水分胁迫下梨、枣和葡萄叶片中甜菜碱含量的变化

 本研究表明, 在水分供应充足的条件下, 梨、枣和葡萄3 种果树叶片中均含有甜菜碱, 其中枣最高, 梨次之, 葡萄最低; 轻度水分胁迫诱导了梨成龄叶中甜菜碱水平增高将近1 倍; 枣和葡萄叶片中的甜菜碱水平对水分胁迫基本没有响应; 梨在水分胁迫下诱导的甜菜碱主要是由叶片独立合成的。     

外源甜菜碱对高温胁迫下菜豆幼苗的生理效应

以"地豆王"菜豆品种为材料,对2~3叶期幼苗叶面分别喷施0.5、1.0、1.5、2.0mmol/L的甜菜碱溶液,在喷施后将幼苗置于41℃高温下胁迫24 h,研究外源甜菜碱对菜豆幼苗高温胁迫的生理效应。结果表明:喷施适宜浓度的甜菜碱溶液,可以降低菜豆幼苗叶片中的丙二醛含量,提高可溶性蛋白含量与SOD、POD、CAT酶活性,从而缓解高温胁迫对菜豆幼苗的伤害,其中0.5 mmol/L处理效果最明显。     

外源NO缓解果树胁迫的作用机理和研究进展

一氧化氮(NO)是一种重要的信号分子,广泛参与果树的生长发育调控和对生物与非生物环境胁迫的应答反应.外源NO是缓解果树干旱、高温和酸雨等胁迫中重要的信号分子,其信号转导机制目前已广受人们关注.本文综述了NO的来源、NO的双重作用及作用机理、NO与其他信号分子间的关系以及近年来有关外源NO缓解果树胁迫的研究进展.     

外源水杨酸在园艺植物栽培中的应用前景

水杨酸(邻羟基苯甲酸)是一种植物体内产生的简单酚类化合物,广泛存在于高等植物中。现对外源水杨酸(SA)在植物非严重胁迫条件下对植物植株形态、生理生化、光合特性及产量和质量等的影响作用进行了综述;指出了外源水杨酸可提高植物体抗氧化能力,增强光合效率,提高作物产量和品质,以期为水杨酸在园艺植物中的应用提供参考。     

外源甜菜碱对离体烟草叶片保水能力的影响

以离体烟草叶片为材料,研究了外源甜菜碱对其保水能力的影响。结果显示,外源甜菜碱可以有效提高植物的保水能力,减少由于脱水对叶片造成的伤害。     

外源钙对干旱胁迫下复羽叶栾树幼苗水分及光合特性的影响

以1a生复羽叶栾树幼苗为试材,采用称重控水法模拟干旱,研究了外源钙处理对不同干旱胁迫条件下植物幼苗相对含水量、光合特性的影响.结果表明:经外源钙处理,有利于从整体上缓解干旱环境对幼苗的影响,保证植物在逆境中正常生长.对于相对含水量而言,胁迫越严重,下降的幅度越大;经外源钙处理,同一胁迫水平下幼苗相对含水量下降的幅度、速度均减小并且与无钙组同水平处理组均表现出显著性的差异,但并不能使相对含水量恢复到对照水平.植物一般采取低光合、低蒸腾、高水分利用效率的策略来适应干旱环境;通过外源钙处理,光合速率降低的速度及幅度减小,蒸腾作用进一步减小,同时减小了气孔导度的降低,并且提高了干旱条件下的水分利用效率.     

外源NO对重金属胁迫下植物光合作用的缓解效应研究进展

从光合速率、气孔特性、光合色素、叶绿体结构、光合电子传递、光合碳同化等方面,概述外源NO对重金属胁迫下植物光合作用影响的研究进展,以期为外源NO对重金属胁迫下植物光合作用的缓解机制提供理论依据。     

盐胁迫下植物激素水平的研究进展

植物激素在一定程度上能够缓解盐胁迫对植物的伤害。结合盐胁迫对植物生长的影响,从盐胁迫下植物内源激素以及外源激素抵御盐胁迫的机理等方面作了简要分析,为选育抗盐品种提供参考。     

