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1.
NaCl胁迫下中国南瓜杂交种和黑籽南瓜植株离子吸收与积累特性研究 总被引：1，自引：0，他引：1
营养液栽培条件下,在成株期以 80 mmol/L NaCl 胁迫中国南瓜 360-3×112-2 F1和黑籽南瓜植株,10d 后,测定了植株的生长量和不同器官中Na+、K+、Ca2+、Mg2+的含量。结果表明,NaCl 胁迫下两种材料的生长受到明显抑制,360-3×112-2杂交种的生长抑制比黑籽南瓜植株较轻。NaCl 胁迫后两种南瓜植株体内Na+含量升高,360-3×112-2杂交种的Na+主要累积在根部,黑籽南瓜主要积累在茎中;K+、Ca2+、Mg2+的含量在植株体内呈下降的趋势,但360-3×112-2杂交种的上位叶中的含量却上升。NaCl胁迫下,因Na+的积累抑制了K+的吸收,植株各器官的K+/Na+普遍降低,但黑籽南瓜比360-3×112-2杂交种的K+/Na+下降明显。这些结果说明,两种南瓜受到盐胁迫后Na+的主要积累器官不同,致使地上部各器官有不同的K+、Ca2+、Mg2+吸收和积累特性,K+/Na+降低幅度也不同,从而影响了植株的生长,产生了耐盐性的差异。360-3×112-2杂交种耐盐性比黑籽南瓜强,可望作为耐盐砧木在瓜类生产上使用。 相似文献
2.
为了筛选黄瓜的耐盐砧木,采用营养液栽培,分别以前期试验筛选的耐盐性较强的中国南瓜360-3×112-2杂交种和黑籽南瓜为砧木,以黄瓜品种津春2号为接穗,研究了成株期不同砧木嫁接黄瓜在80mmol.L-1 NaCl胁迫和没有NaCl胁迫下的产量与品质指标。结果表明:没有NaCl胁迫时,以360-3×112-2杂交种为砧木的嫁接黄瓜在产量指标上与以黑籽南瓜为砧木的嫁接黄瓜相当,在果实感官品质和营养品质上则优于以黑籽南瓜为砧木的嫁接黄瓜果实。NaCl胁迫时对嫁接黄瓜的产量和果实品质影响较大,单果重和单株产量降低,果实畸形率升高,风味变差,果实维生素C、游离氨基酸、可溶性糖和果实含水量减少,而纤维素和可滴定酸含量升高,以360-3×112-2杂交种为砧木的嫁接黄瓜受NaCl胁迫影响较以黑籽南瓜为砧木的嫁接黄瓜要小。因此,中国南瓜"360-3×112-2"杂交种具备黄瓜耐盐砧木品种的优良特性,可作为砧木品种在生产上应用。 相似文献
3.
通过水培试验,研究了不同浓度的铅胁迫对杨梅（Myrica rubra Sieb. et Zucc.）叶片的叶绿素含量、可溶性蛋白质含量、可溶性糖含量、超氧化物歧化酶（SOD）活性、过氧化物酶（POD）活性、丙二醛（MDA）含量以及根系活力的影响。结果表明,在2 mmol·L^-1低铅条件下,杨梅叶片叶绿素含量和可溶性蛋白质含量在30 d内与对照相比无显著性差异;叶片可溶性糖和MDA含量在2 mmol·L^-1低铅处理第10 d即比对照显著增加;根系活力在2 mmol·L^-1低铅胁迫处理20 d后比对照显著降低;叶片SOD和POD活性在2 mmol·L^-1低铅胁迫下活性随着处理时间的延长而呈先升后降的变化趋势,在低铅处理第20 d SOD 和POD活性达到最大。在6 mmol·L^-1高铅胁迫下,杨梅叶片的叶绿素含量、可溶性蛋白质含量、SOD活性、POD活性、MDA含量以及根系活力均随着处理时间的延长而不断降低;而叶片可溶性糖含量在高铅处理30 d时比对照有所增加。综上所述,杨梅在低铅条件下可诱导活性氧清除系统以及叶片可溶性糖含量增加以减少由于铅胁迫带来的活性氧代谢失衡和缺水对植株的伤害。 相似文献
4.
