渭北旱塬果园生草技术

果园生草技术是我国果园土壤管理中新兴起的一种制度。果园生草是果园土壤管理的一次大变革,它解决了土壤有机质多年短缺的难题,也开辟了利用生草来调控土壤中水分含量的节水农业这一新思路,同时也简化了果树栽培方面的许多管理环节,使生产绿色果品変成了现实。1生草技术发展趋势目前国内以生草技术为主要内容的果园土壤管理制度有自然生草制(图1)、人工种草制及覆草制三种类型。     

行间生草对甜柿果园土壤微生物和酶活性的影响

以甜柿品种"阳丰"为试材,采用自然生草和人工生草的方法,研究了不同生草处理对土壤微生物数量和酶活性的影响,以期为甜柿果园栽培管理中果园生草提供理论依据。结果表明:人工行间生草可以提高甜柿果园0～20、20～40、40～60 cm土壤细菌、真菌和放线菌数量,但不同草种对各个菌类数量的影响不相同。与自然生草相比,人工生草处理对甜柿果园0～20、20～40、40～60 cm土层土壤过氧化氢酶活性、土壤脲酶活性、土壤蔗糖酶活性和土壤磷酸酶活性有促进作用,但其效果因生草种类而存在明显差异。该研究表明生草可以改变甜柿果园土壤微生物数量和酶活性,建议甜柿果园栽培生产中应合理配置草种,优先推荐以林间组合为主,以保证土壤微生物和酶活性的同步均衡增加。     

河北省苹果园生草现状及土壤-树体-果实的综合效应

为明确河北省苹果园行间生草现状,探究草种适应性,为河北省果园生草栽培技术的推广与应用提供依据。采用调研的方法探究河北省果园行间生草的现状;在邢台市浆水镇富士苹果园,设置清耕、苜蓿、白三叶和自然生草4个处理,测定土壤有机质、无机氮、全氮、有效磷、速效钾、储水量和土壤酶活性等土壤性状,分析叶绿素、叶面积和新梢长等树体生长指标以及产量、果实品质。结果表明,河北省果园以清耕管理为主,生草园占31.96%,其中自然生草园占25.77%,人工生草园占6.19%;自然生草园草种选择更多样化;果农对生草认知缺乏且获知途径单一。自然生草显著提高0～20 cm和20～40 cm土壤有机质的积累,分别为15.46 g/kg和8.85 g/kg;苜蓿与白三叶显著增加了0～20 cm土层土壤无机氮、有效磷、速效钾含量,且对0～40 cm土层储水量有显著影响。白三叶与自然生草显著提高叶片叶绿素SPAD值,苜蓿与自然生草则显著增加了叶面积,苜蓿与白三叶显著增加了新梢长,连续6年生草老园叶绿素SPAD值(58.96)、叶面积(18.57cm²)以及新梢长(28.00 cm)均显著高于其他处理。苜蓿、白三叶与自然生草显著增产7.21%～13.40%。连续6年生草老园果实Vc(182.20 mg/kg)和可溶性糖(16.93%)显著高于各处理,可滴定酸(0.309%)显著低于清耕。河北省生草技术普及度低,行间种植苜蓿与白三叶能改善土壤性状、促进树体生长,改善果品品质、增加果品产出,因此推荐河北省苹果园种植豆科植物苜蓿和白三叶。     

豫西丘陵干旱区果园生草土壤培肥效应分析

以清耕为对照,研究分析了人工种植紫花苜蓿草与自然生草对果园土壤的培肥效果。结果表明:人工与自然生草均能提高土壤(0～30cm土层)有机质含量,且以表层土壤增加更为显著;人工与自然生草处理0～30cm土层土壤速效氮、速效磷和速效钾均有不同程度的提高,土壤微生物数量也有显著增加。表明生草能显著培肥土壤,在干旱区果园紫花苜蓿草的人工种植应大力推广。     

果园自然生草可利用的野生草种

<正>果园生草是现代化果园生产管理的一项重要环节,也是目前世界果树生产强国普遍采用的果园土壤管理模式,果园生草可以增加土壤肥力,改善土壤理化性质,保持土壤墒情,调节果园小气候,减少虫害的发生,降低生产成本,提高果品质量,还可以美化果园环境。果园生草通常有两种方法,一种是人工生草,即人工种植长毛野豌豆、鼠毛草、紫花苜蓿、高羊茅、黑麦草、白三叶等草种。另一种方法是自然生草,即利用果园原     

