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六种杜鹃花属植物花粉活力测定方法的比较研究 总被引:1,自引:0,他引:1
选取睫毛杜鹃(Rhododendron ciliatum)、多鳞杜鹃(Rhododendron polylepis)、薄皮杜鹃(Rhdodenron taronense)、映山红(Rhododendron simsii)、马银花(Rhododendron ovatum)和比利时杜鹃(Rhododendron hybridum)为研究对象,通过蔗糖、H3BO3、CaCl2单因子及L25( 53)正交试验对它们进行花粉萌发试验研究,比较I2-Kl染色法、TTC染色法、联苯胺染色法、MTT染色法4种花粉活力测定方法的不同.结果表明:蔗糖、H3BO3、CaCl2及3因子交互效应对杜鹃花花粉萌发有显著影响.适宜的离体培养基配方依杜鹃花种类不同而不同,睫毛杜鹃为:蔗糖150 g/L +H3BO3 0 mg/L +CaCl2 50 mg/L;映山红为:蔗糖100 g/L +H3BO3 100 mg/L +CaCl20 mg/L;马银花为:蔗糖50 g/L+ H3BO3 200 mg/L +CaCl2 0 mg/L;比利时杜鹃为:蔗糖150 g/L+ H3BO3100 mg/L +CaCl2 0 mg/L.MTT染色法是简单快速测定杜鹃花花粉活力的最适染色法. 相似文献
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对杜鹃红山茶(Camellia azalea)苗期生长大量营养元素进行诊断,为指导杜鹃红山茶苗木科学施肥和高效培育提供依据。以杜鹃红山茶0.5 年生嫁接苗为材料,用 N、P、K 三元二次正交旋转组合设计进行施肥试验,以处理12个月后嫁接苗N、P、K元素含量为依据,采用P/N、K/N、P/K作为诊断指标,计算相应系数并用诊断施肥综合法(DRIS)和指数法对N、P、K需求关系进行分析。杜鹃红山茶P和N元素含量最佳比值为0.074±0.108;K和N元素含量最佳比值为0.509±0.500;P和K元素含量最佳比值为0.148±0.090,建立杜鹃红山茶DRIS营养诊断指数表。杜鹃红山茶对N肥和K肥的反应比P肥更为敏感,栽培管理中应多施用N肥和K肥,促进苗木生长。 相似文献
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植物通过提高光能利用能力和光保护途径以响应环境光强的增加, 但不同植物对环境光强增加的生理响应存在差异, 从而导致植物对光环境的适应性不一致。为探讨植物对光环境变化的生理响应及其适应机制, 该文以遮阴条件下培养1年的2种杜鹃属(Rhododendron)植物比利时杜鹃(R. hybrida)和杜鹃(R. simsii)为材料, 对其由遮阴后转入全光照下培养5天时的叶片叶绿素荧光参数及其快速光曲线变化进行了比较研究, 以期从叶片吸收光能分配和光保护机制的角度探讨这2种植物对光环境变化的适应机制。结果表明: 全光照降低了喜阴植物比利时杜鹃叶片的光化学反应和热耗散能力, 且其吸收光能分配于光化学反应和调节性能量耗散部分的比例减少, 导致光系统II反应中心过量激发能积累, 造成了叶片光抑制甚至光破坏。杜鹃作为耐阴喜光植物对光环境变化具有较强的适应性, 具有较高的光化学反应、热耗散和环式电子传递能力等内在生理特性; 在遮阴和全光照两种光环境下均能维持较高的吸收光能在光化学反应和调节性能量耗散部分的分配比例, 从而保护了光合机构的正常运行, 是其全光照强光未造成叶片光抑制的原因。 相似文献
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为探索不同水平N和P对等鞭金藻(Isochrysis galbana Parke)产量及油脂品质的影响,在富N(80.00 mg·L-1 NO3--N)和无N(0.00 mg·L-1 NO3--N)条件下设置富P、限P和无P(20.00、0.25和0.00 mg·L-1 PO43--P)共6组培养基,对培养10 d时等鞭金藻的藻体质量浓度、P吸收量、总脂肪酸质量分数和脂肪酸产率变化、13个脂肪酸组分及其质量分数以及EPA和DHA的相对含量和产量进行了比较分析。结果显示:在富N培养基中,等鞭金藻藻体质量浓度的增幅明显高于无N培养基且按培养基中P质量浓度从高到低依次降低。总体上看,随培养时间延长,等鞭金藻的总脂肪酸质量分数持续升高,且在富N培养基中总脂肪酸质量分数高于无N培养基;其中,富N限P和富N无P培养基中的总脂肪酸质量分数基本上均高于富N富P培养基。富N培养基中各脂肪酸组分的质量分数大体上高于无N培养基,且限P培养基中各脂肪酸组分的质量分数大体上高于富P和无P培养基。在富N富P培养基中1 L藻体的P吸收量最高(0.0148 mg),并且吸收的P绝大部分被贮存在藻体中,而在无N富P培养基中P吸收量明显降低(0.0098 mg)。在富N富P培养基中,饱和脂肪酸质量分数和相对含量及EPA相对含量和产量均最低,但DHA相对含量和产量则最高。在富N限P培养基中,等鞭金藻的EPA产量和脂肪酸产率均最高,其DHA产量也较高;5种优质脂肪酸组分(即C18:1n9c、C16:0、C14:0、C18:0和C16:1n9)的总相对含量达到65.86%,尤其是C18:1n9c,其相对含量高达28.19%。综合分析结果显示:富N培养基有利于等鞭金藻的生长、P吸收及脂肪酸积累,其中,富N限P培养基是等鞭金藻高产且产优质油脂的适宜培养基。此外,等鞭金藻不但是生产生物柴油的优质资源而且是生产DHA和清除废水中P的潜在生物资源。 相似文献