采用营养液栽培,研究了以中国南瓜“360-3×112-2”杂交种和黑籽南瓜为砧木,以“津春2号”为接穗的2种嫁接黄瓜和“津春2号”自根黄瓜成株期在 80 mmol/L NaCl 胁迫12 d 后的生长状况和光合能力,以及试验期间叶片氮素代谢及其关键酶活性的动态变化。结果表明,NaCl 胁迫12 d 后以中国南瓜“360-3×112-2”杂交种为砧木嫁接黄瓜植株的主蔓生长速率、第一片功能叶面积、全株鲜重和光合参数均高于自根黄瓜和以黑籽南瓜为砧木的嫁接黄瓜; 且以“360-3×112-2”杂交种为砧木嫁接黄瓜的生长状况好于以黑籽南瓜为砧木的嫁接黄瓜。NaCl 胁迫处理植株叶片中硝态氮、铵态氮含量、谷氨酰胺合成酶(Gs)活性和可溶性蛋白含量比对照先高后低; 而硝酸还原酶(NR)活性先低后回升,但仍低于对照,说明NaCl 胁迫下,黄瓜叶片氮素代谢能力的降低。不同处理氮素代谢能力的差异其原因在于根系吸收氮源的能力差异。NaCl 胁迫对以“360-3×112-2”杂交种为砧木的黄瓜植株生长抑制较小,氮素代谢能力下降较少,表现出较强的耐盐性,可以作为一个黄瓜耐盐砧木在生产上使用。 相似文献
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《植物营养与肥料学报》2010,(5)
采用营养液栽培,研究了以中国南瓜"360-3×112-2"杂交种和黑籽南瓜为砧木,以"津春2号"为接穗的2种嫁接黄瓜和"津春2号"自根黄瓜成株期在80 mmol/L NaCl胁迫12 d后的生长状况和光合能力,以及试验期间叶片氮素代谢及其关键酶活性的动态变化。结果表明,NaCl胁迫12 d后以中国南瓜"360-3×112-2"杂交种为砧木嫁接黄瓜植株的主蔓生长速率、第一片功能叶面积、全株鲜重和光合参数均高于自根黄瓜和以黑籽南瓜为砧木的嫁接黄瓜;且以"360-3×112-2"杂交种为砧木嫁接黄瓜的生长状况好于以黑籽南瓜为砧木的嫁接黄瓜。NaCl胁迫处理植株叶片中硝态氮、铵态氮含量、谷氨酰胺合成酶(Gs)活性和可溶性蛋白含量比对照先高后低;而硝酸还原酶(NR)活性先低后回升,但仍低于对照,说明NaCl胁迫下,黄瓜叶片氮素代谢能力的降低。不同处理氮素代谢能力的差异其原因在于根系吸收氮源的能力差异。NaCl胁迫对以"360-3×112-2"杂交种为砧木的黄瓜植株生长抑制较小,氮素代谢能力下降较少,表现出较强的耐盐性,可以作为一个黄瓜耐盐砧木在生产上使用。 相似文献
6.
南瓜发芽期对Na2CO3胁迫的生理响应及耐受性评价 总被引：3，自引：2，他引：1
研究了南瓜发芽期对Na2CO3胁迫的生理响应及耐受性评价。结果显示,在不同Na2CO3胁迫下,南瓜的发芽率、幼苗鲜重、主根长、侧根数和下胚轴长与对照相比均有显著差异,但下胚轴粗度变化不显著。随Na2CO3胁迫程度的加大,3个南瓜品种的相对电导率、可溶性糖含量和SOD活性呈上升趋势,丙二醛含量和根系活力则呈先升后降趋势。对11个指标进行的主成分分析显示,下胚轴长、侧根数、下胚轴粗度、发芽率、丙二醛含量和可溶性糖含量,6项指标在评价南瓜Na2CO3耐性方面比较重要。 相似文献
7.
