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1.
大白菜小株采种种株的光合特性 总被引:6,自引:2,他引:4
以大白菜‘鲁白8号’两亲本为试材研究小株采种种株的光合特性,结果表明:种株功能叶片光合速率为CO210~16μmol·m-2·s-1;最大光合速率出现于开花期;种株叶片光合速率日变化常呈双峰曲线,中午降低;单叶光合能力大小受叶龄叶位影响显著;盛花期种株的光补偿点和光饱和点分别为25~32μmol·m-2·s-1和950~1000μmol·m-2·s-1,CO2补偿点和饱和点分别为55~60μL·L-1和1200~1400μL·L-1;气温高于30℃或叶片相对含水量低于77%时光合速率下降,轻度水分胁迫下为气孔限制,严重水分胁迫下为非气孔限制;叶片、茎枝、角果均具有同化固定CO2能力,以叶片最强,茎枝最弱,茎枝和角果分别为叶片的11%~12%和20%~40%。 相似文献
2.
温度对生姜叶片光合特性的影响 总被引:7,自引:0,他引:7
生姜产品形成期叶片光合最适温度为25℃,此温度下光合速率和表观量子效率最高。光合速率在一定范围内随光量子通量密度和CO2浓度升高而增加。生姜叶片的光合作用光补偿点在25~69μmol·m-2·s-1之间,随叶温升高而升高,且叶温越高上升幅度越大;光饱和点为642~867μmol·m-2·s-1,在15~25℃范围内随叶温升高而升高,超过25℃,则随叶温升高而下降。CO2补偿点和饱和点分别为25~72μL/L和1343~1566μL/L,均随叶温升高而增加,且高温条件增加幅度大。 相似文献
3.
阿月浑子光合特性及其影响因子的研究 总被引:46,自引:4,他引:42
阿月浑子叶片光合速率日变化呈双峰曲线, 最高峰在11 时, 次峰在15 时, 中午有明显的“午休”现象; 季节变化亦呈双峰曲线, 最高峰在6 月, 次峰在8 月;6 月份枝条中部叶片光合速率大于顶部和下部叶片。光合作用的光补偿点和饱和点分别为51 μmol·m - 2·s- 1 和1 600 μmol·m - 2·s- 1 , CO2 补偿点和饱和点分别为136 μL/L 和830 μL/L; 光合作用的最适温度为30 ℃, 最适土壤相对含水量为70% , 灌水临界期的土壤相对含水量为30 % ~35% 。 相似文献
4.
低温胁迫对温州蜜柑光合作用的影响 总被引:47,自引:4,他引:43
低温处理使温州蜜柑叶片的气孔导度、净光合速率、光合表观量子效率及光合作用的光饱和光强和CO2饱和浓度降低,细胞间隙CO2浓度、光补偿点和CO2补偿点提高。虽然10℃处理植株数小时后即出现光合速率下降,但叶绿素荧光测定结果显示,只有在3℃低温处理后,反映光系统Ⅱ光化学效率的Fv/Fm比值和T1/2才有较明显下降,而F0则明显升高。低温在30~40μmol·m-2·s-1弱光下对光合的影响明显大于黑暗下。 相似文献
5.
土壤水分胁迫对大蒜光合特性的影响 总被引:16,自引:1,他引:15
研究了土壤水分胁迫对抽薹期‘苍山蒜’光合作用的影响。结果表明,在土壤水分正常条件下,大蒜光补偿点为79umol.m^-2.s^-1,饱和点为968umol.m^-2.s^-1;CO2补偿点为86uL.L^-1,饱和点为1450uL.L^-1。水分胁迫使大蒜的光合速率、光饱和点和CO2饱和点降低,光补偿点和CO2补偿点升高。 相似文献
6.