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濒危黄杜鹃的离体快速繁殖体系研究 总被引:2,自引:0,他引:2
以濒危野生黄杜鹃(Rhododendron molle G.Don)茎尖为试材,比较研究3种不同基本培养基和9个激素浓度组合对不定芽增殖的影响,以建立黄杜鹃的快速繁殖体系.结果表明:3种不同基本培养基对野生黄杜鹃不定芽增殖的效果差异显著;相同激素种类与浓度下,WPM培养基上的不定芽增殖系数最大,达10.5.激素种类与浓度对黄杜鹃不定芽的增殖影响差异很大,以单独使用1.0 mg/L ZT最佳,再生率达100%,不定芽增殖系数为10.5.综合分析显示,黄杜鹃不定芽增殖的最佳培养条件为WPM+ZT 1.00 mg/L;健壮、整齐一致的不定芽在1/2 WPM+0.05 mg/L NAA上生根,40 d后生根率可达86.7%,驯化成活率达92.86%. 相似文献
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硝态氮(NO3^—)对水稻侧根生长及其氮吸收的影响 总被引:6,自引:0,他引:6
侧根是植物吸收利用土壤养分的重要器官 ,其生长发育受内部遗传因子和外部环境矿质养分的影响。通过琼脂分层培养发现 :局部供应NO-3 可以诱导水稻 (OryzasativaL .)主根或不定根上侧根的生长。为研究旱种条件下NO-3 对水稻侧根发育及其N吸收的影响 ,设置了 3个蛭石培养实验 :分根处理、全株缺N、全株供N处理。分根处理 (一半根系供应 3mmol/LKNO3,另一半根系供应 3mmol/LKCl)结果表明 :局部供应NO-3 能够促进水稻侧根生长。而在全株处理下 ,N饥饿诱导了侧根的伸长。水稻根系对NO-3 的这两种反应都存在着显著的基因型差异。同时对地上部N浓度、可溶性总糖含量及N含量分析表明 ,这些生理指标在分根处理与全株加N处理中的差异均不显著 ,表明分根处理也能基本满足植株正常生长对N的需求。在分根处理中 ,水稻的N含量与分根处理中供N一侧的平均侧根长度存在显著正相关 ,这表明在养分不均一的介质中 ,侧根长度对水稻N素吸收具有十分重要的作用。而在N素充足的条件下 ,两者之间的相关性并不显著 ,这暗示在养分充足的环境下 ,侧根长度可能并不是决定根系吸收N素的主要因素 相似文献
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The effect of nitrate, nitrite, nitric oxide (NO), and nitrous oxide on a mixed, mesophilic (35 degrees C) methanogenic culture was investigated. Short-term inhibition assays were conducted at a concentration range of 10-350 mg N/L nitrate, 17-500 mg N/L nitrite, 0.02-0.8 mg N/L aqueous NO, and 19-191 mg N/L aqueous nitrous oxide. Simultaneous methane production and N-oxide reduction was observed in 10 and 30 mg N/L nitrate and 0.02 mg N/L aqueous NO-amended cultures. However, addition of N-oxide resulted in immediate cessation of methanogenesis in all other cultures. Methanogenesis completely recovered subsequent to the complete reduction of N-oxides to nitrogen gas in all N-oxide-amended cultures, with the exception of the 500 mg N/L nitrite- and 0.8 mg N/L aqueous NO-amended cultures. Partial recovery of methanogenesis was observed in the 500 mg N/L nitrite-amended culture in contrast to complete inhibition of methanogenesis in the 0.8 mg N/L aqueous NO-amended culture. Accumulation of volatile fatty acids was observed in both cultures at the end of the incubation period. Among all N-oxides, NO