irradiation. CONCLUSION: β-particles from ¹⁸⁸ Re was significantly effective and permanent in inhibiting SMCs proliferation, and inhibitory effect was in dose-dependet manner ED50was 5 Gy, the best dose to inhibit SMCs proliferation was 20 Gy. β-particles irradiation induced SMCs to occur G₀/G₁ arrest, damaged the ability of SMCs reproliferation and led to cell clonogenic death. P53 and PCNA had regulatiory effects on SMCs proliferation after β-particles irradiation.     

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.     

Effect of puerarin on pulmonary arterioles wall collagen metabolism of chronic hypoxia hypercapnia rats

AIM:To investigate the effect of puerarin on pulmonary vessel collagen metabolism in pulmonary hypertension rats induced by chronic hypoxia and hypercapnia.METHODS:Collagen Ⅰ, Ⅲ and their mRNA were observed in pulmonary arterioles by the technique of immunohistochemistry and in situ hybridization.RESULTS:① Light microscopy showed media thickness of pulmonary arterioles was much higher in HH(hypoxic-hypercapnia) group than that of NC(normal control) group, and, vessel cavity turned more straiter in HH group than that of NC group.However, the damage of pulmonary arterioles in HP(hypoxic-pueratin) group was much slighter than that of HH group. ② The levels of plasma ET-1 and lung homogenates Hyr were much higher in HH group than those of NC group(P＜0.01), and lower in HP group than HH groups(P＜0.01).Plasma NO content in group HH was lower than that of group NC(P＜0.01), it was higher in group HP than that of group HH(P＜0.01).③Expression of collagen Ⅰ and collagen Ⅰ mRNA in pulmonary arterioles were significantly higher in HH groups than those of NC group (P＜0.01), and they were lower in HP group than those of HH group (P＜0.01).Expression of collagen Ⅲ and collagen Ⅲ mRNA showed no difference among three groups(P＞0.05).CONCLUSION:Puerarin inhibited the deposition of collagen and improved pulmonary vessel remodeling.     

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.     

Multi-scale landscape and seascape patterns associated with marbled murrelet nesting areas on the U.S. west coast

Habitat for wide-ranging species should be addressed at multiple scales to fully understand factors that limit populations. The marbled murrelet (Brachyramphus marmoratus), a threatened seabird, forages on the ocean and nests inland in large trees. We developed statistical relationships between murrelet use (occupancy and abundance) and habitat variables quantified across many spatial scales (statewide to local) and two time periods in California and southern Oregon, USA. We also addressed (1) if old-growth forest fragmentation was negatively associated with murrelet use, and (2) if some nesting areas are more important than others due to their proximity to high quality marine habitat. Most landscapes used for nesting were restricted to low elevation areas with frequent fog. Birds were most abundant in unfragmented old-growth forests located within a matrix of mature second-growth forest. Murrelets were less likely to occupy old-growth habitat if it was isolated (> 5 km) from other nesting murrelets. We found a time lag in response to fragmentation, where at least a few years were required before birds abandoned fragmented forests. Compared to landscapes with little tono murrelet use, landscapes with many murrelets were closer to the ocean's bays, river mouths, sandy shores, submarine canyons, and marine waters with consistently high primary productivity. Within local landscapes (≤ 800ha), inland factors limited bird abundance, but at the broadest landscape scale studied (3200 ha), proximity to marine habitat was most limiting. Management should focus on protecting or creating large, contiguous old-growth forest stands, especially in low-elevation areas near productive marine habitat. This revised version was published online in July 2006 with corrections to the Cover Date.     

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.