诱抗剂处理对甜瓜叶部病害和果实品质的影响

以抗病品种银帝和感病品种卡拉克赛为材料,在露地条件下研究了几种植物提取液和苯并噻二唑(BTH)处理对甜瓜主要叶部病害及果实大小和品质的影响。结果表明,BTH、中草药提取液和侧柏提取液对甜瓜叶部各种主要病害的发生都有明显的抑制效果,尤其对白粉病的抑制效果最好,平均防效达75%。4种诱导剂中,BTH对各种病害的防效都较稳定,平均达51.44%,且在幼果期和伸蔓期+幼果期的预防效果均较植物提取液好。采前诱抗处理能明显提高两品种甜瓜果实品质及抗病品种(银帝)的产量,但对感病品种卡拉克赛产量影响不显著;初花期BTH处理可增加果肉厚度、提高可溶性固形物含量,并能改善果实经济性状。     

BTH处理对不同生育期甜瓜抗白粉病的诱导效应

以幼苗期、伸蔓期和幼果期的黄河蜜甜瓜为试材,研究了苯并噻二唑(BTH)处理对3个生育期甜瓜植株抗白粉病的诱导效应。结果显示:0.25mmol·mL-1BTH对幼苗期和伸蔓期甜瓜植株的诱导效果显著高于幼果期甜瓜植株,而伸蔓期和幼苗期植株之间病情指数差异不显著;0.25mmol·mL-1BTH处理后,幼苗期甜瓜植株叶片中β-1,3-葡聚糖酶(GLU)活性在接种白粉菌后增幅最大,伸蔓期次之,幼果期最小;无论是诱导+接种的植株,还是只接种的植株,叶片中的苯丙氨酸解氨酶(PAL)活性高峰都随着苗龄增大呈现出不断推迟的现象。     

诱抗处理对甜瓜叶片酚类物质代谢的影响

以甜瓜抗白粉病品种‘银帝’和感白粉病品种‘卡拉克赛’为材料,研究诱导抗性处理对其叶片酚类物质代谢的影响及其与抗病性的关系。结果表明：苯丙噻重氮（BTH）和水杨酸（SA）处理以及接种白粉菌均可显著诱导甜瓜叶片苯丙氨酸解氨酶（PAL）、过氧化物酶（POD）、多酚氧化酶（PPO）活性和绿原酸、总酚、类黄酮含量升高,但纳米硅（SiO2）诱导无效。经诱导和接菌后,甜瓜抗病品种叶片PAL、POD、PPO活性和总酚、绿原酸、类黄酮含量高于感病品种。BTH和SA诱导甜瓜抗病性增强的原因之一是提高了叶片次生代谢相关酶的活性,增加了叶组织次生代谢物质的含量。     

BTH处理网纹甜瓜对两种真菌潜伏侵染率的影响

分别于网纹甜瓜开花前7 d、幼果期（花后14 d）、果实迅速膨大期（花后21 d）和网纹形成期（花后28 d）用100 mg·L^-1 BTH对植株进行1、2、3、4次喷洒,分析BTH处理后幼果期、膨大期、网纹形成期和成熟期果实内链格孢（Alternaria alternata）和镰刀菌（Fusarium sp.）潜伏侵染率的变化。结果表明：采前BTH处理可有效控制甜瓜果实内两种真菌的潜伏侵染。1、2、3、4次处理均降低了两种真菌的潜伏侵染率,2、3、4次处理的效果较好,在成熟期总潜伏侵染率均为对照的23.53 %。网纹形成期是两种真菌潜伏侵染的关键时期。采前BTH处理对潜伏于果实内的两种优势病原菌链格孢和镰刀菌的控制效果存在差异,且对果实顶部、中部的控制效果优于底部。     