干旱胁迫对苹果叶片中甜菜碱和丙二醛及脯氨酸含量的影响

以盆栽的富士／八棱海棠和新红星／八棱海棠苹果为试材，初步探讨了不同土壤水分状况下甜菜碱含量的变化及其与抗旱性之间的关系。结果表明：在干旱胁迫下，供试品种叶片内的甜菜碱和丙二醛含量均随着胁迫程度的增加呈显著上升趋势，而脯氨酸则是先减少后随着干旱程度的加重含量明显增加。苹果叶片中的甜菜碱含量与丙二醛含量呈正相关，相关系数为0．9130—0．9853，表明甜菜碱含量也是与果树抗旱性密切相关的生理指标。     

外源葡萄糖对番茄盐胁迫耐受性的影响

以番茄为试材,研究了外源葡萄糖(3%、5%、7%)对NaCl胁迫下番茄幼苗的生长、抗氧化酶活性、渗透调节物质的含量变化。结果表明:在NaCl胁迫条件下,一定浓度外源葡萄糖提高了番茄叶片叶绿素含量、超氧化物歧化酶(SOD)、过氧化物酶(POD)的活性,提高了可溶性蛋白质、可溶性糖及脯氨酸含量,降低了叶片丙二醛(MDA)、超氧阴离子自由基(O_2·)和过氧化氢(H_2O_2)的含量,促进了幼苗生长。进一步证实外源葡萄糖对于缓解植物盐害具有重要作用。     

外源甜菜碱对葡萄幼苗抗高温胁迫能力的影响

以1a生酿酒葡萄品种赤霞珠扦插苗为试材,研究了不同浓度的外源甜菜碱(GB)对提高葡萄幼苗抗热性的影响。结果表明,在高温胁迫下,叶面喷施不同浓度的GB均能显著降低葡萄幼苗叶片脯氨酸的含量和丙二醛(MDA)含量,维持较低的膜透性,提高葡萄幼苗叶片可溶性蛋白和抗坏血酸(AsA)含量,从而提高了葡萄幼苗的抗高温胁迫能力。证明GB对减轻高温胁迫引起的伤害,提高葡萄幼苗的抗热能力具有积极的作用。在所设4种GB浓度中以5.0mmol/L处理效果为佳。     

Effect of alleviating products with different mode of action on physiology and yield of olive under drought

Two years old self-rooted Koroneiki olive trees (Olea europaea L.) were subjected to two irrigation regimes, i.e. the fully irrigated and the severely water stressed trees, while they were treated with three alleviating products of different mode of action. The products used were the osmolyte glycine betaine, the antioxidant Ambiol and the heat and irradiance reflecting kaolin clay particles. The effects of product application and water regime on leaf characteristics, shoot and root growth, photosynthesis, leaf compatible solids (carbohydrates) concentration and yield were evaluated. All products applied, exhibited significant alleviating action, based on the relative alleviation index. Irrigated trees exhibited greater growth than drought stressed ones, while the ameliorating products maintained the water content of the leaves under drought conditions and resulted in lower leaf tissue density. On the other hand carbon assimilation rate, stomatal conductance and intrinsic water use efficiency were significantly reduced under drought stress, while the opposite stood for intercellular CO₂. Drought stress resulted in elevated sucrose leaf concentration, while the application of Ambiol increased stachyose concentration and that of glycine betaine did the same with the mannitol concentration. Among the alleviating products tested in this experiment Ambiol and glycine betaine had a significant positive effect on leaf water content, photosynthesis and yield under both drought and well irrigated conditions.     

Glycine betaine counteracts the inhibitory effects of waterlogging on growth,photosynthetic pigments,oxidative defence system,nutrient composition,and fruit quality in tomato

Glycine betaine (GB) is an important organic compound mediating plant responses to environmental stresses. However, despite ample research on this biomolecule, the potential of GB in mitigating the effects of waterlogging in plants has not been established. Therefore, we studied the influence of GB on growth and physiology of tomato plants under waterlogged conditions. Waterlogging reduced plant growth, degraded chlorophyll, and increased concentration of malondialdehyde and hydrogen peroxide that deteriorated membrane integrity. Waterlogging increased catalase and peroxidase activities. Waterlogging increased the concentration of Na and reduced concentrations of K. Reductions in root Ca were also recorded. GB enhanced growth, concentration of chlorophyll and activities of superoxide dismutase, catalase, and peroxidase that in turn protected the plants from oxidative damage. GB decreased Na while increasing leaf and root K and stem and fruit Ca under waterlogging. Waterlogging reduced fruit quality. There was decrease in protein, fat, and total dissolved solids and an increase in fruit moisture, P, and Na in plants under waterlogging. GB enhanced fruit quality largely by improving fruit protein, ash, fat, TDS, and Ca, while it decreased fruit Na. The results of this study suggest the use of GB for commercial production of tomato where waterlogging is likely.     

