杂交玉米新品种‘黔单8号’高产栽培优化模式研究

采用四因素五水平二次通用旋转回归组合设计，研究‘黔单8号’的最佳播种密度和氮磷钾的施用量，初步建立了‘黔单8号’的产量与播种密度及氮磷钾施用量主要栽培因素的回归模型，并总结出‘黔单8号’在贵州山区产量获得777．80kg／667m^2的最优方案为：栽培密度在5014-5903株／667m^2，施氮量在38．28-45．72kg／667m^2，施磷量在138．8～151．2kg／667m^2，施钾量在37．73～42．27kg／667m^2。     

播期、密度及施N量对3个宽柄芥新品系经济性状的影响

采用正交试验设计18(37)，开展了播期、密度及施N量对3个宽柄芥新品系经济产量影响的研究。试验结果表明，品种和播期对产量影响表现为极显著；施N量和种植密度对产量影响表现为显著，最优高产处理组合为A2B2C3D1，即在重庆市涪陵区沿长江生态条件下，宽柄芥种植应选择中晚熟新品系DJ、播期为9月6日、种植密度为3500株/667 m2、施纯N量20 kg/667 m2，可获得高产。     

‘Q优6号＇水稻无盘抛秧免耕配套栽培技术研究

以杂交稻‘Q优6号’为试验材料,采用四元二次回归正交旋转组合设计和DPS分析的方法,研究了水稻无盘抛秧的配套栽培技术。结果表明：在免耕无盘抛秧试验条件下,‘Q优6号’稻谷目标产量在515kg／667m^2以上的优化农艺措施方案为种植密度为1．162万～1．238万株／667in。,施氮肥（纯N）11．693～12．307kg／667m^2,施磷肥（P2O5）9．249-9．984kg／667m^2,施钾肥（K2O）9．961～11．294kg／667m^2。     

施肥对药用长春花产量和生物碱含量的影响

对栽培的药用长春花施用氮肥和钾肥进行试验。结果表明：长春花在生长过程中对氮肥的需求量是比较高的，施氮肥15～30kg／667m^2可提高长春花茎叶产量7．5％～21．5％。但对茎叶中生物碱的含量影响不大；施钾肥1O-20kg／667m^2对长春花茎叶产量提高7．7％-12．O％，并对生物碱含量有一定的促进作用，超过这个用量茎叶生物碱含量减少。     

铜梁县超级稻高产栽培模式探讨

选用超级稻品种‘准两优527＇,采用L9（3^4）正交试验设计,研究不同叶龄移栽,不同施氮水平和不同栽植密度对水稻产量的影响,结果表明在遂宁组母质石骨子夹泥的中等肥力水平田块栽植中大穗型水稻品种,以每667 m^2植1.1万窝、3.5～5.5叶期移栽、在磷钾基础上每667 m^2用纯氮7～11 kg是获取水稻高产的栽培模式。     

杂交水稻金优554高产栽培数学模型研究

通过试验研究，建立了金优554产量与栽插密度及N、P、K施用量等栽培因素的数学模型，提出了金优554获得单产596．35kg／667m^2以上的优化方案。各栽培因素对产量的作用大小依次为施N量〉栽插密度〉施K量〉施P量。     

西瓜的施肥技术

西瓜的施肥量与土壤肥力、计划产量的高低有关，计划产量高。则施肥量要相应增加。据有关资料介绍，每增加1000kg产量，需氮4．6kg，磷(P205)3．4kg，钾(K20)4．0kg。在华北中等肥力土壤条件下，计划每667m^2 3000kg产量，则需氮7．56kg，磷2．43kg，钾8．58kg，除土壤中含有的氮、磷、钾外，每667m^2需补充氮11．12kg，磷5．72kg，钾10．97kg。     

梁平县地膜覆盖双季花生高产优化配方施肥试验

采用四因素三水平正交回归旋转组合设计，试验探讨在地膜覆盖条件下天府18号花生产量与种植密度、施肥量（N、P、K）间的关系，建立产量与各因素的优化数学模型：y=4111．8674＋45．7354X1＋53．2618X2＋57．12／Y3＋40．1058X4—18．9635X1^2—0．0460X2^2－17．5891X3^2－12．3483X4^2－0．0003X1X2＋0．0003X1X4－0．0752X2X4。确立了天府18号花生每公顷获得4025．18kg以上产量的高产栽培优化方案，即种植密度14．142万～15．714万株，46％尿素施用量244．24-292．50kg，12％过磷酸钙施用量415．00～586．00姆，600／0氯化钾施用量123．50～171．38kg。主要因子对产量的贡献大小为密度＞施氮量＞施钾量＞施磷量。     

不同施氮、钾肥量和种植密度对茭白产量的影响

采用二次通用旋转组合设计研究了不同施氮、钾量及种植密度对秋茭、夏茭的有效分蘖数、单茭重及产量的影响.结果表明,对秋茭施氮量16～18 kg/667 m2、施钾量17～18 kg/667 m2、种植密度0.7～0.8 m2/穴最为适宜;对夏茭施氮量控制在9～10 kg/667 m2,增施钾肥,种植密度维持在0.7～0.8 m2/穴较为适宜.     

寒地玉米高产栽培技术研究

通过对寒地玉米品种的对比试验，确定该地区最适玉米品种为德美亚1号和KX2030；以德美亚1号为材料，通过对玉米品种播期、施肥量、密度的比较试验，表明在该地区5月5日至5月10日之间为最佳播期，每667m^2施二胺12．5kg＋尿素12．5kg＋硫酸钾3．0kg为理想用肥水平，保苗在4500株左右为最佳密度。     

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.     

Cryopreservation of shoot apices of hawthorn in vitro cultures originating from East Asia

The objective of this study was to establish a cryopreservation protocol for hawthorn shoot apices (Crataegus pinnatifida Bge.). Cryopreservation was carried out via encapsulation–dehydration, vitrification, and encapsulation–vitrification on shoot apices excised from in vitro cultures. We began by showing that cold-acclimation enhanced the regrowth of cryopreserved apices from 10.0 to 65.5% in encapsulation–dehydration. We then decided that the encapsulation–dehydration method was an optimal cryopreservation method for hawthorn shoot apices in terms of its high recovery after cryopreservation as well as its ease of use compared with vitrification and encapsulation–vitrification. In encapsulation–dehydration, the protocol leading to optimal regrowth was as follows: after cold-acclimation at 5 °C in the dark for 2 weeks, excised shoot tips were pretreated for 24 h at 25 °C on hormone-free Murashige and Skoog [Murashige, T., Skoog, F., 1962. A revised medium for rapid growth and bioassays with tobacco tissue culture. Physiol. Plant. 15, 473–497] (MS) basal medium with 0.4 mol/L sucrose, then encapsulated and precultured in liquid MS medium with 0.8 mol/L sucrose for 16 h at 25 °C. Precultured beads were dehydrated for 6 h at 25 °C in the dessicator containing 50 g silica gel to a moisture content of 15.3% (fresh-weight basis) before cryostorage for 1 h. In addition, we examined the effect of adding glycerol to both the alginate beads and loading solution to enhance regrowth after cryopreservation in encapsulation–dehydration. In the present study, it was shown that adding 0.5 mol/L glycerol resulted in high regrowth percentages (82.5–90.0%) in four Crataegus species.     

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。