水杨酸诱导植物抗病性机制的研究进展

水杨酸(SA)是诱导植物抗性的信号分子,可通过诱导植物产生病程相关蛋白(PR蛋白)、调节相关保护酶活性等途径使植物体产生系统获得性抗性(SAR)。SA与具有过氧化氢酶(CAT)活性的水杨酸受体蛋白(SABP)结合后,抑制其CAT活性,导致细胞内过氧化氢(H2O2)浓度升高,H2O2作为第二信使激活植物体内抗性基因的表达。植物体内SA积累使病程相关基因非表达子1(NPR1)低聚体水解还原成单体NPR1后,通过与转录因子相互作用诱导病程相关基因的表达。SA作为信号分子在植物体内的运输、SA合成相关基因及其上调转录因子转化植株后对其抗病性的影响以及SA激活NPR1基因表达的具体方式将是今后的研究重点。     

NPR1调控植物抗病机制及功能研究进展

NPR1是植物防御信号转导途径的重要调控因子，是不同形式抗病信号转导途径中的交叉点之一，在系统获得抗性和诱导系统抗性中起核心调控作用。目前对其在系统获得抗性中的调控机制开展了广泛和深入的研究。在多种植物中过表达NPR1基因提高了植物的抗病性。阐述了目前NPR1基因在植物中调节抗病性的作用机制，论述了在植物中转NPR1基因的抗病功能，对今后更加深入全面研究NPR1基因，利用NPR1基因提高植物抗病性进行了展望。     

水杨酸处理对水稻过氧化物酶比活的影响

水杨酸可诱导植物系统获得抗性。本文研究表明：水杨酸诱导处理２４小时后,水稻植株体内过氧化物酶比活急剧上升,处理４８小时后,酶比活力相应对照的３倍左右,并且能保持高水平的比活。这对于水稻植株建立对多种病菌侵入的广谱抗性极具重要意义。     

水杨酸处理对水稻过氧化物酶比活的影响

水杨酸可诱导植物系统获得抗性。本文研究表明：水杨酸诱导处理２４小时后，水稻植株体内过氧化物酶比活急剧上升，处理４８小时后，酶比活为相应对照的３倍左右，并且能保持高水平的比活。这对于水稻植珠建立对多种病菌侵的广谱抗性极具重要意义。     

马铃薯抗晚疫病和病毒病转基因研究现状与展望

从Harpin蛋白基因表达诱导抗性、Osmotin蛋白诱导抗性、病原诱导葡萄糖氧化酶(GO)基因表达生成H2O2获得抗性途径对抗马铃薯晚疫病抗性转基因研究现状进行了综述;从病毒外壳蛋白(CP)基因介导抗病性、复制酶基因介导抗病性、用核酶切割介导抗病性、病毒基因调控序列介导抗性途径对马铃薯病毒病抗性转基因研究现状进行了综述。     

香蕉系统获得抗性相关基因对外源水杨酸的响应分析

香蕉生产受多种病虫害和逆境胁迫的影响,由真菌病原引起的香蕉枯萎病、叶斑病和黑星病,细菌性病害软腐病和鞘腐病,以及非生物胁迫寒害等,是阻碍香蕉绿色可持续生产的严重问题.为探索香蕉生产上多种病害和寒害逆境的有效防控措施,本研究从外源水杨酸(SA)诱导植物系统抗性机理出发,通过实时荧光定量PCR(RT-qPCR)方法,分析外...     

水杨酸处理对花生主要防御酶活性的影响

用不同浓度水杨酸(SA)处理花生植株,然后测定不同时间花生叶片中,苯丙氨酸解氨酶(PAL)、多酚氧化酶(PPO)、过氧化物酶(POD)等主要防御酶活性的变化。结果表明,水杨酸处理花生叶片可明显诱导花生防御酶活性提高,且以7.5 mmol/L浓度水杨酸的作用效果最为显著,各种防御酶在24~48h内逐渐被诱导达到活性高峰。外源水杨酸诱导花生防御酶活性提高,使花生获得系统抗性。     

