设施种植年限对土壤铵态氮、硝态氮及硝化强度的影响

为了解设施蔬菜种植年限对土壤矿质氮含量及硝化强度的影响及各指标间的相关关系,以露地菜田土壤(0年)为对照,以不同种植年限设施菜田土壤(5、10、15、20年)为供试土壤,分别测定其铵态氮含量、硝态氮含量及硝化强度,以明确设施蔬菜种植年限对土壤自身速效养分供应能力的影响,为不同年限设施菜田定点施肥管理措施的制定提供依据。结果表明,无论是露地栽培还是设施栽培,0～20 cm土层的土壤铵态氮含量、硝态氮含量和硝化强度均高于相同种植年限20～40 cm土层,且设施种植年限越长,矿质氮的表聚特征越明显。与露地菜田相比,相同土层各设施菜田土壤的矿质氮含量均显著提高,随种植年限的增加,呈先升后降的趋势,0～20 cm土层矿质氮含量(w,后同)于15年时达最大值513.45 mg·kg^-1,20～40 cm土层矿质氮含量于10年时达最大值353.21 mg·kg^-1。硝化强度与铵态氮含量呈显著正相关,除种植年限为15年的设施菜田外,其余设施菜田土壤的硝化强度均高于相同土层露地菜田土壤,以10年设施菜田最大。应减少设施菜田氮肥投入,并控制其硝化强度,避免蔬菜产...     

添加外源氮对不同年限设施土壤矿质氮含量的影响

以3个不同种植年限(0、13年和21年)的设施菜田土壤为研究对象,通过36 d培养试验,研究了添加不同外源氮条件下土壤铵态氮、硝态氮及矿质氮的含量,明确设施蔬菜种植年限和添加外源氮对土壤矿质氮含量的影响,以期为设施菜田减肥、高效施肥管理措施的制定提供参考依据。结果表明:在培养过程中,随设施菜田种植年限的增加,土壤铵态氮、硝态氮和矿质氮含量均表现为增加趋势,但施氮对土壤矿质氮含量的增加效果则随之减弱,种植年限为0、13年和21年的设施菜田土壤矿质氮含量在培养期间的最大增量分别为90.77、83.66 mg·kg^-1和74.03 mg·kg^-1,硝化速率常数随种植年限的增加而减小。而同一种植年限下,土壤铵态氮、硝态氮和矿质氮含量总体表现为随施氮量的增加而增加,且同一施氮量下,全部施用无机肥处理大于有机无机配施处理,硝化速率常数表现出相同的趋势。该研究可通过施氮量和肥料种类的变化来直接调控土壤矿质氮含量,以减少氮素损失。     

种植年限对设施菜田土壤pH及养分积累的影响

本试验以山东省寿光地区设施菜田为研究对象,分析了不同种植年限设施菜田土壤pH值以及有机质、无机氮、有效磷和有效钾含量状况。结果表明,寿光地区设施菜田各土层土壤pH值随着种植年限的增加而下降,与露地小麦土壤相比降幅达0.05～0.69个单位,其中尤以0～20 cm土层降幅最大,并且随着种植年限的增加,下层土壤pH值下降明显,种植10 a后20～40 cm土层土壤pH由8.67下降至7.99。0～20 cm土层土壤有机质随着种植年限的增加明显增加,1～3、4～6、7～9、≥10 a种植年限设施菜田土壤有机质与露地小麦土壤相比分别增加了6.1%、46.4%、66.5%、125.3%。土壤无机氮含量明显高于露地小麦土壤,但种植年限影响不大。各土层土壤有效磷和有效钾含量随着种植年限的增加显著增加,1～3、4～6、7～9、≥10 a种植年限设施菜田0～20 cm土层有效磷含量分别是露地小麦土壤的8.9、14.8、18.1、18.3倍,有效钾含量分别是露地小麦土壤的2.8、3.2、3.5、3.5倍。设施菜田各土层土壤pH值随种植年限的增加而下降,但与已有研究结果相比土壤pH值有上升趋势。     

不同种植年限设施蔬菜土壤理化性状的调查研究

我们调查了张家港市蔬菜主产区设施内不同种植年限0~20cm土壤耕作层的理化性状,研究随种植年限增加设施蔬菜土壤理化性状的变化特点。调查结果表明,设施内常年旱作土壤的pH值低于露地,其EC值、硝态氮及土壤有机质、速效钾、速效氮等养分含量均高于露地;连续旱作6年土壤的pH值低于连续旱作4年的土壤,其EC值、硝态氮、养分含量随着种植年限的增加而提高。     