[目的]γ-氨基丁酸(GABA)可增强作物品质和抗逆性,但其效果是否受植株根系耐盐性的影响尚不明确。因此,研究添加外源GABA对不同耐盐性番茄嫁接苗的生理调节机制及生长的影响,为小分子氨基酸在蔬菜生产中的应用提供理论依据。[方法]以耐盐性较强的砧用番茄‘OZ-006’为砧木、对盐分较敏感的‘中杂9号’为接穗形成的嫁接苗(RS)为材料,以‘中杂9号’自嫁接苗(SS)为对照材料,进行无土营养液栽培试验。以Hoagland营养液为基础,以调节NaCl浓度至175 mmol/L形成的盐胁迫条件作为对照(CK),在CK基础上设置添加5 mmol/L GABA处理(+G)。从处理后3天起,测定了幼苗生长、Na+积累、氨基酸含量及活性氧代谢指标。[结果]随着NaCl胁迫时间的延长,SS和RS幼苗均显著受到盐胁迫伤害,但RS幼苗盐害指数及Na+含量显著低于SS幼苗,其生长速率、叶绿素含量及氨基酸含量显著高于SS幼苗,其O2·-和MDA含量显著低于SS幼苗,表现为耐盐性显著高于SS幼苗。添加外源GABA后,SS和RS幼苗的鲜重、生长速率、叶绿素及氨基酸(GABA、谷氨酸和脯氨酸)含量、抗氧化酶(SOD、POD和CAT)活性均显著提高,根系和叶片内Na+含量、O2·-产生速率及MDA含量均显著降低,且SS幼苗耐盐性提高的效果大于RS幼苗。[结论]盐胁迫显著影响番茄幼苗的生长,尤其对耐盐性弱的品种生长抑制更加显著。γ-氨基丁酸(GABA)可有效提高番茄嫁接苗的耐盐性,主要原因在于GABA为幼苗提供了氮素营养,促进了盐胁迫下植物的生长和叶绿素的合成,同时GABA诱导细胞内多种氨基酸含量上升,叶片渗透调节能力增强,从而抑制了Na+过量积累,缓解了细胞内活性氧积累带来的膜伤害。此外,GABA添加对耐盐性弱的番茄嫁接苗耐盐性的提升效果比对耐盐性强的番茄嫁接苗更加明显。因此,在盐胁迫条件下,施用外源小分子氨基酸(如GABA)可能是提高作物耐盐能力的有效措施。 相似文献
8.
2,4-表油菜素内酯对NaCl胁迫下紫花苜蓿幼苗根系生长抑制及氧化损伤的缓解效应 总被引：1，自引：0，他引：1
为探讨外源2,4-表油菜素内酯(2,4-epibrassinolide,EBR)提高紫花苜蓿(Medicago sativa L.)耐盐性的生理调控机制,采用营养液水培法,以紫花苜蓿品种‘中苜3号’和‘陇中苜蓿’为材料,研究Na Cl胁迫下添加外源EBR对紫花苜蓿幼苗根系生长、渗透调节物质含量、抗氧化酶活性、非酶抗氧化物质、活性氧及MDA含量的影响。结果表明:150 mmol·L?1 Na Cl胁迫下,‘中苜3号’、‘陇中苜蓿’幼苗根系的生长显著受到抑制,根系干重和根系活力显著降低,幼苗根系中的可溶性蛋白含量和抗氧化酶活性显著降低,活性氧和MDA含量显著增加,根系脂质过氧化程度加剧,细胞质膜完整性受到破坏。添加0.1μmol·L?1外源EBR显著增加了2个品种苜蓿幼苗的主根长、根系总长度、根系总表面积、根体积、根尖数、根系干重和根系活力,幼苗根系中的可溶性蛋白含量、抗氧化酶(SOD、APX、GPX、CAT、GR)活性、非酶抗氧化物质(As A、GSH)含量均显著增加,超氧阴离子自由基(O2·?)产生速率、羟自由基(OH·)浓度、H2O2含量和膜脂过氧化产物MDA含量显著降低,有效缓解了根系脂质过氧化程度,提高了细胞质膜的完整性。说明外源EBR能够有效缓解Na Cl胁迫对紫花苜蓿幼苗根系生长的抑制作用,增强紫花苜蓿幼苗根系的渗透调节能力和抗氧化系统活性,降低活性氧的积累和膜脂过氧化水平,减小Na Cl胁迫对紫花苜蓿幼苗根系造成的氧化伤害,促进根系生长,增强苜蓿幼苗的抗盐性。 相似文献
9.