小麦PR-1、PR-2、PR-5基因的白粉菌和水杨酸诱导表达分析及白粉病抗性研究

病程相关蛋白基因PR-1、PR-2和PR-5是植物抗病基因介导的抗病反应和系统获得抗性(systemic acquired resistance,SAR)中的标志基因。为了研究病程相关蛋白基因和水杨酸在小麦(TriticumaestivumL.)抗白粉病反应中所起的作用,以抗白粉病和感白粉病小麦品系为材料,在白粉病菌(Blumeria graminisf.sp.tritici,Bgt)诱导不同时间,或水杨酸处理不同时间后,用半定量RT-PCR技术检测了小麦叶片中PR-1、PR-2和PR-5基因的表达变化。结果表明,白粉病菌的侵染激活和显著增强了病程相关蛋白基因PR-1、PR-2和PR-5在周麦18中的转录。与感病品系相比,PR-1和PR-5在抗病品系中转录激活得更快、更强。水杨酸处理显著激活了PR-1和PR-5的转录,但对PR-2的转录影响不大。白粉病菌和水杨酸均能显著激活和增强PR-1和PR-5的表达,但白粉病菌的作用更强,说明PR-1和PR-5基因在小麦抗白粉病反应中起重要作用。PR-1和PR-5可以作为小麦SAR的标志基因。水杨酸处理后周麦18和中国春的白粉病抗性得到提高,提示水杨酸在小麦抗白粉病信号传导途径中起一定作用。     

水杨酸和壳聚糖诱导大豆对灰斑病的抗性

植物诱导抗病性是植物保护的一项新措施,灰斑病是大豆的重要病害之一,目前生产中主要是推广抗病品种进行预防.而有关诱导大豆抗灰斑病的研究报道极少,本研究主要是利用两种常见的化学诱导因子来探讨对大豆抗灰斑病的诱抗效果,为进一步开发高效、安全、环保的诱抗剂奠定理论基础.选用水杨酸(SA)和壳聚糖两种诱抗剂处理感病品种黑农35和中抗品种东农42,当大豆第4片复叶完全展开时,分别在当天和以后的5,10 d对大豆植株进行不同的诱导处理.结果表明,当水杨酸浓度为1 000 mg·L-1时连续叶喷三次,使黑农35和东农42的诱抗效果分别达到了72.2%和66.7%;浓度为1 000 mg·L-1的壳聚糖叶喷对黑农35和东农42的诱抗效果分别达到了72.2%和55.6%;而10 000 mg·L-1壳聚糖溶液浸种与1 000 mg·L-1壳聚糖溶液叶喷混用对于黑农35和东农42诱导作用最强,诱抗效果分别可达88.9%和72.2%.说明水杨酸和壳聚糖均能够诱导大豆品种(黑农35和东农42)对灰斑病产生较高的抗性.诱抗效果因所用试剂的浓度及作物品种而异,施用方法以及施用次数也影响诱抗效果,水杨酸在适宜浓度下对黑农35的诱抗效果明显高于东农42.     

化感物质对植物生长的影响及其在茶叶生产中的应用

化感物质通过化感作用对植物的生长发育起抑制或促进作用，诱导植物产生直接抗性或间接抗性，从而对植物的生长造成影响。这种作用在茶叶生产中具有重要的现实意义和广阔的应用前景。     

寡糖诱导向日葵抗锈病的信号转导途径

为了解寡糖诱导向日葵抗锈病过程中的信号转导途径,利用寡糖、水杨酸（SA）、茉莉酸（JA）预先喷雾处理向日葵叶片,1d后接种锈菌,通过对植株体内脂氧合酶（LOX）活性及SA含量的测定,并通过RT-PCR对SA、JA信号途径的标记基因PR5和PDF1.2等表达水平进行测定,初步确定诱导抗性表达的信号转导途径。结果表明：经寡糖诱导后,向日葵叶片内LOX活性降低,SA含量上升,且诱导水杨酸途径标记基因PR5表达量增加。结果说明寡糖诱导向日葵抵抗锈病主要与SA介导的信号途径有关。     

外源信号物质诱导人参抗人参锈腐病的作用研究

探讨外源水杨酸(SA)茉莉酸甲酯(MeJA)诱导人参抗锈腐病的效果,以期通过施入外源物质来提高人参植株的抗性.测定了0～800mg·L-1不同浓度SA和MeJA溶液对人参锈腐病菌的影响,利用筛选的浓度(200 mg· L-1)处理二年生人参移栽苗,接种人参锈腐菌,调查人参锈腐病的发病率和病害严重度.结果表明,浓度为200 mg· L-1的SA和MeJA溶液对人参锈腐病菌无直接毒害作用,而经SA和MeJA处理的人参植株锈腐病发病率和病害严重度显著降低,SA的诱抗效果优于MeJA.     