exerted the most and nitrate exerted the least inhibitory effect on the fermentative/methanogenic consortia. The effect of multiple additions of nitrate (300 mg N/L) on the same methanogenic culture was also investigated. Long-term exposure of the methanogenic culture to nitrate resulted in an increase of N-oxide reduction rates and decrease of methane production rates, which was attributed to changes in the microbial community structure due to nitrate addition. 相似文献
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R. Van Den Driessche 《Plant and Soil》1971,34(1):421-439
Summary Differences in growth responses of Douglas fir, western hemlock, Sitka spruce, and white spruce to nitrate and ammonium N
sources were examined in sand culture and artificial soil culture. Effects of the two forms of N on growth, needle area, and
N uptake of three Douglas fir halb-sib progenies were examined in a second sand culture. Response of Douglas fir to the two
forms of N was followed over two years in nursery soil of different pH levels.
In sand culture 1 mean seedling dry weight of all species, except hemlock, was greatest when ammonium N and nitrate N were
provided in equal amounts. In all species, except Sitka spruce, ammonium alone resulted in greater growth than nitrate alone.
Use of ammonium N resulted in greater growth of all species, than was obtained with nitrate N, at pH values in the region
5.4 and 7.5 in artificial soil culture. Only Douglas fir showed substantial differences due to N source below pH 5. Growth
of all species was greater at pH 5.4 than at 7.5 in each N source treatment.
Growth of Douglas fir seedlings was greatest with ammonium N and least with nitrate N in sand culture 2. Supply of nitrate
and ammonium in equal proportions resulted in intermediate growth. Leaf area/plant weight ratio was unaffected by N source.
Analysis of nutrient solutions showed appreciable nitrification of ammonium N during the 7 days between solution changes.
In the three greenhouse experiments, with little exception, increase in proportion of ammonium in N supply resulted in increase
of seedling tissue N concentration. This effect was more pronounced in roots than shoots. Total N uptake by ammonium fed seedlings
was about double the N uptake of nitrate fed seedlings in sand culture 2.
