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排序方式: 共有96条查询结果,搜索用时 47 毫秒
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光质对组培苗叶绿素含量和碳酸酐酶活性及生长的影响 总被引:2,自引:0,他引:2
以十字花科植物诸葛菜和油菜组培苗为试材,研究4种不同光质对组培苗叶绿素含量、碳酸酐酶活性和生长量的影响,结果表明:红蓝混合光能明显促进组培苗叶片叶绿素含量和碳酸酐酶活性,植株形态建成最佳,但是对生长量没有显著影响;认为红蓝混合光(灯)能提高组培苗的光合自养能力,适合作为组培室光源。 相似文献
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Vincenzo Alterio Emma Langella Giuseppina De Simone Simona Maria Monti 《Marine drugs》2015,13(4):1688-1697
The Carbon Concentration Mechanism (CCM) allows phytoplakton species to accumulate the dissolved inorganic carbon (DIC) necessary for an efficient photosynthesis even under carbon dioxide limitation. In this mechanism of primary importance for diatoms, a key role is played by carbonic anhydrase (CA) enzymes which catalyze the reversible hydration of CO2, thus taking part in the acquisition of inorganic carbon for photosynthesis. A novel CA, named CDCA1, has been recently discovered in the marine diatom Thalassiosira weissflogii. CDCA1 is a cambialistic enzyme since it naturally uses Cd2+ as catalytic metal ion, but if necessary can spontaneously exchange Cd2+ to Zn2+. Here, the biochemical and structural features of CDCA1 enzyme will be presented together with its putative biotechnological applications for the detection of metal ions in seawaters. 相似文献
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盐度对银鲳血清渗透压、过氧化氢酶及鳃离子调节酶活力的影响 总被引:3,自引:2,他引:1
将银鲳幼鱼置于盐度14、25、36的海水中96 h,检测不同盐度下银鲳幼鱼血清渗透压、过氧化氢酶(CAT)以及鳃泡膜质子泵(VHA)、Ca2 -ATP酶、碳酸酐酶(CA)活力随着时间推移而变化的情况。结果显示,血清渗透压变化和盐度呈正相关,并出现波动变化,变化范围为271~379 mOsm/kg,96 h时各盐度组血清渗透压均有恢复正常的趋势。高盐度(36)和低盐度(14)组CAT活力都显著升高而后逐渐恢复(P<0.05),盐度36组8 h时为各值中的最高点。鳃VHA活力变化:盐度14组先上升后回落,对照组基本保持平稳,盐度36组先下降而后恢复。盐度改变后,Ca2 -ATP酶活力都出现显著增强(P<0.05),盐度14组比盐度36组的变化趋势更明显。盐度14和36组CA活力都出现显著增强(P<0.05),其中盐度36组24 h时为最高值。分析实验数据发现,血清渗透压与鳃VHA活力呈极显著负相关,与CA活力在低盐度适应时呈极显著负相关(P<0.01),而盐度14组血清渗透压与Ca2 -ATP酶的变化呈基本相反趋势。结果表明,银鲳幼鱼在适应不同盐度时,血清渗透压会伴随盐度升降而改变,并激活CAT,而鳃VHA、Ca2 -ATP酶、CA在渗透压调节过程中有重要作用。 相似文献
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[目的]比较不同光照条件下不同玉米品种碳酸酐酶(CA)活性的变化情况。[方法]以毕单系列玉米品种(毕单10、13、15、17、18号)为试材,待幼苗长至34叶时在不同光照条件("弱光"、"中光"、"强光")下培养,培养3 d后开始取样测定CA活性,研究不同处理玉米品种CA活性的变化规律。[结果]在"弱光"至"中光"段,随着光照强度的升高,各品种的CA活性逐渐升高,但在"中光"至"强光"段,各品种的CA活性普遍下降,其中毕单15号CA活性降幅最大,毕单18号CA活性降幅最小。"弱光"和"中光"处理各品种的CA活性差别较小,而"强光"处理各品种的CA活性差别较大。[结论]在一定范围内,供试玉米品种的CA活性随光照强度的增加而升高。 相似文献
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Hyacinth bean (Lablab purpureus L.) serves as a good source of vegetable proteins in human diet. Its seeds and pods contain as much as 20–28% protein. Besides, it contains tyrosinase enzyme, which has potential use in the treatment of hypertension. Phosphorus deficiency causes a serious yield and quality constraint of beans at Aligarh, Western Uttar Pradesh, India. To address the problem, a pot experiment was conducted to study the effect of basal phosphorus application on the agricultural performance of this medicinal legume. The plants were grown in pots containing soil supplied with five levels of phosphorus viz. 0, 25, 50, 75 and 100 mg P kg−1 soil as potassium dihydrogen orthophosphate (KH2PO4). The growth and other physiological attributes, leaf nutrient contents, nodule-nitrogen