温度对盐胁迫小麦抗氧化机制的影响 总被引：3，自引：0，他引：3
本研究以耐盐性不同的8个冬小麦品种为材料,分别在室温(20℃/25℃)和接近小麦生产的低温(10℃/15℃)条件下采用溶液培养,并在苗期进行盐胁迫处理(150 mmol·L-1 Na Cl),研究温度和盐胁迫交互作用对耐盐性不同的小麦抗氧化机制的影响。结果表明,对室温培养的幼苗进行盐胁迫后,耐盐强的小麦幼苗超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)和抗坏血酸过氧化酶(APX)活性均显著升高,并且高于2个耐盐性弱的品种;而耐盐性弱的小麦幼苗盐处理后仅APX活性显著升高,其活性氧(ROS)累积量和叶片相对电导率均高于耐盐小麦;抗旱小麦以上指标介于耐盐品种和耐盐性弱的品种中间。低温培养下进行盐胁迫,谷胱甘肽还原酶(GR)在所有供试品种中均显著升高2~3倍;耐盐品种仅CAT和APX活性升高,抗旱品种SOD、POD和APX以及耐盐性弱的品种SOD和POD活性显著提高。由此得出与室温盐胁迫下小麦抗氧化机制的响应不同,低温盐胁迫条件下,耐盐小麦SOD和POD酶活性受到抑制,主要通过提高抗坏血酸-谷胱甘肽循环的两个关键酶APX和GR活性增加对ROS的清除能力,而抗旱品种和耐盐性弱的品种除GR酶活性显著提高外,SOD和POD对ROS的清除能力均显著增强。在各种抗氧化酶的共同作用下,耐盐性不同的小麦品种之间ROS累积量和叶片电导率等受伤害指标的差异程度与室温盐胁迫相比减弱。 相似文献
10.
《土壤通报》2020,(2):372-380
采用盆栽试验的方法,研究不同NaCl浓度(0、20 m M、50 m M和100 m M)胁迫下,添加复合微生物肥料对番茄幼苗生长、光合色素含量、根系活力和抗氧化指标的影响。结果显示,低盐胁迫(20 m M NaCl)促进了番茄幼苗的生长,但随盐胁迫浓度的升高,生物量逐渐降低,同时降低了根系活力同时下降;不同盐浓度胁迫均提高了番茄叶片内光合色素含量、根系和叶片内抗氧化酶(SOD、POD、CAT)活性、丙二醛(MDA)含量和超氧阴离子自由基(O2.-)产生速率。添加复合微生物肥料显著提高了盐胁迫番茄幼苗生物量、根系活力,、进一步提高了叶片内光合色素含量和根系抗氧化酶活性,显著降低了叶片内抗氧化酶活性;此外,复合微生物肥料的添加使番茄叶片和根系内MAD含量和O2.-产生速率均显著低于盐胁迫处理,使但是提高了叶片和根系内可溶性蛋白含量增加。以上结果表明,复合微生物肥料可通过调节番茄叶片渗透势、提高根系活力和、光合色素含量以及番茄抗氧化损伤的能力来增强番茄幼苗的抗盐性,通过促进光合制造、贮存碳水化合物的能力来,最终提高番茄幼苗生物量的累积。 相似文献
11.
【目的】以富士（Fuji）、 秦冠（Qinguan）嫁接在平邑甜茶（Malus hupehensis Rehd.）上的当年生盆栽苗为试验材料,采用砂培方法,研究了缺氮胁迫和干旱对富士和秦冠生长情况、 光合参数、 植株各部位氮磷钾含量及氮素利用效率的影响,分析比较了低氮干旱条件下富士和秦冠生长及氮素利用的差异,以期为果树生产高效肥水利用提供理论指导。【方法】试验共设四个处理: 正常氮正常水（ZZ）、 低氮正常水（DZ）、 正常氮干旱（ZG）、 低氮干旱（DG）。氮素和水分均设置两个水平,分别为正常氮（6 mmol/L NO-3-N）、 低氮（0.3 mmol/LNO-3-N）、 正常供水（保持盆中砂子相对含水量为饱和含水量的80%~85%）、 干旱处理（保持盆中砂子相对含水量为饱和含水量的60%~65%）。【结果】富士和秦冠的生物量（茎和叶）、 株高茎粗等生长指标以及光合速率、 气孔导度、 蒸腾速率均为正常氮正常水（ZZ）＞低氮正常水（DZ）＞正常氮干旱（ZG）＞低氮干旱（DG）,并且相对应处理下秦冠的以上指标均高于富士;正常供水下,缺氮处理使富士、 秦冠的根冠比比正常氮处理均有所增加,富士提高了2.05%,秦冠提高了22.40%。富士和秦冠的氮、 磷、 钾含量均表现出正常氮正常水（ZZ）＞低氮正常水（DZ）＞正常氮干旱（ZG）＞低氮干旱（DG）; 氮、 钾元素含量在植株各部位的分布顺序依次是叶＞根＞茎,磷元素则是根＞叶＞茎;光合氮素利用效率（PNUE）和氮素利用效率表现为秦冠处理之间差异极显著,富士处理之间差异不显著;秦冠的PNUE和NUE明显高于富士,在低氮正常水（DZ）处理下,秦冠氮肥利用率比富士高42.07%,在低氮干旱（DG）处理下高64.14%;低氮胁迫下富士和秦冠的NUE显著提高,并且秦冠提高的幅度高于富士。【结论】施用氮肥能够显著提高富士与秦冠的干物质量,同等水肥条件下,秦冠生长优于富士;水分亏缺会减少叶片对氮的吸收,干旱条件下适度增施氮肥,可提高果树的抗旱能力;低氮干旱胁迫下秦冠的生长指标、 光合指标及氮素利用效率指标均优于富士,表现出较强的抗低氮干旱胁迫的能力。 相似文献
12.
