离体条件下外源茉莉酸甲酯对人参锈腐病菌的影响

人参(Panax ginseng)是我国传统的名贵药材,由毁灭柱孢(Cylindrocarpon destructans)引起的人参锈腐病是严重影响人参产量和品质的重要根部病害之一,在人参生产中会造成严重的经济损失.茉莉酸甲酯(methyl jasmonate,MeJA)是一类新型的生长调节物质,既可以参与植物对病原菌及其他逆境胁迫做出的应答并进行信号传递,又可用来诱导植物的抗病反应.为了明确MeJA对人参锈腐病菌的影响并解析MeJA与病原菌致病因子之间的相互关系,该文研究了外源MeJA在不同浓度下对C.destructans的直接影响,包括对菌落生长、孢子萌发、菌丝生长量、病菌分泌水解酶的影响.结果表明:MeJA能够强烈抑制病原菌的生长和孢子萌发,而对病原菌致病酶的活性则表现出促进作用;人参锈腐病菌在PDA平板上的菌落直径从(8.23±0.15) cm(对照)减少到(0.71±0.00) cm(800 μg·mL-l MeJA),在MeJA浓度达到最高时,菌落生长几乎完全被抑制;MeJA的浓度大于400 μg·mL-1时,病原菌的生物量减少了65.3％～ 100％,孢子萌发率和芽管长度减少了100％;MeJA在浓度大于200 μg·mL-1时,果胶酶、纤维素酶和淀粉酶活性升高而蛋白酶的活性却没有变化.综上表明,MeJA对病原菌产生抑制作用的临界浓度为200 μg·mL-1.该研究结果为后续使用MeJA处理人参植株进行诱导抗病性的研究奠定了基础,同时也有助于进一步了解人参锈腐病的致病机理,并为病害防控提供了理论参考.     

离体条件下外源茉莉酸甲酯对人参锈腐病菌的影响（英文）

人参(Panax ginseng)是我国传统的名贵药材,由毁灭柱孢(Cylindrocarpon destructans)引起的人参锈腐病是严重影响人参产量和品质的重要根部病害之一,在人参生产中会造成严重的经济损失。茉莉酸甲酯(methyl jasmonate,Me JA)是一类新型的生长调节物质,既可以参与植物对病原菌及其他逆境胁迫做出的应答并进行信号传递,又可用来诱导植物的抗病反应。为了明确Me JA对人参锈腐病菌的影响并解析Me JA与病原菌致病因子之间的相互关系,该文研究了外源Me JA在不同浓度下对C.destructans的直接影响,包括对菌落生长、孢子萌发、菌丝生长量、病菌分泌水解酶的影响。结果表明:Me JA能够强烈抑制病原菌的生长和孢子萌发,而对病原菌致病酶的活性则表现出促进作用;人参锈腐病菌在PDA平板上的菌落直径从(8.23±0.15)cm(对照)减少到(0.71±0.00)cm(800μg·m L~(-1)Me JA),在Me JA浓度达到最高时,菌落生长几乎完全被抑制;Me JA的浓度大于400μg·m L~(-1)时,病原菌的生物量减少了65.3%~100%,孢子萌发率和芽管长度减少了100%;Me JA在浓度大于200μg·m L~(-1)时,果胶酶、纤维素酶和淀粉酶活性升高而蛋白酶的活性却没有变化。综上表明,Me JA对病原菌产生抑制作用的临界浓度为200μg·m L~(-1)。该研究结果为后续使用Me JA处理人参植株进行诱导抗病性的研究奠定了基础,同时也有助于进一步了解人参锈腐病的致病机理,并为病害防控提供了理论参考。     