and leghemoglobin content were studied at 60, 90 and 120 days after sowing (DAS), photosynthesis and other related parameters were measured at 90 DAS and yield and quality attributes were recorded at harvest (150 DAS). Nitrate reductase and carbonic anhydrate activities, leaf-N, -P, -K and -Ca contents and nodule-nitrogen and leghemoglobin contents reached the maximum extent at 60 DAS. At 90 and 120 DAS, the values decreased significantly. Chlorophyll content, carotenoids content, and photosynthesis were at maximum level at 90 DAS. At various growth stages, phosphorus application at 75 mg P kg−1 soil resulted in maximum amelioration of most of the parameters studied. It increased the seed-yield by 38.3%, seed-protein content by 14.9% and seed-carbohydrate content by 5.0%, relative to the control. It was concluded that there was a hidden hunger of hyacinth bean for phosphorus owing to soil-phosphorus deficiency that was ameliorated effectively by its basal dressing at 75 mg P kg−1 soil. 相似文献
8.
Vahid Tavallali 《Journal of plant nutrition》2017,40(11):1588-1603
The effects of zinc (Zn) and boron (B) on some physiological and biochemical characteristics of pistachio (Pistacia vera L. cv. Badami) seedlings were evaluated in a greenhouse study. It was found that both high levels (10 and 20 mg B kg?1 soil) and also lack of B account for the reduction in growth and photosynthesis parameters, especially at low Zn levels. Moreover, Zn deficiency resulted in a reduction in the net photosynthetic rate and stomatal conductance. However, the adverse effects of B deficiency and toxicity were alleviated by increasing Zn levels up to 10 mg kg?1 soil. In addition, provided that B and Zn are adequate, synergism can be observed between the two nutrients. This is because sufficient amounts B accelerated the effects of Zn by raising the plant dry weight, photosynthesis parameters, carbonic anhydrase activity, and chlorophyll contents. This increase was reported higher in comparison with Zn alone application. It was concluded that Zn may act as a scavenger of reactive oxygen species (ROS) for mitigating the injury on biomembranes under B stress. Adequate concentration of Zn also prevents uptake and accumulation of excess B in leaf by increasing membrane integrity of root cells. Similarly, B application in adequate concentration plays an important structural role in the cell wall and influences a great variety of physiological processes in pistachio seedlings. 相似文献
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为了探讨盐碱胁迫条件下鱼类渗透生理调节机制,以尼罗罗非鱼(Oreochromis niloticus)为实验材料, PCR扩增得到了Na+/3HCO-共转运子(NBCe1)基因cDNA部分序列,比较了单盐(盐度10、盐度15)、单碱(1.5 g/L、3 g/L NaHCO3)、盐碱混合(盐度10,碱度1.5 g/L;盐度15,碱度3 g/L)胁迫后不同时间(0 h、6 h、12 h、24 h、48 h、72 h、96 h)血清渗透压、离子浓度(Na+、K+、Cl–、Ca2+)以及鳃碳酸酐酶(CA)活性、CA与NBCe1基因mRNA表达变化。结果显示,不同胁迫条件下,血清渗透压、离子浓度、鳃组织 CA 酶活、CA 与 NBCe1基因 mRNA 表达变化均与胁迫强度呈正相关。随时间推移,血清渗透压、离子浓度呈现先上升后下降的变化趋势,单盐、盐碱混合组血清渗透压值较单碱组高。单盐、单碱、盐碱混合组中, NBCe1基因mRNA在鳃中均呈略微上调,但不显著(P>0.05)。单碱组和盐碱混合组鳃CA活性较单盐组高,低盐碱胁迫(盐度10,碱度1.5 g/L)下CA活性较晚达最高值;不同胁迫条件下, CA基因mRNA表达均表现上调,单碱、盐碱混合组更为显著(P<0.05),推测CA较NBCe1对体内3HCO-转运作用更为显著。研究结果为尼罗罗非鱼盐碱适应生理调节提供了基础资料。 相似文献
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