Kyle Devey Michael Mucalo Gordon Rajendram Joseph Lane 《Communications in Soil Science and Plant Analysis》2015,46(4):72-80
Laser-induced breakdown spectroscopy (LIBS) is a new technique for the analysis of plant material. This study investigates the application of LIBS to pasture-based plant samples. The LIBS measurements were obtained from pelletized pasture samples (100 samples) that had been also analyzed by inductively coupled plasma–optical emission spectroscopy (ICP-OES) following microwave digestion for calibration and comparison purposes. Comparisons for elements sodium (Na), potassium (K), magnesium (Mg), calcium (Ca), manganese (Mn), iron (Fe), copper (Cu), zinc (Zn), boron (B), phosphorus (P), and sulfur (S) showed that LIBS could be used for almost all the standard profile total elements with concentrations down to low mg/kg levels (observed error of Na: 0.024 percent, K: 0.18 percent, Mg: 0.016 percent, Ca: 0.073 percent, P: 0.017 percent, Mn: 31 mg/kg, Fe: 150 mg/kg, Zn: 6.6 mg/kg, and B: 1.1 mg/kg). Elemental analysis at less than mg/kg levels was not possible using LIBS. The elements S and Cu were particularly difficult to analyze with reliability using LIBS at the concentration levels found in the plant samples. Replacing microwave digestion and subsequent ICP analysis with a direct analysis of dried plant samples using LIBS has the potential to improve the productivity and reduce the cost of testing. 相似文献
13.
《中国生态农业学报》2014,(8)
正The Center for Agricultural Resources Research(CARR),the Institute of Genetics and Developmental Biology(IGDB),Chinese Academy of Sciences,invites applicants for several research group leader positions.CARR is one of the research organizations in Chinese Academy of Sciences(CAS).We seek nominations and applications from individuals who have expertise and a record of accomplishment in research areas related to ecology,agro-hydrology, 相似文献
14.
M.A. Callaham Jr. J.M. BlairT.C. Todd D.J. KitchenM.R. Whiles 《Soil biology & biochemistry》2003,35(8):1079-1093
The responses of tallgrass prairie plant communities and ecosystem processes to fire and grazing are well characterized. However, responses of invertebrate consumer groups, and particularly soil-dwelling organisms, to these disturbances are not well known. At Konza Prairie Biological Station, we sampled soil macroinvertebrates in 1994 and 1999 as part of a long-term experiment designed to examine the effects and interactions of annual fire, mowing, and fertilization (N and P) on prairie soil communities and processes. For nearly all taxa, in both years, responses were characterized by significant treatment interactions, but some general patterns were evident. Introduced European earthworms (Aporrectodea spp. and Octolasion spp.) were most abundant in plots where fire was excluded, and the proportion of the total earthworm community consisting of introduced earthworms was greater in unburned, unmowed, and fertilized plots. Nymphs of two Cicada genera were collected (Cicadetta spp. and Tibicen spp.). Cicadetta nymphs were more abundant in burned plots, but mowing reduced their abundance. Tibicen nymphs were collected almost exclusively from unburned plots. Treatment effects on herbivorous beetle larvae (Scarabaeidae, Elateridae, and Curculionidae) were variable, but nutrient additions (N or P) usually resulted in greater densities, whereas mowing usually resulted in lower densities. Our results suggest that departures from historical disturbance regimes (i.e. frequent fire and grazing) may render soils more susceptible to increased numbers of European earthworms, and that interactions between fire, aboveground biomass removal, and vegetation responses affect the structure and composition of invertebrate communities in tallgrass prairie soils. 相似文献
15.
