日光温室番茄短季节高密度栽培适宜密度筛选试验

通过对不同密度下番茄产量及品质的变化分析,筛选出适宜2—5月番茄短季节高密度高品质栽培的适宜密度,从而为昌平地区草莓生产后期及空闲期提供一种全新的生产模式选择。结果表明:在2—5月短季节高密度无土栽培(留2穗果)模式下,667 m2定植量在8 000株时,番茄凯德6361的产量最高(6 390.5 kg),糖分含量最高(52.7 g/kg),是标准值的2倍以上(标准范围15~25 g/kg),糖酸比达到14.01,口感较好,较适宜鲜食生产选用;667 m~2定植量在10 000株时,番茄红素含量最高,达到127.735μg/g,单果质量为151.0 g,667 m~2产量显著高于对照处理,较适宜进行托盘包装后作为功能型产品销售。     

连栋温室短季节番茄岩棉栽培的适宜密度研究

本试验在北京市通州连栋温室内选择番茄为试材,进行短季节岩棉栽培试验。茬口安排为2月定植,7月拉秧。研究在温光资源丰富的环境下高密度种植的植株长势和单位面积产量情况。结果表明,在2.5株/m~2、3.75株/m~2、5.0株/m~23种种植密度条件下,番茄植株株高差异不显著,但5.0株/m~2的处理植株茎粗最大,分别比2.5株/m~2、3.75株/m~2高9.58%、9.87%,且有显著性差异;在单位面积产量方面,5.0株/m~2的单位面积产量达到6.82kg/m~2,分别比2.5株/m~2、3.75株/m~2高9.6%、18.1%,并且有显著差异。综合比较,在2～7月时间段内,增加番茄种植密度,有利于单位面积产量的提高。     

不同灌溉方式对北京春茬露地生菜的影响

为了探索适宜于北京春茬露地生菜的灌溉方式,以生菜品种"雷达"为研究对象,设置3个灌溉处理,以常规灌溉为对照,研究不同灌溉方式对生菜生长、品质和产量的影响。结果表明:常规灌溉处理的株高和叶片数显著低于微喷带和边缝式滴灌带处理;边缝式滴灌带处理的单方水产出最高,且其植株硝酸盐显著低于微喷带处理,维生素C含量要显著高于微喷带处理和常规灌溉处理,果实营养价值和安全性相对较高。综合考虑植株生长、品质、产量和单方水产出率等要素,边缝式滴灌带相对适宜春茬露地生菜的生产,其产量667m~2达到了2 797kg,单方水产出率达到31.3kg·m~(-3),单方水产出率比微喷带处理和常规处理分别高20.8%和233.0%。试验还得出了春茬露地生菜各生育时期的作物系数,能够为实现春茬露地生菜的高效生产提供一定的参考依据。     

丝瓜新品种寿研特丰一号、寿研特丰二号特征特性及配套栽培技术

<正>1选育过程丝瓜是我国南方地区夏秋季主要的瓜菜类品种,以其独特的食用和药用价值深受消费者欢迎。长期以来,寿光大棚丝瓜品种多为南方的露天品种,且品种繁杂,产量低。一般667m~2定植1700～2200株,产量为2500kg,水肥管理好者可达3000kg以上。上世纪90年代未,寿光将丝瓜进行日光温室种植,定植密度3000～3500株/666.7m~2,产量也     

大连地区冷棚西芹一年两茬高产高效栽培技术

近年来大连地区冷棚西芹栽培面积越来越大。春季一般在2月上旬育苗,4月下旬定植,7月份前后上市,此时为蔬菜供应淡季,售价及产量均较高;秋季在7月上旬育苗,9月初定植,11月下旬上市。667m2保苗8400株,收获时平均每株重1.2kg以上,667m2产量可达10000kg以上,一茬667m2收益在10000元以上,最高达25000元。现将冷棚西芹一年     

密度、苗龄和追肥对大棚甜椒生长、产量及经济效益的影响

为研究北方越夏茬大棚甜椒高产配套栽培技术,以甜椒"红美人"为试材,采用L16(43)正交实验设计,比较不同水平密度(667 m~2密度为3 000~3 900株)、苗龄(50~71d)、追肥(667m~2施肥0~40kg)处理对甜椒生长、产量及经济效益的影响。结果表明:影响甜椒不同性状的主导因子各不相同,苗龄对植株前期生长具有显著影响,对果实性状及产量影响不显著,57d苗龄最适于植株生长;密度及追肥量对单果质量、坐果总数、产量具有显著或极显著影响,单果质量最佳组合为667 m~2栽植密度3 300株、50d苗龄、追肥40kg),坐果数最佳组合为667m~2栽植密度3 600株、57d苗龄、追肥30kg。产量最佳组合为667m~2栽植密度3 600株、50d苗龄、追肥30kg。通过综合分析得出,该试验条件下甜椒获得最高产量及经济效益的组合为667m~2栽植密度3 600株、57d苗龄、追肥30kg。     