Induction of resistance to root-knot nematodes by SAR elicitors in tomato

Different concentrations of the systemic acquired resistance (SAR) elicitors, salicylic acid (SA), methyl-salicylic acid (MetSA), acibenzolar-S-methyl (ASM) and 2,6-dicholoroisonicotinic acid (INA), were provided to tomato seedlings as root-dip or soil-drench one day before inoculation with the root-knot nematode, Meloidogyne incognita. Nematode infestation was evaluated by counting egg masses/plant (EM), eggs/plant (Pf), and sedentary forms/plant (SF) in treated and untreated plants seven weeks after inoculation. An index of plant fitness (PF) was also calculated to assess the costs of chemically-induced resistance and the possible phytotoxicity of the treatments. SA and ASM were found to be effective elicitors of resistance when applied at suitable concentrations and method of application. Soil-drench with SA and root-dip in ASM were the most effective treatments as they markedly reduced both nematode reproduction (less than 50% that of untreated plants) and infestation (50–70% EM reduction). MetSA was less effective than SA in eliciting resistance because of its negative effects on plant fitness when it was provided as soil-drench. INA did not reduce nematode infestation at any of the non-phytotoxic rates. The reduction of nematode infestation and reproduction by SA applied as soil-drench was potentiated when the soil was enriched with humic acids. Soil-drenching with SA and MetSA were the only treatments that caused a long-lasting induction of plant defences as they inhibited the infestation by the second generation of the nematode.     

Responses of soybean genotypes to pathogen infection after the application of elicitors

Soybean diseases and pests can affect soybean production. One emerging pest management method is to treat plants with chemical elicitors at nontoxic levels to induce host resistance. The objective of this research was to determine if elicitors, benzothiadiazole (BTH), chitosan (CHT), phenylalanine (PHE), and salicylic acid (SA), applied to soybean foliage could alter the response of soybean genotypes to soybean pathogens. Two of the soybean genotypes had been previously shown to produce high or low amounts of reactive oxygen species (ROS) in response to elicitation. In the greenhouse, soybean genotypes were challenged with three pathogens 48 h after elicitation. Plants of the cultivar Pharaoh (susceptible control) treated with SA, and then inoculated with Macrophomina phaseolina had a shorter (α = 0.05) stem lesion length (34 mm) than the water control (55 mm). Plants of soybean genotype LD00-2817p (high capacity to produce ROS) and the cultivar Sloan treated with BTH, PHE, or SA, and then inoculated with Phytophthora sojae had greater (α = 0.05) survival rates than plants treated with the water control. The four elicitors and a water control were evaluated on LD00-2817p and LDX01-1-65 in the field for two consecutive years. Foliar disease incidence and severity were low for both years, although there were some differences in stem disease ratings. For example, charcoal rot stem severity rating was reduced (α = 0.05) from 2.0 in the water control to 1.1 with a PHE treatment for LD00-2817p and was reduced (α = 0.05) from 3.8 in the water control to 2.6 with SA for LDX01-1-65 in 2013. Both greenhouse controlled experiments and field experiments showed that genotype-specific elicitation reduced disease severity in some cases, but the differences were greater under controlled-inoculated conditions.     

Effects of salicylic acid on growth, biochemical constituents in pepper (Capsicum annuum L.) seedlings

In the present study, the effect of different concentrations of salicylic acid which is an endogenous organic acid in plants and which is commonly cited as a hormone, on the growth and some other parameters of pepper (Capsicum annuum L. cv.) seedlings was investigated. The solutions were applied to the roots of seedlings using hydroponic method. In general, 1.5 mM concentration of salicylic acid had a stimulating effect while 5 and 10 mM concentrations had varying degrees of inhibitive effects on the seedlings. Although 0.3 mM SA application produced prominent results in the case of all parameters, the difference was not found statistically significant. The inhibitive effect produced by high SA was found much more dominant than the stimulating effect of low SA concentrations. Thus, it was established that SA had a bidirectional physiological effect on the seedlings in a concentration-dependent manner.     