BTH诱导不同抗性水平甜瓜抗白粉病的效应

诱导植物内在抗性是病害控制的新策略,诱导效应可能与不同品种组成性表达的基础抗性有关。以3个抗性水平不同的品种为材料,研究了苯并噻二唑(BTH)对甜瓜白粉病抗性的诱导效应,以期进一步阐释抗性诱导效应与品种基础抗性的关系。结果显示,BTH诱导甜瓜抗白粉病的效果与品种的基础抗性正相关,对抗病品种的诱导效果高于中抗和感病品种,抗病品种叶片中β-1,3-葡聚糖酶(GLU)和苯丙氨酸解氨酶(PAL)活性增长幅度也较中抗和感病品种大。BTH处理3 d后接种白粉菌,不同抗性水平甜瓜品种叶片中GLU、PAL和多酚氧化酶(PPO)活性均较只接种处理明显上升。叶片超微结构观察显示:乳突结构是寄主对病原菌侵染的一种主动反应,甜瓜抗病品种叶片中乳突结构多呈半圆球型,中抗和感病品种叶片中多呈圆筒型。     

BTH和水杨酸(SA)对甜瓜抗白粉病的诱导作用

研究了BTH和水杨酸(SA)作为诱导剂在不同浓度,不同时期对甜瓜抗白粉病的诱导作用。采用盆栽甜瓜植株,喷施诱导剂,然后接种甜瓜白粉菌的方法测定这2种诱导剂对甜瓜的诱导效果。结果表明2种诱导剂均对甜瓜有明显的诱导作用。BTH最佳诱导浓度为50μg／mL,SA为25μg/mL,平均诱导效果分别为86,6％和83．7％。在最佳诱导浓度下,2种诱导剂诱抗的持效期至少可达17 d。在2—8叶期,BTH和SA处理均有良好的诱导效果,且差异不显著。诱导剂本身对甜瓜白粉病菌分生孢子萌发及菌丝生长无明显影响。     

BTH诱导西瓜甜瓜抗病毒病研究

为了考察S-甲基苯基(1,2,3)噻二唑-7-硫代羧酸酯(benzothiodiazole,BTH)诱导西瓜对小西葫芦黄花叶病毒(Zuccini yellow mosaic virus,ZYMV)、西瓜花叶病毒(Watermelon mosaic virus,WMV)与甜瓜对黄瓜花叶病毒(Cucumber mosaic virus,CMV)的抗病效果,分别在接种ZYMV、WMV、CMV前喷施BTH。结果表明:在接种ZYMV、WMV、CMV前3d用25μg/mLBTH处理西、甜瓜,4周后植株的病情指数减少,相对防效分别为55.6%、56.8%、78.2%;进一步研究发现,经BTH处理后,诱导时间的长短对病情指数有一定的影响;BTH对病毒病的防治效果优于病毒A、病毒K、宁南霉素、芸薹素内酯。     

苯并噻二唑( BTH)诱导黄瓜幼苗对霜霉病抗性的研究

 用0.5 mmol/L BTH (苯并噻二唑) 溶液在接种黄瓜霜霉病菌前4、8、12、24、48、96、168 h (7 d) 和接种后2、4 d处理二叶期的黄瓜幼苗, 结果表明BTH对霜霉病菌无直接的抑制作用, 但能诱导黄瓜幼苗对霜霉病产生局部和系统的抗性, 系统抗性的表达在处理后48 h产生并持续7 d以上。几丁质酶和β-1,3-葡聚糖酶活性测定结果表明, BTH处理可系统性地增强这两种酶的活性, 且与黄瓜对霜霉病的诱导抗性密切相关。     

杧果新品种“桂热杧3号”对炭疽病和细菌性黑斑病的抗性评价初报

炭疽病和细菌性黑斑病是杧果生产上的重要病害,严重影响杧果的产量和质量。采用室内离体接种鉴定法,以抗病品种台农1号杧为对照,对桂热杧3号果实不同发育时期(幼果期、膨大期、成熟期)及转绿期叶片进行炭疽病和细菌性黑斑病的抗病性测定。结果表明,幼果期、果实膨大期、果实成熟期和叶片转绿期的炭疽病病情指数分别为37.78、25.33、31.33、28.00,抗性评价为抗病。幼果期、果实膨大期、果实成熟期、叶片转绿期的细菌性黑斑病的病情指数分别为30.56、22.92、27.38、19.45,幼果期抗病评价为中抗,其余3个时期为抗病。桂热杧3号幼果期和果实膨大期的炭疽病病情指数达显著性差异水平(p0.05),桂热3号杧与台农1号杧转绿期叶片炭疽病病情指数达显著性差异水平。说明桂热杧3号是一个对炭疽病抗病、对细菌性黑斑病中抗的晚熟杧果品种。     