人参(Panax ginseng)根系分泌物成分对人参致病菌的化感效应

采用室内培养结合生物学测定的试验方法,研究了不同浓度人参(Panax ginseng)根系分泌物成分苯甲酸、邻苯二甲酸二异丁酯、十六酸和2,2-二(4-羟苯基)丙烷对人参立枯丝核菌(Rhizoctonia solani)、黑斑菌(Alternaria panax)、疫病菌(Phytophthora cactorum)、菌核菌(Sclerotinia schinseng)、锈腐菌(Cylindrocarpon destructans)和绿色木霉菌(Trichoderma viride)菌落生长及孢子萌发的化感效应.结果显示,不同浓度人参根系分泌物成分对人参致病菌及绿色木霉菌的化感效应存在显著差异.苯甲酸浓度与人参立枯丝核菌、菌核菌和锈腐菌菌落生长以及人参黑斑菌、锈腐菌孢子萌发呈负相关,与人参黑斑菌、绿色木霉菌菌落生长呈正相关;对人参疫病菌菌落生长的化感效应表现为低浓度和高浓度抑制,中浓度促进.邻苯二甲酸二异丁酯浓度与人参立枯丝核菌、黑斑菌、菌核菌和绿色木霉菌菌落生长以及人参黑斑菌孢子萌发呈负相关;对人参锈腐菌菌落生长和孢子萌发表现为低浓度和高浓度抑制,中浓度促进;对人参疫病菌菌落生长表现为低浓度和中浓度抑制,高浓度促进.2,2-二(4-羟苯基)丙烷浓度与人参立枯丝核菌、黑斑菌、疫病菌、绿色木霉菌菌落生长以及人参黑斑菌、锈腐菌孢子萌发呈负相关;对人参菌核菌、锈腐菌菌落生长表现中浓度促进,高浓度抑制.十六酸浓度与人参锈腐菌、疫病菌和绿色木霉菌菌落生长呈正相关,与人参锈腐菌孢子萌发呈负相关,对黑斑菌孢子萌发表现为中浓度抑制.4种根系分泌物的等量混合物浓度与人参致病菌及拮抗木霉菌菌落生长速率呈负相关.     

人参连作根际土壤中酚酸物质对人参锈腐病菌的化感效应

采用高效液相色谱法对人参连作根际土壤中的酚酸物质进行了分离鉴定,检测发现人参根际土壤中含有没食子酸、水杨酸、3-苯基丙酸、苯甲酸和肉桂酸5种酚酸物质.采用外源添加法研究该5种酚酸物质对人参锈腐病菌的化感效应.结果表明: 5种酚酸对人参锈腐病菌的菌丝生长和孢子萌发都表现出高浓度抑制、低浓度促进的作用.没食子酸、水杨酸和苯甲酸在0.5 mmol·L^-1处理浓度下,3-苯基丙酸和肉桂酸在0.05 mmol·L^-1处理浓度下,均能够显著促进人参锈腐病菌菌丝生长和孢子萌发,并显著加重人参锈腐病病害严重度.     

人参锈腐病斑的扫描电镜观察

采用半薄切片,应用扫描电镜观察了人参锈腐病菌的侵染状况,从人参病斑分离出的病原菌经鉴定属于柱孢菌属(CYlindrocarpon)。     

应用11371复合剂防治人参锈腐病的研究

人参锈腐病是栽培参的主要病害,发病率一般在60—80％,对栽培参的损失很大。由于该病是土传病害,而且致病菌复杂,多年来尚无较好的防治方法。本文介绍了使用抗生素11371为主的复合药剂防治人参锈腐病的情况;几年来田间防效稳定在45％以上,最高防效可达70％,并且用药当年可增产15％左右。     

生物促腐剂对烤烟生长发育、产量和质量的影响

本研究以牛栏粪和HM腐熟剂为材料,研究了生物促腐剂的应用对烟株生长和品质的影响。研究结果表明,T2处理茎围较对照(CK)增加0.4cm,较T1处理增加0.5cm,均达到了差异显著水平;T2处理上部叶叶面积较对照(CK)增加131.9cm,中部叶较T1处理增加117.6cm。相对于T1处理,生物促腐剂的应用明显减轻病害发生程度,其中T2和T3处理烟株青枯病和黑胫病发病率和病情指数明显下降,普通花叶病毒病发生程度也有所减轻;总糖和还原糖含量分别增加1.6%～3.0%和2.0%～3.5%,总植物碱含量降低0.13%～0.17%,糖碱比更趋协调。生物促腐剂的应用对烟株前期生长无明显影响,但对烟株后期生长的促进作用较为明显,因此,生物促腐剂腐熟剂1号的应用在一定程度上能够促进烟株生长,明显减轻病害发生程度,协调烟叶内在化学成分,改善烟叶评吸质量。     

内生菌株B16发酵条件优化及其对人参锈腐病的防效

【目的】优化人参病害拮抗菌株B16的发酵条件,提高发酵液的活菌含量和抗菌活性,检测该菌对人参病害的防效。【方法】采用单因子试验、正交试验优化菌株B16的发酵培养基及发酵条件,于室内盆栽条件下研究其对人参锈腐病的防效。【结果】菌株B16发酵最适培养基为:蔗糖1.00%、酵母膏0.50%、Mg SO4·7H2O 0.05%、Fe SO4·7H2O 0.06%、Na Cl 1.00%;最佳发酵条件:p H 7.5、温度35°C、接种量5%、装液量40 m L/250 m L、摇床转速170 r/min、发酵周期48 h。菌株B16发酵液对人参锈腐病的保护作用和治疗作用防效分别达到64.8%和58.6%。【结论】菌株B16具有很强的生防潜力。     

