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1.
以荒漠植物骆驼蓬为试材,采用室内变温光照培养的方法,研究了不同温度和盐胁迫及其互作对荒漠植物骆驼蓬种子萌发与幼苗生长的影响,以期探讨骆驼蓬种子萌发的最适温度和对盐胁迫的耐性。结果表明:温度和盐胁迫及二者的交互作用对骆驼蓬种子的萌发率、萌发速率、萌发势、幼苗芽长和根系均具有极显著影响(P<0.001)。骆驼蓬种子萌发率为30℃/15℃和35℃/20℃下最大,显著高于20℃/5℃或25℃/10℃(P<0.05);在30℃/15℃和35℃/20℃下,随着盐分增加,骆驼蓬幼苗芽长均表现为先增大后减小的趋势,表明在较高的温度下,50 mmol·L-1盐分更为显著地促进了骆驼蓬幼苗的生长;在所有温度条件下,随着盐分增加,骆驼蓬幼苗根长先增大后减小,在较高的温度下,100 mmol·L-1盐分更为显著地促进了骆驼蓬幼苗的生长。因此,幼苗根长和芽长对盐分与温度处理的响应不同。  相似文献   

2.
以荒漠严酷环境下植物种子适应性为科学问题,运用生理生态学原理,以采自不同生境的5个梭梭种群的种子为试材,在实验室模拟基础上,研究了梭梭种子萌发对干旱和盐分胁迫的响应规律。结果表明:在PEG溶液和盐溶液中,来自不同生境梭梭种群的种子其萌发率均随水势的降低而下降,分别到-2.26MPa和-4.15MPa时,所有种群梭梭种子萌发率均接近于零。在水势相等的情况下,所有种子的萌发均受到NaCl和等渗PEG溶液的抑制,并且等渗NaCl溶液对梭梭种子萌发的抑制程度要显著小于PEG溶液,说明渗透胁迫是影响梭梭种子萌发的主要因素。当解除盐胁迫后,梭梭种子恢复萌发率较高,表现出一定程度的高盐诱导休眠现象。水势相等条件下,PEG溶液中恢复萌发率低于NaCl溶液中恢复萌发率,表明离子效应对梭梭种子的影响要小于渗透胁迫。可见,梭梭种子萌发对盐分和干旱胁迫适应性强,是该种群恢复和保育的基础。  相似文献   

3.
以神香草种子为试材,采用滤纸培养皿法,研究其在不同浓度盐(NaCl、NaHCO3、Na2CO3)溶液、聚乙二醇(PEG 6000)溶液中的萌发特性,测定发芽率、发芽势、发芽指数等指标,并通过相对发芽率与各处理浓度建立的函数方程确定其种子的耐受性,以期为盐碱地区神香草的应用提供参考依据。结果表明:1)随着盐胁迫的增强,神香草种子的发芽率、发芽势和发芽指数均呈下降趋势,萌发起始时间逐渐延迟,发芽速率减慢。2)神香草种子对盐胁迫具有一定适应性,但不同盐溶液对神香草种子萌发的抑制效果具有差异性,神香草种子对中性盐胁迫的耐受性较强,对碱性盐胁迫较敏感。3)神香草种子在轻度干旱条件(PEG 6000 5 g·L-1)下发芽率、发芽势和发芽指数升高,随着PEG 6000溶液浓度的增大,神香草种子发芽起始时间推迟,各项指标呈下降趋势,种子的萌发表现出低促高抑的现象。  相似文献   

4.
童家赟  蓝天  任肖湘 《北方园艺》2016,(11):151-154
以酸浆种子为试材,分别采用浓度为0%~25.0%的PEG-6000模拟干旱胁迫,同时用0~150mmol·L~(-1) NaCl溶液模拟盐分胁迫,分别考察酸浆种子的抗旱和抗盐萌发特性。结果表明:随着PEG浓度增加,酸浆种子萌发延迟,且发芽率、发芽势和发芽指数均呈现明显下降趋势,PEG达25.0%时,酸浆种子没有萌发;临界胁迫浓度C_(50)为12.3%,高于番茄种子C50(8.0%~10.8%)。随着NaCl溶液浓度升高,酸浆种子的发芽率、发芽势、发芽指数也呈下降趋势;浓度达到150mmol·L~(-1)时,种子发芽率比对照组降低43.0%,萌发种子不能发育为正常幼苗;其C50为107.0mmol·L~(-1),低于向日葵种子的C_(50)(258.0mmol·L~(-1))。  相似文献   