Grete Skrede Berit Karoline Martinsen Anne-Berit Wold Stein-Erik Birkeland Kjersti Aaby 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2013,63(3):193-208
Abstract A 3-year study was carried out to investigate quality parameters in 14 tree fruit and berry species grown in southern Norway. The species were blueberry, apple, aronia, sour cherry, sweet cherry, red raspberry, strawberry, blackcurrant, gooseberry, red currant and elderberry, harvested along with wild bilberry, cloudberry and lingonberry. Significant differences between species were identified for all quality parameters. The coefficient of variation between species was lowest for pH (12.5%), dry matter (18.9%) and soluble solids (25.3%), followed by titratable acids (59.3%), total phenolics (83.8%), antioxidant capacity FRAP (85.7%) and antiradical power by the DPPH-assay (97.8%), total monomeric anthocyanins (132%) and ascorbic acid (137%). Average coefficient of variation within species were lower and ranged from 4 (pH) to 62% (ascorbic acid). Only the FRAP values were significantly affected by harvesting year with lower levels in 2004 than in 2005 and 2006. There were significant interactions between species and harvesting year for dry matter, soluble solids, pH, ascorbic acid and FRAP. The results indicate generic ranges in composition within species independent upon growing location and climate, and the composition of the tree fruits and berries is not likely to deviate from these ranges. It is concluded that desirable composition of tree fruits and berries and their products should primarily be achieved by selection among species rather than searching fors broadened variation within individual species. 相似文献
16.
《Communications in Soil Science and Plant Analysis》2012,43(7):865-877
Potassium (K) fixation and release in soil are important factors in the long-term sustainability of a cropping system. Changes in K concentration and characteristics of K fixation and release in rhizosphere and nonrhizosphere soils in the rapeseed (Brassica napus L.)–rice (Oryza sativa L.) rotation were investigated using a rhizobox system. The concentrations of different forms of K in both rhizosphere and nonrhizosphere soils decreased with plants compared to without plants, regardless of K fertilizer application. Potassium uptake by crops mainly came from the rhizosphere soil. In the treatment without K fertilizer (–K), the main form of K supplied by the soil to the crops was 1.0 mol L?1 nitric acid (HNO3) nonextractable K, followed by nonexchangeable K, and then exchangeable K. In the treatment with K fertilizer (+K), the main K forms supplied by the soil to the crops were exchangeable K and nonexchangeable K. The amount and rate of K fixation after one cycle of the rapeseed–rice rotation was greater in rhizosphere soil than in nonrhizosphere soil. The amount and rate of K fixation of soil in the +K treatment were significantly less than in the –K treatment. The cumulative amounts of K released with 1.0 mol L?1 ammonium acetate (NH4OAc) and 1.0 mol L?1 HNO3 extraction increased with the increasing numbers of extractions, but the K-releasing power of soil by successive extraction decreased gradually and finally became almost constant. The release of K was less in rhizosphere soil than in nonrhizosphere soil. The release of K in the +K treatment was similar to that in the –K treatment in rhizosphere soil, but the K release in nonrhizosphere soil was greater with the +K than the –K treatment. Overall, the information obtained in this study will be helpful in formulating more precise K fertilizer recommendations for certain soils. 相似文献
17.
Y. Bashan J. J. Bustillos L. A. Leyva J.-P. Hernandez M. Bacilio 《Biology and Fertility of Soils》2006,42(4):279-285
Inoculation of wheat seedlings with the plant growth-promoting bacterium Azospirillum brasilense Cd was immobilized in alginate microbeads and, without applying any stress, significantly increased the quantity of several
photosynthetic pigments, such as chlorophyll a, chlorophyll b, and the auxiliary photoprotective pigments violaxanthin, zeaxanthin, antheroxanthin, lutein, neoxanthin, and β-carotene.
This resulted in greener plants with no apparent visible stress. After monitoring the quantity of photosynthetic pigments
for 4 weeks, we observed that inoculated plants had higher quantities of pigments in shoot and stem. The greatest difference
in the quantity of all pigments between inoculated and noninoculated plants occurred in the first week of growth. Regardless
of treatment, the quantity of pigments in stems was three to four times less than the quantity of these pigments in shoots.