人参与病原菌互作代谢产物醇溶性主成分分析

采用营养液培养的方法研究了病原菌侵染对生长初期人参根系分泌物收集物组成的影响,分别从对照及菌核菌、疫霉菌、立枯丝核菌、锈腐菌诱导处理的根系分泌物收集物中检测到27、23、17、16和20种主成分,并用标准化合物对其中的11、6、6、3和9种化合物进行了验证。结果表明：病原菌诱导后人参根系分泌物收集物主成分数量明显减少;收集物中化合物类型也发生了明显变化,新增化合物多为有机酸酯、苯及酚酸类衍生物,而减少的化合物无明显规律。     

人参与病原茵互作代谢产物醇溶性主成分分析

采用营养液培养的方法研究了病原菌侵染对生长初期人参根系分泌物收集物组成的影响,分别从对照及菌核菌、疫霉菌、立枯丝核菌、锈腐菌诱导处理的根系分泌物收集物中检测到27、23、17、16和20种主成分,并用标准化合物对其中的11、6、6、3和9种化合物进行了验证.结果表明:病原菌诱导后人参根系分泌物收集物主成分数量明显减少;收集物中化合物类型也发生了明显变化,新增化合物多为有机酸酯、苯及酚酸类衍生物,而减少的化合物无明显规律.     

豚草锈菌对三裂叶豚草叶片生理生化特性的影响

【背景】自20世纪50年代三裂叶豚草传入我国以来,迅速蔓延,已给我国农业生产、生态环境、人民健康造成巨大威胁。近年来发现的豚草锈菌对三裂叶豚草有一定的致病性,具备生物防治潜力。【方法】本文利用植物生理学技术研究了豚草锈菌对三裂叶豚草叶片生理生化特性的影响。【结果】锈菌侵染后,三裂叶豚草叶片的相对电导率随病级的增高和侵染时间的延长而上升,说明锈菌破坏了豚草叶片的细胞膜,导致其电解质外渗。同时,发病初期叶片内的丙二醛(MDA)与超氧自由基(O2.-)含量逐渐上升;当发病程度为3级时,O2.-含量达到最高;4级时,MDA含量达到最高。此外,锈菌侵染后,三裂叶豚草叶片抗坏血酸(AsA)含量持续上升,而脯氨酸(Pro)含量在发病后期下降,说明在三裂叶豚草与锈菌互作时,AsA含量虽然增加,但抗性并不明显,而Pro可能具有更为重要的作用。【结论与意义】豚草锈菌的侵入干扰了三裂叶豚草的生理生化反应,这将为深入研究豚草锈菌的致病机理、发挥其生物防治潜力奠定基础。     

Effects of zinc toxicity on sugar beet (Beta vulgaris L.) plants grown in hydroponics

The effects of high Zn concentration were investigated in sugar beet ( Beta vulgaris L.) plants grown in a controlled environment in hydroponics. High concentrations of Zn sulphate in the nutrient solution (50, 100 and 300 μ m ) decreased root and shoot fresh and dry mass, and increased root/shoot ratios, when compared to control conditions (1.2 μ m Zn). Plants grown with excess Zn had inward-rolled leaf edges and a damaged and brownish root system, with short lateral roots. High Zn decreased N, Mg, K and Mn concentrations in all plant parts, whereas P and Ca concentrations increased, but only in shoots. Leaves of plants treated with 50 and 100 μ m Zn developed symptoms of Fe deficiency, including decreases in Fe, chlorophyll and carotenoid concentrations, increases in carotenoid/chlorophyll and chlorophyll a / b ratios and de-epoxidation of violaxanthin cycle pigments. Plants grown with 300 μ m Zn had decreased photosystem II efficiency and further growth decreases but did not have leaf Fe deficiency symptoms. Leaf Zn concentrations of plants grown with excess Zn were high but fairly constant (230–260 μg·g⁻¹ dry weight), whereas total Zn uptake per plant decreased markedly with high Zn supply. These data indicate that sugar beet could be a good model to investigate Zn homeostasis mechanisms in plants, but is not an efficient species for Zn phytoremediation.     