果园人工生草栽培管理技术

<正>果园生草对保持果园水土,促进土壤微生物活动,改良土壤理化性状,改善果园生态环境,增加天敌数量,控制害虫发生,促进果树生长发育,提高果实产量和品质等方面作用显著。果园生草栽培模式有全园生草、行间生草及株间生草3种。可人工种草和自然生草,其中人工种草由于选择了生长量大、营养丰富的草种,通常肥田效果更佳。     

管好用好果园野草

<正>果园生草的办法有人工生草和自然生草两种,我们提倡自然生草,即充分利用适合果园的野生草,因为这是一种投资少、见效快、简便易行的好办法。笔者对连续10年以上保留、利用野生草的果园进行过调查,认为生草园与清耕园相比较有如下优势:1)具有更好的保水能力。夏季高温期,生草园地面覆盖有草层,含水量明显高于清耕园。2)具有更好的排水能力。夏秋多雨季节,生草园中的草旺盛生长,可以吸收一部分土壤水     

果园半自然生草栽培

半自然生草就是在每年的生长初期,让果园自然生草,在生长中后期,割草覆盖树盘以控制杂草生长。坡地类型果园,在定植时一般修有半圆形“蜗牛坑”,当杂草长到30 cm左右时,从距地面 10 cm处割下,铺放在“蜗牛坑”内任其腐烂。6~8 月份杂草生长量大时,一般要割草2~3次,以保持果园生草高度不超过 30 cm。至生长末期,则任杂草自然死亡。半自然生草果园树盘区域土壤肥水状况与覆草果园相似。生草区土壤肥水状况略低于覆草果园,但明显高于清耕除草栽培的果园。连续3 a(年)以上半自然生草果园的土壤有机质含量为清耕除草果园的 1.73 倍,有效磷含量为…     

果园生草制是中国苹果产业转型升级的重要途径

分析了中国果园土壤现状,提出实现果树优质丰产对土壤条件的要求;针对目前中国果园土壤管理存在的问题,阐述了实行生草制的必要性、中国自然条件下果园生草制的原理及技术效果。     

柑橘园生草法栽培技术要点

生草法栽培，就是实行橘园生草，采用除草剂与人工割草相对合，或有计划地种植绿肥进行深翻压绿。实行以园养园的做法。它是目前柑橘园，特别是幼龄未封行柑橘园的一套较理想的土壤管理方法，也是一项省力化栽培技术。现将技术要点论述如下。１ 草种选择１．１ 优良草种的基本条件 进行果园生草栽培，首先要正确选择草种，这是确保果园生草栽培获得成功并取得良好效益的关键。生草栽培草种选择的基本条件是：①适应性强，要求对气候、土壤条件具有广泛的适应能力。②植株矮小，不影响果园通风透光和妨碍果园田间作业；根系浅，少与果树争夺…     

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.     

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.     

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.     

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.     

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.     

The effect of exposure on landscape scale soil surface temperatures and species distribution models

Species distribution models (SDMs) often use elevation as a surrogate for temperature or utilise elevation sensitive interpolations from weather stations. These methods may be unsuitable at the landscape scale, especially where there are sparse weather stations, dramatic variations in exposure or low elevational ranges. The goal of this study was to determine whether radiation, moisture or a novel estimate of exposure could improve temperature estimates and SDMs for vegetation on the Illawarra Escarpment, near Sydney, Australia. Forty temperature sensors were placed on the soil surface of an approximately 12,000 ha study site between November 2004 and August 2006. Linear regression was used to determine the relationship with environmental factors. Elevation was correlated more with moderate temperatures (winter maximums, summer minimums, spring and autumn averages) than extreme temperatures (summer maximums, winter minimums). The correlation (r ²) between temperature and environmental factors was improved by up to 0.38 by incorporating exposure, moisture and radiation in the regressions. Summer maximums and winter minimums were predominately determined by exposure to the NW and coastal influences respectively, while exposure to the NE and SW was important during other seasons. These directions correspond with the winds that are most influential in the study area. The improved temperature estimates were used in Generalised Additive Models for 37 plant species. The deviance explained by most models was increased relative to elevation, especially for moist rainforest species. It was concluded that improving the accuracy of seasonal temperature estimates could improve our ability to explain the patchy distribution of many species. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.