外源甜菜碱对盐胁迫下加工番茄生理特性的影响

研究了外源甜菜碱对加工番茄幼苗抗盐性的影响。结果表明:外源甜菜碱可以显著提高加工番茄叶片中脯氨酸和可溶性糖含量,可以提高加工番茄叶片SOD活性,降低膜透性和MDA的含量,从而有效的提高加工番茄的抗盐性。在该试验中叶面喷施高浓度的甜菜碱比低浓度的甜菜碱效果更明显。     

核果类果树转基因研究进展

综述了近年来国内外核果类果树转基因的研究进展,涉及的内容有:用农杆菌转化核果类果树中难生根种类,获得易繁殖的转化植物;转移病毒外壳蛋白基因和杀菌毒性肽基因以提高抗病性;转移细胞分裂素基因和光敏素基因改良品种或砧木生长特性,培育紧密型的、短枝的、矮化半矮化的新品种;转移抗冻基因提高抗霜冻性;通过反义转基因技术调节果实的成熟,获得耐贮运的新性状,以及核果类果树基因转化技术的发展等方面。     

外援抗氧化剂对高温胁迫下红地球葡萄果实日灼的影响

以红地球葡萄为试材,通过施用抗坏血酸(AsA)、苯甲酸钠(SBN)和氯化钙(CaCl2),研究不同种类外源抗氧化剂对高温胁迫下果皮组织对丙二醛(MAD)含量、相对电导度(REC)、过氧化氢酶(CAT)和抗坏血酸-过氧化物酶(APX)活性的影响,比较几种抗氧化剂对提高果实抗氧化能力的效果。结果表明:在高温胁迫下,以施用0.03 mol/L抗坏血酸0、.02 mol/L苯甲酸钠和0.10%氯化钙后,能显著和极显著地降低膜脂过氧化产物MDA的含量,保持膜结构及功能相对稳定性,提高果实CAT和APX酶活性,从而提高了果实抗日灼的能力。     

Responses of field grown tomato plants to arbuscular mycorrhizal fungal colonization under varying intensities of drought stress

The effects of root colonization by the arbuscular mycorrhizal (AM) fungus Glomus intraradices Schenck and Smith on growth, flower and fruit production, and fruit quality were studied in field-grown tomato plants exposed to varying intensities of drought stress. Inoculated (M+) and non-inoculated (M−) tomato seedlings were exposed to varying intensities of drought stress by adjusting irrigation intervals. Mycorrhizal plants had significantly higher uptake of N and P in both roots and shoots regardless of intensities of drought stress. AM inoculation also significantly increased shoot dry matter and the number of flowers and fruits. The fruit yields of M+ plants under severe, moderate, mild drought-stressed conditions were higher than M− plants by 24.7%, 23.1%, 16.2% and 12.3%, respectively. Furthermore, M+ plants produced tomato fruits that contain significantly higher quantities of ascorbic acid and total soluble solids (TSS) than M− plants. Mycorrhizal effects increased with increasing intensity of drought. The overall results suggest that mycorrhizal colonization affects host plant nutritional status, water stratus and growth under field conditions and thereby alters reproductive behaviour, fruit production and quality of fruits under both well-watered and drought-stressed conditions.     

农杆菌介导三价融合基因Rirol转化八棱海棠的研究

研究了以口蹄疫病毒FMDV 2A序列融合多基因在八棱海棠遗传转化上的应用,将DREB,IRT1和rolC融合三价基因(Rirol)通过农杆菌介导法转化八棱海棠,获得了一批nptⅡ抗性植株,经报告基因检测、PCR和Southern杂交分析证明融合基因成功导入到八棱海棠中。对转基因八棱海棠相关性状分析表明,转基因八棱海棠比对照具有较强的耐盐性,在表型上,表现节间缩短,分枝性强,侧根发达,证明外源融合基因在转基因植株中得到表达。试验初步证明了利用FMDV 2A序列进行多基因转化八棱海棠的可行性,为苹果等果树多基因转化提供了新的思路和途径。