水分胁迫下外源水杨酸对毛豆某些生理指标及其抗旱性的影响（简报）

在水分胁迫下采用不同浓度的水杨酸对毛豆(Glycine max)幼苗进行叶面喷施处理,测定其对毛豆幼苗某些生理指标及其抗旱性的影响.结果表明:采用适当浓度的水杨酸处理可以提高根系活力和叶绿素含量、降低细胞膜透性及丙二醛含量,增强了毛豆幼苗对干旱环境的抵抗能力.从叶面喷施对毛豆的生理指标进行综合判断可知:在试验的范围内,以0.1 mmol/L的水杨酸处理效果为最佳.     

甘薯抗薯瘟病的水杨酸与活性氧的代谢变化

研究不同抗性甘薯品种受薯瘟病菌侵染后水杨酸(SA)和活性氧(ROS)的代谢变化.结果表明,感染薯瘟病菌12 h后甘薯叶片中SA含量增加,增加量与品种抗性呈正相关;接菌后过氧化氢(H2O2)含量增加,过氧化氢酶(CAT)活性下降,抗病品种变化幅度大于感病品种;接菌后抗病品种提高了与产生H2O2相关的酶过氧化物酶(POD)、超氧化物歧化酶(SOD)的活性,而感病品种与此相反,积累H2O2的能力下降,影响系统获得抗性(SAR)的建立.     

Bph36介导的抗性机制及相关信号通路的研究

褐飞虱（Nilaparvata lugens Stål., BPH）是水稻最主要的害虫之一,给水稻生产造成严重的危害。携带不同抗性基因的抗褐飞虱水稻材料抗性机制不同,挖掘普通野生稻抗褐飞虱基因并研究其介导的抗性机制及相关信号通路对水稻育种具有重要的意义。本研究基于课题组前期从广西普通野生稻‘W2183'挖掘出的位于4号染色体InDel标记S13和X48之间38 kb处新基因Bph36,以‘9311'和‘抗蚊青占'为感性对照,05RBPH16和NIL-Bph36为抗性对照,通过褐飞虱宿主选择性、蜜露量测定、褐飞虱存活率及褐飞虱生长速率等方法分析Bph36介导的抗褐飞虱机制;同时,以‘抗蚊青占'为感性对照,NIL-Bph36为抗性对照,通过qRT-PCR分析植物防御昆虫侵害的三大信号途径：水杨酸、茉莉酸和乙烯相关基因表达量的差异。抗性机制研究结果表明：褐飞虱在抗性材料植株上的虫口密度显著低于感性材料植株,抗性材料上的褐飞虱存活率、群体生长率及取食后排泄的蜜露量均比感性对照显著降低。Bph36介导的抗性机制是寄主抗生性和害虫趋避性相互作用的结果。qRT-PCR结果表明：褐飞虱取食后,各个时间段抗性材料NIL-Bph36植株中水杨酸合成相关基因EDS1、PAD4、PAL和水杨酸途径病程相关蛋白基因PR10的表达量显著高于感性材料‘抗蚊青占'植株中的表达量;抗性材料NIL-Bph36植株中,茉莉酸合成基因LOX2和茉莉酸积累基因AOS2的表达量比褐飞虱取食前显著提升,但是比同时段感性材料植株中表达量显著降低;褐飞虱取食后,抗、感性材料植株中乙烯信号途径基因EIN2的表达量都受到抑制,基因ACO3表达量都提高,但2种材料间的差异不显著。茉莉酸途径和乙烯途径参与了NIL-Bph36植株抗褐飞虱的基础防御反应,但Bph36激活的抗性不是茉莉酸和乙烯依赖的信号防御途径而是激活水杨酸依赖的系统获得性抗性。研究结果为进一步研究Bph36与其他抗性基因聚合,培育兼有多种抗性机制和防御信号途径的优良品种奠定基础。     

水杨酸对低温胁迫下枇杷幼果若干生理生化指标的影响

以3年生枇杷容器苗为试验材料,研究在低温胁迫下水杨酸(SA)处理后枇杷幼果若干生理生化指标的变化.结果表明:SA能增强枇杷幼果的抗寒性,其中以70mg/L SA处理枇杷幼果的效果最好;SA处理枇杷幼果,能增强过氧化物酶(POD)、超氧化物歧化酶(SOD)和过氧化氢酶(CAT)活性,提高还原型谷胱甘肽(CSH)和类胡萝卜素(Caro)的含量,降低丙二醛(MDA)含量,抑制叶绿素的降解.