Quantitative proteomics of Arabidopsis shoot microsomal proteins reveals a cross‐talk between excess zinc and iron deficiency

Iron (Fe) deficiency significantly effects plant growth and development. Plant symptoms under excess zinc (Zn) resemble symptoms of Fe‐deficient plants. To understand cross‐talk between excess Zn and Fe deficiency, we investigated physiological parameters of Arabidopsis plants and applied iTRAQ‐OFFGEL quantitative proteomic approach to examine protein expression changes in microsomal fraction from Arabidopsis shoots under those physiological conditions. Arabidopsis plants manifested shoot inhibition and chlorosis symptoms when grown on Fe‐deficient media compared to basal MGRL solid medium. iTRAQ‐OFFGEL approach identified 909 differentially expressed proteins common to all three biological replicates; the majority were transporters or proteins involved in photosynthesis, and ribosomal proteins. Interestingly, protein expression changes between excess Zn and Fe deficiency showed similar pattern. Further, the changes due to excess Zn were dramatically restored by the addition of Fe. To obtain biological insight into Zn and Fe cross‐talk, we focused on transporters, where STP4 and STP13 sugar transporters were predominantly expressed and responsive to Fe‐deficient conditions. Plants grown on Fe‐deficient conditions showed significantly increased level of sugars. These results suggest that Fe deficiency might lead to the disruption of sugar synthesis and utilization.     

叶面配施镁锌钼对银杏苗叶生长和药用品质的影响

以两年生银杏苗为研究对象,采用室内模拟与盆栽试验相结合的方法,研究了叶面配施低、中、高浓度的镁、锌、钼对银杏叶产量和药用成分含量及其产量的影响,以明确叶用银杏叶面微肥中镁锌钼的适宜浓度。结果显示:(1)镁锌钼配施能提高单叶面积、叶片厚度、单株叶面积和叶生物量,并以配施组合Mo3(2%Mg+0.3%Zn+0.1%Mo)对叶生物量的提高幅度较大(64.9%)。(2)中锌中钼配施镁肥对银杏叶绿素、可溶性糖和可溶性蛋白质含量的正效应随着镁肥喷施浓度的增加而降低,中镁中钼配施锌肥、中镁中锌配施中钼对叶片叶绿素、可溶性糖含量的正效应随着配施肥料浓度的升高而降低,而可溶性蛋白含量与配施肥料浓度呈正相关。(3)镁锌钼配施能提高叶片总黄酮、萜内酯含量,以及单株总黄酮和萜内酯产量,以配施组合Mo3对单株总黄酮、萜内酯产量的提高幅度最大,分别为2.96倍和1.70倍。(4)配施高浓度的肥料(Mg4、Zn4和Mo4)不同程度地降低了镁锌钼配施对部分指标的正效应。研究表明,配施适当浓度的镁锌钼叶面肥可在一定程度促进银杏苗叶绿素合成,上调可溶性糖和可溶性蛋白质等初生代谢物质积累,改善其叶片生长和药用品质,提高叶产量及药用品质构成要素;微肥2%Mg+0.3%Zn+0.1%Mo是本试验条件下提高银杏叶产量、药用成分含量和产量较为理想的叶肥组合。     

茶叶主要化学品质指标和茶树体部分微量元素的钙铝调控效应

以一年生茶树扦插苗为材料,采用水培法研究了添加钙铝对茶叶主要化学品质及茶树钙、铝、锌、铁吸收积累的调控效应.结果表明:(1)适量铝(10或20mg·L-1)有利于提高茶叶茶多酚、咖啡碱、黄酮、可溶性总糖和氨基酸的含量;添加钙可提高上述化学成分的含量,且在高铝浓度(30mg·L-1)下提高的幅度最大.(2)适量的铝可促进茶树对铝和铁的吸收和积累,而高浓度的铝(30mg·L-1)抑制茶树对铝和铁的吸收与积累;添加铝可降低茶树根对钙和锌的吸收,但适量添加铝不影响茎和叶对钙和锌的积累.(3)添加钙可提高茶树体钙的含量,降低铝和锌的吸收与积累,但对铁的吸收与积累没有明显影响.研究表明,铝和钙可调控茶叶化学品质含量和茶树体微量元素的吸收;合理控制茶园土壤铝积累,并适量补充钙可能有利于提高茶叶品质,创建生态高值茶园.     