5%氟唑活化酯乳油对西瓜甜瓜白粉病的诱导抗病效果评价

【目的】通过田间药效试验评价新型诱导抗病激活剂5%氟唑活化酯EC对西瓜甜瓜白粉病的诱导抗病效果,为合理使用5%氟唑活化酯EC提供依据。【方法】采用叶面喷雾法对西瓜甜瓜进行诱导施药,分别于2016年及2017年在北京顺义杨镇、北京延庆县康庄镇小丰营村及北京市海淀区中国农业科学院蔬菜花卉研究所所区农场3地7个点进行田间西瓜甜瓜白粉病的诱导抗病试验。【结果】综合2 a(年)多的试验发现,5%氟唑活化酯EC对西瓜甜瓜白粉病的诱导抗病效果随质量分数增大有增高趋势,随施药次数增多有增高趋势。对于甜瓜白粉病,100、50和25 mg·kg~(-1)的5%氟唑活化酯EC诱抗效果显著高于杀菌剂40%氟硅唑EC;对于西瓜白粉病,100、50 mg·kg~(-1)的5%氟唑活化酯EC诱抗效果显著高于杀菌剂40%氟硅唑EC。但100、50 mg·kg~(-1)质量分数下有药害问题,产量也会受到影响。5%氟唑活化酯EC在质量分数为10 mg·kg~(-1)、诱导5次、诱导间隔期7 d条件下,对西瓜白粉病的诱导抗病效果最好,为97.5%,与对照诱导抗病激活剂苯并噻二唑(BTH)及杀菌剂42.8%氟菌·肟菌酯悬浮剂无显著差异。5%氟唑活化酯EC在质量分数10 mg·kg~(-1)、诱导5次、诱导间隔期7 d条件下,对甜瓜白粉病的诱导抗病效果最好,为63.89%。5%氟唑活化酯EC在质量分数10 mg·kg~(-1)、诱导5次、诱导间隔期7 d条件下,对西瓜白粉病的诱导抗病效果最好,为69.16%。【结论】5%氟唑活化酯EC对西瓜甜瓜白粉病有较好的诱导抗病效果,其最佳诱导质量分数为10~25 mg·kg~(-1),最佳诱导次数为5次,可以取代杀菌剂施用,效果与BTH等同。     

BTH处理对甜瓜苗期抗蔓枯病相关POD和PPO酶活性的影响

研究了BTH处理和蔓枯病病原菌接种对甜瓜抗蔓枯病相关的POD和PPO的影响,结果表明,BTH处理能有效提高不同甜瓜品种对蔓枯病的抗性.BTH处理第1、2和4天,抗蔓枯病品系‘PI420145’和蔓枯病感病品种‘伊丽莎白’的第3叶和第5叶的POD和PPO酶活性均高于对照;BTH和蔓枯病病原共同处理第1、3、5、7天,‘PI420145’和‘伊丽莎白’的第3叶和第5叶的POD和PPO酶活性高于蔓枯病病原菌处理;所有的处理中‘PI420145’的POD和PPO的酶活性均高于‘伊丽莎白’.表明POD和PPO酶活性与甜瓜对蔓枯病的抗性呈正相关.     

BTH诱导甜瓜愈伤组织活性氧代谢和抗性酶活性的信号途径

通过对含有苯并噻二唑(BTH)、咖啡酸(CA)或氯化钴(CC)等不同MS培养上甜瓜愈伤组织的研究,测定了超氧阴离子(O2■)产生速率、过氧化氢(H2O2)含量及抗性相关酶活性的变化,探讨了BTH诱导的甜瓜ROS代谢和抗性酶活性及其相关的信号途径。结果表明,CA可以消除BTH对甜瓜愈伤组织O2■增加和H2O2积累的诱导作用;CA或CC能够部分抵消BTH对SOD增强的诱导作用;CC对BTH诱导的POD增强具有抑制效应,CA+CC可完全消除BTH对POD的诱导作用;CA和CC均能促进BTH对PAL增强的诱导作用,且具有协同效应。BTH对甜瓜O2■升高、H2O2积累和CAT降低的诱导主要通过SA途径实现,对POD的影响主要通过ET途径实现,对SOD升高的诱导通过SA和ET 2条途径实现,而对PAL活性的影响通过ET和SA以外的途径实现。     