Nursery grown Douglas fir seedlings showed greater growth response to ammonium sulphate than to calcium nitrate, and this
appeared due entirely to form of N supply in the first year. A similar response in the second year was partly due to greater
soil acidification by ammonium sulphate. Compared with calcium nitrate, ammonium sulphate increased N concentration of one-year
old shoots, but this difference was not detected by foliar analysis of two-year old seedlings. 相似文献
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侧根是植物吸收利用土壤养分的重要器官,其生长发育受内部遗传因子和外部环境矿质养分的影响.通过琼脂分层培养发现:局部供应NO-3可以诱导水稻( Oryza sativa L.)主根或不定根上侧根的生长.为研究旱种条件下NO-3对水稻侧根发育及其N吸收的影响,设置了3个蛭石培养实验:分根处理、全株缺N、全株供N处理.分根处理(一半根系供应3 mmol/L KNO3,另一半根系供应3 mmol/L KCl)结果表明:局部供应NO-3 能够促进水稻侧根生长.而在全株处理下,N饥饿诱导了侧根的伸长.水稻根系对NO-3的这两种反应都存在着显著的基因型差异.同时对地上部N浓度、可溶性总糖含量及N含量分析表明,这些生理指标在分根处理与全株加N处理中的差异均不显著,表明分根处理也能基本满足植株正常生长对N的需求.在分根处理中,水稻的N含量与分根处理中供N一侧的平均侧根长度存在显著正相关,这表明在养分不均一的介质中,侧根长度对水稻N素吸收具有十分重要的作用.而在N素充足的条件下,两者之间的相关性并不显著,这暗示在养分充足的环境下,侧根长度可能并不是决定根系吸收N素的主要因素. 相似文献
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Thioalkalivibrio denitrificans is the first example of an alkaliphilic, obligately autotrophic, sulfur-oxidizing bacterium able to grow anaerobically by denitrification. It was isolated from a Kenyan soda lake with thiosulfate as electron donor and N2O as electron acceptor at pH 10. The bacterium can use nitrite and N2O, but not nitrate, as electron acceptors during anaerobic growth on reduced sulfur compounds. Nitrate is only utilized as nitrogen source. In batch culture at pH 10, rapid growth was observed on N2O as electron acceptor and thiosulfate as electron donor. Growth on nitrite was only possible after prolonged adaptation of the culture to increasing nitrite concentrations. In aerobic thiosulfate-limited chemostats, Thioalkalivibrio denitrificans strain ALJD was able to grow between pH values of 7.5 and 10.5 with an optimum at pH 9.0. Growth of the organism in continuous culture on N2O was more stable and faster than in aerobic cultures. The pH limit for growth on N2O was 10.6. In nitrite-limited chemostat culture, growth was possible on thiosulfate at pH 10. Despite the observed inhibition of N2O reduction by sulfide, the bacterium was able to grow in sulfide-limited continuous culture with N2O as electron acceptor at pH 10. The highest anaerobic growth rate with N2O in continuous culture at pH 10 was observed with polysulfide (S8(2-)) as electron donor. Polysulfide was also the best substrate for oxygen-respiring cells. Washed cells at pH 10 oxidized polysulfide to sulfate via elemental sulfur in the presence of N2O or O2. In the absence of the electron acceptors, elemental sulfur was slowly reduced which resulted in regeneration of polysulfide. Cells of strain ALJD grown under anoxic conditions contained a soluble cd1-like cytochrome and a cytochrome-aa3-like component in the membranes. 相似文献
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为拯救出一株能够在动物传代细胞中高水平复制的H3N2亚型猪流感疫苗株,利用反向遗传操作技术,将A/Goose/Dalian/3/01(H9N2)毒株的PB1、PA、NP、M、NS基因和A/PR/8/34毒株的PB2基因作为内部基因与猪流感病毒A/Swine/Henan/S4/01(H3N2)毒株的HA、NA基因进行重组,成功拯救出了具有高度细胞适应性毒株rH3N2株,该毒株接毒MDCK细胞60h后,血凝价可以达到1∶512,表明该毒株具有高度适应细胞繁殖特性,为H3N2亚型猪流感病毒细胞培养型疫苗的研制奠定了基础。 相似文献
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交叉培养法研究养分对作物幼苗释放N2O的影响 总被引:8,自引:0,他引:8
为验证土壤中N2 O能否通过植物的输导组织由叶片释放从而干扰植物直接释放N2 O的定量测定 ,实验采用分室隔离法确证了土壤N2 O对测定某些作物 (如玉米、高粱 )直接释放N2 O的干扰 ;采用交叉培养法消除了这种干扰 ,准确地测定了大豆、玉米幼苗直接释放N2 O的强度 ;并研究了N、P营养与植物释放N2 O及体内NO 3 N浓度之间的相关性 . 相似文献
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Nitrogen Fixation by Rhodospirillum rubrum Grown in Nitrogen-limited Continuous Culture 总被引:11,自引:6,他引:5
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Cell-free extracts of the photosynthetic bacterium Rhodospirillum rubrum were inconsistent in reducing N(2). An internally illuminated fermentor, designed for the continuous culture of this organism on N(2) under nitrogen-limited conditions, produced cells which yielded cell extracts with consistent activity for cell-free N(2) fixation. A nitrogen-limited continuous culture, supplied ammonia rather than N(2), gave cell-free extracts with even more active N(2) fixation. Extracts of cells grown in the fermentor with glutamate nitrogen as the limiting nutrient in continuous culture did not reduce N(2), but whole cells fixed (15)N-enriched N(2). The discovery that cells from ammonia and glutamate nitrogen-limited continuous cultures are capable of N(2) reduction suggests that R. rubrum cells produce the N(2)-reducing enzymes in response to conditions of nitrogen deficiency rather than in response to the presence of N(2). Examination of the effect of the pN(2) on N(2) reduction by cell-free preparations of R. rubrum indicated that the K(N(2)) is approximately 0.071 atm. Cell-free extracts from R. rubrum were tested for their ability to reduce substrates other than N(2). 相似文献