Application of Azospirillum, either as liquid inoculant or as alginate microbeads, did not alter the positive effect of the bacteria on pigment production
or the positive response of the plants towards A. brasilense Cd inoculation. 相似文献
18.
Dhritiman Ghosh Velusamy Srinivasan Olli H. Tuovinen Aaron Peacock Mark Radosevich 《Soil biology & biochemistry》2009,41(6):1331-1334
We examined the community composition of microbes that colonized atrazine-containing beads buried in agricultural soils that differed in atrazine treatment history. Bacterial abundance was 5-40-fold greater in atrazine-fortified beads. In beads containing 20 mg atrazine kg−1 buried in soil with a history of atrazine application (conditioned soil), the abundance of Actinobacteria increased approximately 80-fold whereas in control soil, Actinobacteria were enriched only 10-fold and the gamma-Proteobacteria and Planctomycetes increased by 60- and 25-fold, respectively. The gamma-Proteobacteria were enriched by 120- and 230-fold in beads containing 200 mg atrazine kg−1 in conditioned and control soil, respectively. The results demonstrate that BioSep® beads are a suitable matrix for recruiting a diverse subset of the bacterial community involved in atrazine degradation. 相似文献
19.
Pilar García Juan-Vicente Monte Carlos Casanova Consuelo Soler 《Genetic Resources and Crop Evolution》2002,49(1):103-109
Arbitrary oligonucleotides were used as primers to amplifygenomic DNA of 48 wild Spanish populations of Agropyroncristatum, Elymus hispanicus,E. caninus,E. repens,Thinopyrum curvifolium, Th.junceum and Th.intermedium. Genetic diversity was analysedusing nineteen primers. The number of amplified products ranged from8 to 18 per primer and a total of 240 markers were scored. Differentlevels of intraspecific genetic diversity were found, the allogamousspecies E. repens andTh. intermedium being themost variable. Jaccard's similarity coefficients for internalmeasure within and between populations were used to produce a clusterdiagram. The results demonstrate differences in the degree ofsimilarity between taxonomic units. Interpopulational variability andinterspecific genomic relationships of these species arediscussed. 相似文献
20.
The effects of three commonly used fungicides on the colonization and sporulation by a mixture of three arbuscular mycorrhizal (AM) fungi consisting of Glomus etunicatum (Becker & Gerd.), Glomus mosseae (Nicol. & Gerd.) Gerd. & Trappe, and Gigaspora rosea (Nicol. & Schenck) in symbiosis with pea plants and the resulting response of the host-plant were examined. Benomyl, PCNB, and captan were applied as soil drenches at a rate of 20 mg active ingredient kg-1 soil 2 weeks after transplanting pea seedlings in a silty clay-loam soil containing the mixed inocula of AM fungi (AM plants). Effects of fungicides were compared to untreated plants that were inoculated with fungi (AM control). The effect of mycorrhizal inoculation on plant growth was also examined by including nonmycorrhizal, non-fungicide-treated plants (non-AM control). Fungicides or inoculation with AM fungi had only a small effect on the final shoot weights of pea plants, but had greater effects on root length and seed yield. AM control plants had higher seed yields and lower root lengths than the corresponding non-AM plants, and the fungicide-treated AM plants had intermediate yields and root lengths. Seed N and P contents were likewise highest in AM control plants, lowest in non-AM plants, and intermediate in fungicide-treated AM plants. All three fungicides depressed the proportion (%) of root length colonized by AM fungi, but these differences did not translate to reductions in the total root length that was colonized, since roots were longer in the fungicide-treated AM plants. Pea plants apparently compensated for the reduction in AM-fungal metabolism due to fungicides by increasing root growth. Fungicides affected the population of the three fungi as determined by sporulation at the final harvest. Captan significantly reduced the number, relative abundance, and relative volume of G. rosea spores in the final population relative to the controls. The relative volume of G. etunicatum spores was greater in all the fungicide-treated soils, while G. mosseae relative volumes were only greater in the captan-treated soil. These findings show that fungicides can alter the species composition of an AM-fungal community. The results also show that AM fungi can increase seed yield without enhancing the vegetative shoot growth of host plants. 相似文献