Pre-harvest application of 2, 6-dichloroisonicotinic acid, -aminobutyric acid or benzothiadiazole to control post-harvest storage diseases of melons by inducing systemic acquired resistance (SAR)

Summary

Field-grown rockmelon plants were treated with -aminobutyric acid (BABA), 2,6-dichloroisonicotinic acid (INA), benzothiadiazole (BTH) or water during fruit development and evaluated for increased resistance against plant diseases or post-harvest pathogens. One experiment was conducted at Camden, NSW, Australia (INA, BABA or water). Two experiments were at Griffith, NSW, Australia (INA, BTH or water). Growing plants and harvested fruits were assessed for disease symptoms from natural infections and assayed for the accumulation of chitinase and peroxidase, two major pathogenesis-related (PR) proteins induced as a result of systemic acquired resistance (SAR). Harvested fruit from both BTH- or INA-treated plants showed a significant (P < 0.05) reduction in the severity and incidence of post-harvest storage diseases mainly caused by Fusarium, Alternaria and Rhizopus. However, there were no differences in disease severity and the incidence of rots between using four fortnightly foliar sprays of INA or BTH during flowering and fruit development, or a single spray of BTH, 2 weeks before harvest. Each approach showed an equivalent reduction in storage diseases. Plants treated with BABA showed less resistance against powdery mildew in the field and storage rots from natural inoculum, and lower increases in chitinase and peroxidase activities than those treated with INA. In all trials, an additional post-harvest dip with guazatine [0.05% (w/v)] gave a substantial reduction in melon storage rots. Pre-harvest application of INA or BTH reduced the occurrence of powdery mildew and downy mildew on the leaves. Over the three field-experiments, INA had a small phytotoxic effect causing lesion-like symptoms on leaves and affected plant growth, but not yield, at Camden, when applied during flowering and 2 weeks after flowering. However, INA did not produce any phytotoxic effects in the two experiments at Griffith when applied serially, four times to plants after flowering.     

苯并噻二唑(BTH)对苹果抗斑点落叶病的诱导

对诱导剂苯并噻二唑(Benzothiadiazole,BTH)在不同质量浓度下对苹果抗斑点落叶病的诱导作用,以及诱导抗性与木质素和富含羟脯氨酸糖蛋白(HRGP)含量的关系进行了研究。BTH诱导苹果主枝顶梢,整株接菌后,采用病情指数统计发病程度。培养基测定抑菌活性;比色法测定苹果受诱导后木质素和HRGP含量。结果表明,BTH能诱导苹果产生系统获得性抗性,当诱导质量浓度为150mg/L时,可使病情指数由对照的26.34下降到16.87,抗病持效期可达15d,而BTH本身对苹果斑点落叶病菌分生孢子萌发及菌丝生长无明显影响。生理指标测定表明,木质素和富含羟脯氨酸糖蛋白(HRGP)含量增加,可能是抗病性增强的生理原因。     

Benzothiadiazole- or methyl jasmonate-induced resistance to Colletotrichum musae in harvested banana fruit is related to elevated defense enzyme activities

Summary

The ability of benzothiadiazole (BTH) or methyl jasmonate (MeJA) to induce disease resistance in harvested banana fruits was investigated in relation to the activities of several defense-related enzymes. Harvested banana fruit were sprayed with BTH or MeJA solution before being stored at 22°C. Disease development and the activities of six defense-related enzymes were monitored during storage. Compared with untreated fruits, BTH or MeJA treatment significantly reduced the severity of disease in non-inoculated bananas, and lesion diameters and the incidence of disease in bananas inoculated with Colletotrichum musae. The activities of the defense-related enzymes peroxidase (POD), catalase (CAT), polyphenol oxidase (PPO), phenylalanine ammonia lyase (PAL), β1,3-glucanase, and chitinase were all enhanced in BTH- and in MeJA-treated banana fruit whether inoculated with the pathogen or not. The results suggest that post-harvest decay in bananas can be controlled by BTH or MeJA, and involves activation of the disease defense system. In non-inoculated bananas, MeJA and BTH had similar effects on the three defense enzymes (CAT, PPO and PAL), but different effects on the three PR proteins (POD, β1,3-glucanase and chitinase). In inoculated bananas, MeJA and BTH had similar effects on all six enzymes.