设施条件下减量施氮对土壤硝态氮含量时空变化的影响

以辣椒品种"美园"为试材,通过田间试验和室内化验分析相结合的方法,研究了设施条件下不同处理(常规施肥、减氮15%、减氮30%、减氮45%、不施氮肥)对土壤硝态氮含量的影响。结果表明:随着土层深度的增加,土壤硝态氮含量逐渐降低,土壤0~40cm土层硝态氮含量波动较大,40~100cm土层硝态氮含量波动较小;随着氮肥施用量的减少,土壤硝态氮含量逐渐降低,减量施肥较常规施肥在不同土层深度土壤硝态氮含量波动小。随着采样日期的增加,土壤硝态氮含量在最终达到最小值,但是土壤硝态氮含量与采样日期不呈线性关系,0~40cm土层硝态氮含量波动较大,40~100cm土层硝态氮含量波动较小。     

高原设施土壤养分和蔬菜硝酸盐含量研究

以八一镇设施大棚为对象,研究了不同种植年限设施菜地土壤养分变化以及对硝酸盐累积、不同种类蔬菜硝酸盐含量的影响。结果表明:随着大棚使用年限的增加,土壤基础养分均出现了累积,硝态氮累积较为明显,3年棚龄的大棚中叶菜类蔬菜已出现重度硝酸盐污染,茄果类蔬菜硝酸盐污染较低。     

上海市奉贤区设施菜地土壤理化性状分析

测定了上海市奉贤区不同年限设施菜田土壤盐分含量、离子组成和肥力状况,并对土壤性状进行了分析。结果表明,棚龄2 a及以上设施大棚的盐分含量、电导率均显著高于1 a大棚,除HCO3-外,七大离子含量均显著提高;设施菜地土壤有酸化趋势,6 a及以上棚龄的设施菜田土壤pH值降至5.87,达到弱酸水平;随设施大棚种植年限增加,土壤有机质、全氮、碱解氮、有效磷含量呈上升趋势,特别是6 a及以上棚龄上升显著。     

微生物菌肥对设施番茄养分吸收与土壤氮磷累积的影响

以"朗庭"番茄为试材,采用田间试验方法,研究了增施微生物菌肥对番茄生长及土壤氮磷累积的影响,以期为设施番茄合理应用微生物菌肥提供参考依据.结果 表明:增施微生物菌肥能够提高番茄产量,增加氮磷养分吸收量,增加土壤硝态氮的累积,降低土壤有效磷向下移动.与常规施肥相比,含有枯草芽孢杆菌的微生物菌肥使番茄产量增加6.70％,氮素吸收量增加36.27％,磷素吸收量增加66.92％;收获期0～60 cm土层土壤硝态氮总累积量增加7.53％,有效磷总累积量降低26.70％,其中40～60 cm土层硝态氮累积量增加20.09％,有效磷累积量降低35.13％;同时增加根系在各土层的分布.     

设施菜地种植年限对土壤氨氧化微生物丰度和群落结构的影响

以种植3、5、7 a的设施菜地和露地蔬菜土壤为研究对象,采用荧光定量PCR和Illumina Miseq高通量测序技术,研究设施菜地种植年限对土壤氨氧化微生物丰度和群落结构的影响。结果表明:不同处理氨氧化古菌(AOA)丰度均大于氨氧化细菌(AOB),AOA/AOB值在17.33～39.16之间。随种植年限延长,AOA和AOB数量逐渐降低。种植年限对AOA和AOB群落结构和多样性有显著影响。二者多样性指数(Chao1指数、ACE指数和Shannon指数)均为种植3 a处理最大,随种植年限延长逐渐降低。在门水平上,AOA群落中奇古菌门为优势类群,AOB群落中变形菌门为优势类群。土壤pH、铵态氮和硝态氮是AOA群落结构变化的主要影响因素。综上,在设施蔬菜种植中,AOA在数量和群落多样性上占主导地位,对环境变化反应较敏感,可能是硝化作用的主要驱动者。     

不同种植年限蔬菜大棚土壤速效养分含量差异

以开封市郊区露地菜田和蔬菜大棚为研究对象,分析了不同种植年限下,露地菜田和蔬菜大棚之间的耕层土壤酸碱度以及速效养分的差异。结果表明:5年种植年限大棚土壤pH值比2年限大棚土壤降低了0.4个单位;5年种植年限大棚土壤碱解氮含量比露地种植高42.4%;2年限大棚土壤有效磷含量比露地土壤高4.6倍;土壤速效钾含量都达到国家一级标准,无明显差异;5年限大棚土壤有机质比露地土壤高13.6%。有机质含量与土壤碱解氮含量呈极显著正相关关系,与pH值呈显著负相关关系。     

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.     

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.     

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.     

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.     