定植方式及定植密度对青花菜瑞绿6号制种产量及种子纯度的影响

为了增加瑞绿6号的制种产量及种子纯度,研究了不同定植密度(每667 m~2分别定植2 000、2 200、2 400、2 600株)和不同定植方法(隔株、隔行、隔垄)对瑞绿6号制种的影响。结果表明:青花菜瑞绿6号制种中,父母本应该严格采用隔株定植;每667 m~2定植2 400～2 600株最为合适,每667 m~2制种产量为25.7～25.9 kg,且种子纯度大于96%。     

不同种植密度对遵辣9号产量与经济效益的影响

为研究遵辣9号的较佳种植密度,采取随机区组设计,开展不同种植密度对遵辣9号产量与效益的影响研究。结果表明:随着种植密度的不断加大,遵辣9号产量成曲线变化趋势,峰值出现在2 500株/667 m~2,此时鲜椒产量达1 471.85 kg/667 m~2,比CK 2 000株/667 m~2高5.7%,比处理3 000株/667 m~2高9.5%,比处理3 500株/667 m~2高13.17%,比处理4 000株/667 m~2高34.76%,比处理4 500株/667 m~2高44.98%。2 500株/667 m~2时,经济效益达到最高,为5 298元/667 m~2,减去投入成本后,纯收入最高为2 208元/667 m~2,纯收入产出投入比最高为1∶0.715。结果表明,2 500株/667 m~2是遵辣9号较佳的群体结构和种植密度。     

不同播种期对水培生菜产量和品质的影响

以生菜品种绿领和弘农为材料,研究了春季不同播种期对水培生菜生长发育、产量和品质的影响。结果表明,不同播种期下生菜的产量和品质有显著差异,早播和晚播均降低生菜的产量和品质,播期为3月17日时产量最高,绿领和弘农分别为271.19 g/株和243.67 g/株;此播期的2个生菜品种VC含量也最高,且硝酸盐含量相对较低,表明选择适宜的播种期有助于提高生菜的产量和品质。     

不同种植密度对遵椒4号产量的影响

为进一步提高遵义县辣椒种植水平,以遵椒4号为材料,测试不同种植密度对遵椒4号产量及其构成因素的影响。结果表明,不同种植密度对遵椒4号的生育进程影响小,对其主要生物性状和经济性状均有不同影响,对产量构成因素影响显著,过稀过密都不利高产。遵椒4号种植密度为7200株/667m~2时产量最高,其干椒产量达276.8 kg/667m~2,且收益也达到最高,为3 187.8元/667 m~2。通过种植密度影响产量的数学模型计算,遵椒4号种植密度达到7 133株/667 m~2时,可实现其最高干椒产量256.2 kg/667 m~2。     

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 L-Arg on plasma content of endothelin and expression of c-fos mRNA in the left ventricle of rats with renovascular hypertensive hypertrophy

AIM:To study the effect of L-Arg on plasma content of endothelin (ET) and the expression of proto-oncogene c-fos mRNA in the left ventricle of rats with renovascular hypertensive hypertrophy. METHODS: The level of c-fos mRNA were measured by in situ hybridization. The ET in plasma were measured by radioimmunoassay. RESULTS:After eight weeks of treatment with L-Arg, the expression of c-fos decreased markedly (P＜0.01). The ET content in plasma also decreased significantly by L-Arg(P＜0.01).CONCLUSION: Plasma ET content and the expression of c-fos in the left ventricle of rats with renovascular hypertensive hypertrophy could be decreased by L-Arg administration.     

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.     

Compositional and Functional Properties of Saskatoon Berry and Blueberry

Abstract

Saskatoon berry (Amelanchier alnifolia Nutt., Rosaceae) and blueberry (Vaccinium corymbosum L., Ericaceae) are substantially equivalent in all characteristics that are important to the consumer, including fruit color, shape, size, nutrition, texture, and uses. In addition, both fruits are native to North America and they have practically identical historical uses and known health benefits. Their composition, processing, nutritional value and metabolism, intended uses, and levels of undesirable substances are compared.     

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.