5.
谭勇  刘雨婷  汝梅  谢凤凤  纪薇  韩凯 《北方园艺》2019,(11):112-116
以中药材知母种子为试材,采用聚乙二醇(PEG)干旱胁迫和混合盐胁迫的方法,研究知母种子在胁迫条件下的发芽势、发芽率以及胚根与胚芽长等生长性状指标,以期为知母人工栽培提供科学依据。结果表明:随着PEG浓度和NaCl与NaHCO3(1∶1)混合溶液浓度的增加,知母种子萌发均受到抑制,种子发芽势、发芽率、胚芽与胚根长度与直径都与之呈显著的负相关。PEG不同浓度梯度胁迫下,知母种子发芽势由16%降至4%,发芽率由80%降至52%,且知母种子萌发的致死浓度为15%;NaCl与NaHCO3(1∶1)混合溶液胁迫下,知母种子发芽势由16%降至6%,发芽率由80%降至14%,且知母种子萌发的致死浓度为1.20%。知母种子有一定的耐干旱及耐盐胁迫能力。  相似文献   

6.
研究了盐胁迫对辣椒种子萌发的影响及外源Mn^2+对盐胁迫的缓解作用。结果表明:盐胁迫对辣椒种子婚萌发具有抑制作用,随着盐浓度的增大,种子发芽率、发芽势和发芽指数均下降;在盐胁迫下,一定浓度的外源Mn^2+对盐胁迫具有一定的缓解作用,可增强辣椒种子对盐胁迫环境的适应性。  相似文献   

7.
盐胁迫对罗布麻种子萌发及幼苗生长的影响   总被引:3,自引:0,他引:3  
研究了不同浓度盐胁迫对罗布麻种子萌发及幼苗生长的影响。结果表明:对照及盐浓度为20%条件下种子萌发率最高;随着盐胁迫增加,SOD、POD活性及脯氨酸含量先增大后减小,在盐浓度60%处达到最大值;MDA的含量先减小后增大,在40%处达到最小值。表明一定浓度的盐胁迫可以促进罗布麻幼苗的生长,种子萌发以无盐及低盐环境最好。  相似文献   

8.
以大穗结缕草为试材,研究了光照/黑暗、温度、盐胁迫和干旱胁迫对大穗结缕草种子萌发特性的影响。结果表明:种子萌发为非需光种子,种子萌发最适温度范围为25~30℃;当NaCl浓度为100mmol·L~(-1)时,大穗结缕草种子最终萌发率与对照无显著差异,但种子发芽势和活力指数与对照有明显差异。当浓度为150~200mmol·L~(-1)时,显著抑制大穗结缕草种子的萌发。种子耐盐临界浓度和极限浓度分别为144.12、244.12mmol·L~(-1);随着干旱胁迫程度的增加,萌发进程所用时间增长,最终萌发率也显著下降,50g·L~(-1) PEG模拟干旱胁迫对种子萌发无显著影响,种子的耐旱临界浓度和极限浓度分别为90.95、155.05g·L~(-1)。综上所述,大穗结缕草种子在萌发期表现出一定的抗盐性和抗旱性。  相似文献   

9.
以呼和浩特地区引种的铃铛刺种子为试材,采用不同浓度的NaCl溶液(4、8、12、16、20 g·L-1)和 PEG-6000溶液(5%、10%、15%、20%、25%)模拟盐旱胁迫方法,研究盐旱胁迫下铃铛刺种子的萌发特性,以期为铃铛刺在干旱半干旱地区用于改良盐碱土及生态修复提供参考依据.结果表明:随盐胁迫程度的增大,铃铛刺种子的萌发率、萌发势呈先上升后下降的趋势,萌发指数、活力指数、胚根胚芽长随NaCl浓度的升高呈下降趋势;干旱胁迫下,各指标均随PEG-6000溶液浓度的升高而降低,低浓度(5%)对种子萌发抑制作用不明显;NaCl溶液和PEG-6000溶液浓度分别为20 g·L-1和25%时,铃铛刺种子的萌发率为54.67%和25.33%,未达到完全抑制其萌发的盐旱阈值,经引种的铃铛刺种子在萌发期仍具有较高的耐盐、耐旱特性.  相似文献   

10.
野生花卉紫花补血草种子萌发特性研究   总被引:1,自引:0,他引:1  
本试验研究了野生花卉紫花补血草的种子萌发特性.研究表明紫花补血草的种子微小,种皮浅褐色,有光泽,纺锤形,略侧扁,长约2.16mm,最宽处宽约0.86mm,最厚处厚约0.64mm,千粒重仅为1.023±0.016g.紫花补血草的种子萌发的适宜温度是20~30℃,不受光照影响,为光中性种子.紫花补血草虽然为盐生植物,但种子萌发对盐胁迫仍非常敏感,当溶液中单盐(NaCl)浓度达到0.1mol/L或含有20%海水时,紫花补血草种子的萌发即可受到明显抑制.  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.
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.  相似文献   

14.
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   

15.
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   

16.
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   

17.
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   

18.
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   

19.
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   

20.
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   

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