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Growth characteristics of the cyanobacterium Nostoc flagelliforme in photoautotrophic, mixotrophic and heterotrophic cultivation 总被引:1,自引:0,他引:1
Nostoc flagelliforme is a terrestrial cyanobacterium with high economic value. Dissociated cells separated from a natural colony of N. flagelliforme were cultivated for 7 days under either phototrophic, mixotrophic or heterotrophic culture conditions. The highest biomass,
1.67 g L−1 cell concentration, was obtained under mixotrophic culture, representing 4.98 and 2.28 times the biomass obtained in phototrophic
and heterotrophic cultures, respectively. The biomass in mixotrophic culture was not the sum as that in photoautotrophic and
heterotrophic cultures. During the first 4 days of culture, the cell concentration in mixotrophic culture was lower than the
sum of those in photoautotrophic and heterotrophic cultures. However, from the 5th day, the cell concentration in mixotrophic
culture surpassed the sum of those obtained from the other two trophic modes. Although the inhibitor of photosynthetic electron
transport DCMU [3-(3,4-dichlorophenyl)-1,1-dimethylurea] efficiently inhibited autotrophic growth of N. flagelliforme cells, under mixotrophic culture they could grow by using glucose. The addition of glucose changed the response of N.flagelliforme cells to light. The maximal photosynthetic rate, dark respiration rate and light compensation point in mixotrophic culture
were higher than those in photoautotrophic cultures. These results suggest that photoautotrophic (photosynthesis) and heterotrophic
(oxidative metabolism of glucose) growth interact in mixotrophic growth of N. flagelliforme cells. 相似文献
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Nitrous oxide production by Alcaligenes faecalis under transient and dynamic aerobic and anaerobic conditions. 总被引:8,自引:0,他引:8
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Nitrous oxide can be a harmful by-product in nitrogen removal from wastewater. Since wastewater treatment systems operate under different aeration regimens, the influence of different oxygen concentrations and oxygen fluctuations on denitrification was studied. Continuous cultures of Alcaligenes faecalis TUD produced N2O under anaerobic as well as aerobic conditions. Below a dissolved oxygen concentration of 5% air saturation, the relatively highest N2O production was observed. Under these conditions, significant activities of nitrite reductase could be measured. After transition from aerobic to anaerobic conditions, there was insufficient nitrite reductase present to sustain growth and the culture began to wash out. After 20 h, nitrite reductase became detectable and the culture started to recover. Nitrous oxide reductase became measurable only after 27 h, suggesting sequential induction of the denitrification reductases, causing the transient accumulation of N2O. After transition from anaerobic conditions to aerobic conditions, nitrite reduction continued (at a lower rate) for several hours. N2O reduction appeared to stop immediately after the switch, indicating inhibition of nitrous oxide reductase, resulting in high N2O emissions (maximum, 1.4 mmol liter-1 h-1). The nitrite reductase was not inactivated by oxygen, but its synthesis was repressed. A half-life of 16 to 22 h for nitrite reductase under these conditions was calculated. In a dynamic aerobic-anaerobic culture of A. faecalis, a semisteady state in which most of the N2O production took place after the transition from anaerobic to aerobic conditions was obtained. The nitrite consumption rate in this culture was equal to that in an anaerobic culture (0.95 and 0.92 mmol liter-1 h-1, respectively), but the production of N2O was higher in the dynamic culture (28 and 26% of nitrite consumption, respectively). 相似文献