黄瓜单个叶片光合特性研究 总被引:62,自引:2,他引:62
系统测定了19个春季露地和冬季温室黄瓜壮龄叶片光合速率及其日变化,结果表明,在露地栽培条件下,大多数品种、杂交种和品系光合速率分布在CO220-30μmol.m^-2.s^-1之间。冬季温室栽培的长春密刺的光合速率远较露地栽培时低。无论温室还是露地栽培,黄瓜壮龄叶片光合速率日变化均呈双峰曲线型,有明显“午休”现象。光照强度、CO2浓度、温度及土壤湿度等外界环境条件,以及黄瓜腋负载果实与否的内的因素 相似文献
7.
8.
贵州山茶属五种野生植物的光合特性研究 总被引:10,自引:2,他引:8
研究了小黄花茶(CamellialuteofloraY.K.Li)、美丽红山茶(C.delicataY.K.Li),威宁短柱油茶(C.salenensisStapfexBeau.)、狭叶瘤果茶(C.neriifoliaChang)和四球茶(C.tachangensisF.S.Zhanlg)贵州山茶属五种野生植物的光合生理,均为C3植物,其CO2补偿点在60μL/L左右,光呼吸速率与总光合的比值为25%左右,光补偿点800~2500lx,光饱和点1600~41000lx。其中小黄花茶的光补偿点及光饱和点最低,威宁短柱油茶的光补偿点及光饱和点最高;净光合速率(Pn)6.00~15.00CO2mg/(dm2·h),光呼吸速率(Pr)2.00~5.00CO2mg/(dm2·h),其中威宁短柱油茶的Pn及Pr均较高,四球茶的Pn及Pr均较低;Dr(暗呼吸速率)0.70~2.60CO2mg/(dm2·h),其中威宁短柱油茶的Dr较高,小黄花茶的Dr较低。Pn、Pr及Dr相互间呈正相关;Chl.(a+b)(叶绿素)含量7.60~12.50mg/dm2,其中小黄花茶的含量较高,威宁短柱油茶的含量较低。 相似文献
9.
大白菜对CO_2浓度倍增的生理生态反应 总被引:11,自引:0,他引:11
利用半封闭式同化箱研究在700、500、350μL/LCO2浓度条件下大白菜莲座期生长性状和生理特性的不同反应。结果表明,提高CO2浓度,可促进白菜光合作用,延长光合时间,降低光补偿点。与350μL/L相比,700和500μL/L光合速率增加68%和39%,光合时间延长55和25分钟。同时,CO2浓度增高,减小了气孔导度,叶温升高,蒸腾系数减弱,从而提高了水分利用率。700和500比350μL/L叶温分别增加0.5℃和0.13℃,蒸腾系数降低27.1%和23.1%,叶面积增长86.4%和79.1%,叶片数增加80.7%和40.9%.鲜重增加76.1%和52.9%,干重增加31.0%和28.2%。 相似文献
10.
无病毒草莓丰香(Fragaria ananassa Duch.cv.Fengxiang)离体试管苗具有光合能力,但其光合作用受培养基中的蔗糖浓度、培养光强及培养容器内CO2浓度的影响。在无蔗糖或含有较低浓度蔗糖的培养基上和较高的培养光强下生长的试管苗,其净光合速率(Pn)、光饱和点和表观量子效率(AQY)较高,光补偿点较低。生长有小苗的培养容器内的CO2浓度只有70-120μl·l-1,远远低于大气的CO2浓度。随着向培养容器中通入CO2浓度的增加,试管苗的Pn增加。培养6周试管苗的Pn高于培养3周的试管苗,培养容器内的CO2浓度6周培养的低于3周。 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.
HU Zhi-cheng ZHU Jia-yuan ZHU Bin GUO Dong CHEN Bin ZHANG Kai HU Kun-hua LI Ming-tao TANG Bing 《园艺学报》2011,27(9):1802-1806
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.
《International Journal of Fruit Science》2013,13(3):101-120
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.
Duncan Brean W. Boyle Shannon Breininger David R. Schmalzer Paul A. 《Landscape Ecology》1999,14(3):291-309
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