条形柄锈菌小麦专化型脂肪酶基因PsLIP1的酶学性质分析

脂肪作为条形柄锈菌小麦专化型夏孢子萌发及侵染初期的主要营养物质,酶解产物通过乙醛酸循环转化为糖类成分供病菌生长发育所需。脂肪酶是脂肪代谢的关键酶。基于已测序的基因组序列,利用RT-PCR方法克隆了该病菌脂肪酶基因PsLIP1序列（1 302bp）,编码433个氨基酸的蛋白。在毕赤酵母细胞（GS115）中成功表达PsLIP1后,酶学活性分析显示其最适pH为8.0,最适温度为60℃,此外,发现Zn²⁺、Cu²⁺和Ca²⁺对脂肪酶PsLIP1活力有一定激活作用,Fe²⁺、Mn²⁺则对酶活力有抑制作用。研究结果为进一步解析脂肪酶作用机理奠定基础,同时也为从能量代谢角度制定小麦条锈病防控策略提供理论依据。     

Plant response and huanglongbing disease development against heat treatments on ‘Siam Purworejo’ (Citrus nobilis (Lour)) and ‘Nambangan’ (C. maxima (Burm.) Merr.) under field condition

Huanglongbing is known as a destructive disease in citrus production. Investigation on plant response and development of huanglongbing disease against heat treatment on ‘Siam Purworejo’ (Citrus nobilis (Lour)) and ‘Nambangan’ (C. maxima (Burm.) Merr.) was done. High-temperature treatment was applied by covering plants with an enclosed screen. The treatment plant has three types of CLas pathogen infection status. The result showed that heat treatments could significantly increase new flushes. It was found that intensity of HLB infected plant decreased. The treatments effect on the proline level was dependent on cultivar, leaves age and HLB-infection status. Chlorophyll content of HLB infected plants increased due to high temperature. High-temperature increased Fe content in the artificially infected plant, whereas Zn contents increased in the leaves of infected plants by vector. ‘Nambangan’ had higher Fe content than ‘Siam Purworejo’ on uncovered plants. CLas bacteria still persisted in infected plant based on real-time PCR analysis.     

Zinc-alleviating effects on iron-induced phytotoxicity in roots of <Emphasis Type="Italic">Triticum aestivum</Emphasis>

The mechanisms of growth inhibition and antioxidative response were investigated in wheat roots exposed to 300 μM iron together with different zinc concentrations (0, 50, and 250 μM). All Zn concentrations decreased Fe content but increased Zn content in the roots and leaves of Fe-treated seedlings. Compared with Fe stress alone, 50 or 250 μM Zn + Fe treatment stimulated root growth, and increased cell viability but decreased malondialdehyde content, which were correlated with the decreases of total and apoplastic hydrogen peroxide and superoxide anion radical (O₂ ^·?) content along with apoplastic hydroxyl radical content. Generation of O₂ ^·? in response to 10 μM diphenylene iodonium suggested that NADPH oxidase activity was lower in Zn + Fe-treated roots than in other roots. In addition, cell wallbound peroxidase, diamine oxidase, and polyamine oxidase in Fe-treated roots were insensitive to Zn addition. Further study showed the stimulation of total superoxide dismutase and glutathione reductase (GR) activities as well as apoplastic catalase, ascorbate peroxidase, and GR in Zn + Fe-stressed roots in comparison with Fe-alone-treated ones. Taken together, Zn could alleviate iron-inhibitory effect on root growth, which might be associated with the decrease of lipid peroxidation, the increase of cell viability and the reductions of reactive oxygen species generation.     

Levels of Selected Trace Elements, Phytohormones, and Sugars in Pseudomonas-Infected Lycopersicum esculantum Mill Plants

The present study investigated the levels of trace elements (Zn, Cu, Fe, Pb, and Cd), major elements (Ca and K), phytohormones (trans-Zeatin [t-Z] and gibberellic acid [GA]), and sugars (sucrose and glucose) following inoculation with Pseudomonas syringae pv. tomato strain. The results of the trace elements analysis showed that Fe (in the first, fourth, eighth, and tenth study days), Cd (in the fourth, eighth, and tenth study days), Cu (in the fourth and eighth study days), and Zn (in the eighth and tenth study days) increased in bacterium-infected tomato plants, compared to healthy plants. The levels of Pb, Ca, and K did not meaningfully determine a change after inoculation with pathogen. In this vein, the increase accumulation rates of Cu, Zn, and Fe in the injured plants can be an important indicator for the plant defense processes towards pathogen attack. Furthermore, in the first, fourth, eighth, and tenth study days, the glucose and sucrose contents crucially decreased in bacterium-infected plants compared to the control groups. The lowest level of sucrose in bacterium-infected plants was observed on the first day. The findings displayed that, when endogenous t-Z levels did not change after inoculation with virulent bacterium strain, there was a reduction in the first, fourth, eighth, and tenth days in the level of GA when compared with the control group levels. Therefore, there may be a link between lower GA level and enhancement in the expression of defense-related genes. The results of this study showed that there are complex relationships among levels of sugar, trace element, and endogenous phytohormone in the regulation of defense mechanisms against bacterial pathogen attacks.