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1.
干巴菌(Thele-phoraganbajun)是一种外生菌根真菌,主要与云南松(Pi-nusyunnanensis)形成单轴二叉分枝和单枝的菌根。干巴菌的双校菌丝呈淡黄色和白色两种菌丝,分枝均稀少,菌丝分隔,菌丝具有锁状联合,有“H”型的菌丝细胞接合现象。  相似文献   

2.
柑桔高接换种不同组合生长结果表现四川省乐山市安谷镇果协从1990年以来,在全镇范围内陆续实施了大面积柑桔高接换种,实践表明,成土母质或土壤、基砧、中间砧不同,高接品种生长结果表现出较大的差异。现将在不同成土母质或土壤、基砧和中间砧上高接的不同品种接后...  相似文献   

3.
紫斑牡丹花粉发育的细胞形态学研究   总被引:13,自引:1,他引:12  
成仿云 《园艺学报》1998,25(4):367-373
紫斑牡丹花粉具二型性,正常花粉占84.3%,异常花粉占15.7%。正常花粉的发育可划分为单核小孢子早期、单核小孢子晚期、花粉第一次有丝分裂期、2-细胞花粉早期和2-细胞花粉晚期(成熟期)等5个时期;异常花粉在单核小孢子晚期开始分化,其中大部分逐渐停滞发育,少数(不超过1%)可在体内启动雄核发育途径,朝着形成孢子体的方向发展。  相似文献   

4.
1989-1993年,在甘肃苹果产区采集红星或元帅品种病果和无症状果实,逐果取果心组织分离,获得30余个真菌分离物,以链格抱(Alternariaalternata)出现率最高,占51.3%;其次为粉红单端孢(Trichotheciumroseum)、棒盘孢(Corymeumsp.)、节孢状镰刀菌(Fusariumarthrosporioides)、狭截盘多毛孢(Truncatellaangustata)等,依次占11.8%、12.0%、8.9%、7.9%。每个单果大多是只能分离出一种菌,少数出现2一3种菌。不同症状的果实,出现的真菌种类不同,霉心果以链格孢出现率最高,占60%-80%;心腐果中链格孢出现率显著较少,占10%-30%;而粉红单端孢、节孢状镰刀菌、棒盘孢、狭截盘多毛孢等5种菌的出现率较高,占7.8%-25.5%。用果心不带菌的果实人工接种,对12种分离物进行致病性测定看出,不同菌株之间致病力有明显差异,致心腐的病菌主要有5种,分别是粉红单端孢、棒盘孢、节孢状镰刀菌、狭截盘多毛孢和一种不产孢的浅色丝状菌。链格孢主要致霉心症状。混合接种试验表明,如有几种真菌进入果心,则致病性强的一种首先占据优势,?  相似文献   

5.
近年来,随着垦区盐潮土蔬菜栽培技术的推广和应用,广大菜农获得了较好的经济效益。但由于栽培土壤的特定环境条件,落后的施肥观念及肥水管理方法,使得土壤表层盐分积累严重,土质结构恶化,严重影响蔬菜的生长和发育。为此,通过大量的调查研究和生产实践,探讨垦区盐潮土盐害形成的原因及对蔬菜生产的影响,总结出垦区盐潮土(盐碱地)蔬菜栽培技术。1特定的土壤环境盐潮土的成土母质为海退的滨海沉积物,或是河口三角洲淤积物,或二者交错迭合,经人为垦荒利用,蓄淡洗盐,耕作施肥以后,逐渐形成具有一定生产能力的盐碱地。盐潮土呈…  相似文献   

6.
怎样用煤灰做肥料据测定,煤灰中一般含氮和磷(五氧化二磷,)都在0.2%左右,含钾(氧化钾)0.3%-0.5%,含钙(氧化钙)8.5%。粘土地施用煤灰,可增加土壤通透性,改善土壤的团粒结构和耕性;在盐碱地施用煤灰,可减轻土镶返碱,改良盐碱地。煤灰制肥有...  相似文献   

7.
不同母质荔枝园土壤养分比较研究   总被引:1,自引:0,他引:1  
荔枝生产一直存在着大小年结果现象 ,荔枝的高产稳产成为当前生产中亟须解决的问题。荔枝的生长发育和开花结果除受气候及管理水平影响外 ,土壤肥力也是一个关键因素。海南省荔枝栽种地土壤母质多样 ,不同成土母质荔枝园土壤养分状况不一 ,对施肥管理要求不同。为此 ,笔者对海南不同母质的荔枝园土壤取样分析 ,以了解不同成土母质荔枝园土壤养分的特点 ,为因地制宜进行果园土壤管理及科学施肥提供依据。1 材料与方法  供试土壤于 2 0 0 0年 8~ 9月分别取自发育于玄武岩、花岗岩和沙页岩的砖红壤荔枝园土壤。沿树冠滴水线下土壤按 0~ 4 …  相似文献   

8.
苹果新根内源多胺周年形成动态研究   总被引:8,自引:1,他引:7  
杨洪强  黄天栋 《园艺学报》1994,21(2):145-149
研究了苹果吸收根和延长根内多胺(精胺、亚精胺、腐胺)的周年形成动态。结果表明,两类新根中多胺总量1年内均有3次明显的形成高峰,分别出现在4月初、6月上和9月初;5-7月3种多胺变化最频繁;亚精胺和腐胺含量在两种根内均有4次高峰,吸收根内精胺含量有5个峰,延长根中有3个峰,两种新根内精胺含量最高,变化也最大。  相似文献   

9.
本文研究了干巴菌的分布及其在分布区内的植被类型,查清了干巴菌主要分布于针叶树林中,尤以云南松林内分布最多,但也分布于纯的栗树林中。通过对于巴菌生境中土壤微生物的分析,结果与宏观调查一致:其生长土壤较为贫瘠,是一种菌根菌。  相似文献   

10.
干巴菌担孢子多核现象的研究   总被引:1,自引:0,他引:1  
干巴菌(ThelephpragonbajunZang)是一种可食性菌根真菌,主要分布于中国云南中部地区。本文报道干巴菌振孢子的多核性及其担孢子在萌发过程中的多芽管现象。采用Giemsa'sStain及Nematoxylin等染色方法研究的结果表明:干巴菌担孢子具有单核、双核、三核、七核等多核性。并在担孢子萌发过程中发现与孢子多核性相对应的一个芽管,二个芽管、三个穿管、七个芽管等多芽管现象,产生真菌孢子多核现象原因,是由于孢子形成过程中,细胞核行为造成的。当担孢子形成过程中,二个单倍体核进行核配形成一个二倍体核,它再进行一次减数分裂,结果在担子中产生四个单倍体核,四个单倍体核随机进入担孢子后,造成多个核、一个核和无核孢子现象。另一种情况,是担孢子中一个核或多个核再行一次或多次减数分裂,从而产生了某些属种真菌的多核孢子。干巴菌担孢子的多核现象,属首次报道。  相似文献   

11.
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.  相似文献   

12.
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.  相似文献   

13.
多效唑对猕猴桃离体试管苗生长及内源激素的影响   总被引:18,自引:0,他引:18  
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。  相似文献   

14.
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.  相似文献   

15.
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.  相似文献   

16.
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.  相似文献   

17.
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.  相似文献   

18.
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.  相似文献   

19.
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.  相似文献   

20.
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.  相似文献   

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