多效唑对猕猴桃离体试管苗生长及内源激素的影响

多效唑（ＰＰ３３３）处理猕猴桃试管苗，降低了其生长强度；植株体内的ＧＡ３、ＩＡＡ和ＺＴ含量下降，ＡＢＡ的含量上升，乙烯释放率增加；并且能降低外源的ＧＡ３和ＩＡＡ促进生长的作用，而外源的ＧＡ３和ＩＡＡ又能不同程度地逆转多效唑的抑制作用，使植株恢复生长。     

Proteomic analysis between pathological scars and normal skin

AIM: To investigate and screen the sensitive proteins in the formation mechanism of pathological scars by comparing the results of differential proteomic analysis between pathological scars and normal skin.METHODS: Two-dimensional gel electrophoresis was used to detect the protein expression profiles in 8 keloid patients, 8 hypertrophic scar patients and 3 matched normal skin patients.The proteins that showed differential expression of over 4-fold change were cut and analyzed by MALDI-TOF/TOF mass spectrometry.RESULTS: A two-dimensional protein profiling comparison between pathological scars and normal skin was successfully established.On average, 2 978 spots in keloid, 2 975 spots in hypertrophic scar and 3 053 spots in normal skin were identified using gel analysis software.Compared with normal skin, there were totally 36 differentially-expressed proteins in keloid and hypertrophic scar identified from the spots of over 4-fold change, including 16 proteins in both keloid and hypertrophic scar (8 up-regulated and 8 down-regulated), 11 only in keloid (9 up-regulated and 2 down-regulated) and 9 only in hypertrophic scar (4 up-regulated and 5 down-regulated).CONCLUSION: Proteomic analysis can identify the proteins with variance of pathological scars versus normal skin, thus providing probable new clues to reveal the formation mechanism of pathological scars.     

Metallothionein inhibits homocysteine-induced proliferation of rat vascular smooth muscle cells

AIM:To investigate the effect of metallothionein(MT) on proliferation of rat vascular smooth muscle cells (VSMCs) stimulated by homocysteine and its mechanism. METHODS:VSMCs proliferation was measured by [³-H]-TdR incorporation, mitogen-activated protein kinase(MAPK)activity were determined by immunoprecipitation method, the intracellular contents of MT and malondialdehyde (MDA)were assayed by -hemoglobin saturation method and TBA reaction, respectively, and lactate dehydrogenase (LDH) leakage was measured by NADH oxidation. RESULTS:Hcy(10^-6-10^-4 mmol/L) stimulated [³-H]-TdR incorporation by the VSMCs in a concentration-dependent manner. Compared with control, [³-H]-TdR incorporation in VSMCs treated with 0.1 mmol/L Hcy was increased by 4.2 fold (P＜0.01). Meanwhile, Hcy enhanced MAPK activity, MDA formation and LDH release (P＜0.01)in a concentration-dependent manner. Treatment of VSMCs with MT alone did not change above parameters, compared with control. However, MT (10^-6-10^-4 mol/L)attenuated significantly Hcy-stimulated proliferation of VSMCs (P＜0.01)in a concentration-dependent manner. And MT inhibited obviously Hcy-induced activation of MAPK activity, MDA formation and LDH release. Preincubation of VSMCs with 0.5 mmol/L ZnCl₂ for 6 h induced an increase cellular MT content by 5.7-fold (P＜0.01). The MT-overexpressed VSMCs resisted Hcy-stimulating action on MAPK activity, MDA formation and LDH leakage (P＜0.01). CONCLUSION:These results show that MT has an inhibitory effect on Hcy-induced VSMCs proliferation, and that MT could inhibit Hcy-stimulated MAPK activity and lipid peroxidation.     

Coupling past management practice and historic landscape change on John F. Kennedy Space Center,Florida

Historic landcover dynamics in a scrubby flatwoods (Tel-4) and scrub landscape (Happy Creek) on John F. Kennedy Space Center were measured using aerial images from 1943, 1951, 1958, 1969, 1979, and 1989. Landcover categories were mapped, digitized, geometrically registered, and overlaid in ARC/INFO. Both study sites have been influenced by various land use histories, including periods of range management, fire suppression, and fire management. Several analyses were performed to help understand the effects of past land management on the amount and spatial distribution of landcover within the study sites. A chi-squared analysis showed a significant difference between the frequency of landcover occurrence and management period. Markov chain models were used to project observed changes over a 100-year period; these showed current management practices being effective at Tel-4 (restoring historic landscape structure) and much less effective at Happy Creek. Documenting impacts of past management regimes on landcover has provided important insight into current landscape composition and will provide the basis for improving land management on Kennedy Space Center and elsewhere.     

XBP-01 accelerated apoptosis induced by oxidized low density lipoprotein in vascular smooth muscle cells

AIM: Previous studies performed with XBP-01 in vitro indicated that XBP-01 could inhibit vascular smooth muscle cells from being transformed into foam cell and could eliminate the atherosclerotic plaque in C57BL/6J mouse. This experiment is to investigate its mechanism of eliminating plaques in vitro. METHODS: The cultured porcine artery smooth muscle cells incubated with XBP-01 of 0.1 mg/L for 24 h after preincubated with oxidized low density lipoprotein of 15 mg/L for 72 h in vitro. The samples were analyzed by fluorescence microscope, confocal microscope system and flow cytometry. RESULTS: Apoptosis was triggered by being incubated with oxidized low density lipoprotein and this process was accelerated additionally by being incubated with XBP-01. CONCLUSION: XBP-01 can be effective in eliminating atherosclerotic plaque by accelerating the process in which oxidized low density lipoprotein induced smooth muscle cell apoptosis.