Phytopathogens induced pathogenesis-related (PR) proteins as well as defense-related signaling moleculesare imperative part of an innate immune system in plant especially for systemic acquired resistance. The present study was undertaken to find out the role of chemical elicitors on expression of pathogenicity related genes in susceptible and resistant cultivars of tomato (Solanum lycopersicum L) against bacterial wilt and alsoon reduction of disease incidence. Two chemical elicitors i. e. Salicylic acid (SA) and β-amino butyric acid (BABA) were used in vitro, at 50, 100 and 150 μM concentrations to observe their effect on the growth of Ralstonia solanacearum (Smith) (Yabuuchi et al.1995). The growth of R. solanacearum was significantly inhibited by BABA and SA at 50 μM under in vitro conditions significantly. Furthermore, the relative differential expression of PR gene (PR1a, PR1b, PR2, and PR5 genes) transcripts were analyzed in both resistant (cv. Hawaii 7996) and susceptible (cv. Pusa Ruby) tomato cultivars when inoculated with R. solanacearum UTT-25 (RS)eitheralone or in combination with 50 μM concentration of BABA and SA separately at 6, 24, 48 & 96 hpi using RT-PCR. The maximum 5.61 fold up-regulation of PR1a gene was observed with SA (50 μM) + RS while 6.44 fold upregulation of PR1b gene was noticed with SA (50 μM) alone at 48hpi in cv. Pusa Ruby. Whereas, resistant nature of cv. Hawaii7996 does not allow R. solanacearum UTT-25 to multiply, so it does not show any upregulation except with R. solanacearum alone at 96hpi of the treatment. The histochemical detection has also confirmed the minimal production of defence-related reactive oxygen species (ROS) in stems and leaves of cv. Pusa Ruby than cv. Hawaii7996 in the presence of chemical elicitors. The wilt incidences on both the cultivars at varied concentrations of the elicitors used were decreased or delayed as compared to control. In cv. Pusa Ruby with Beta-butyric acid (50 μm) + R. solanacearum, minimum wilt incidence of 9.34 % were noticed on 16th day. However, in Hawaii7996 only 6.79 % wilt incidences were observed with Salicylic acid (50 μm) + R. solanacearumon 24th day as compared to control. Thus, our findings suggest that chemical elicitors SA (50 μM) had inducedresistance in susceptible cultivar to reduce wilt incidence significantly under glasshouse conditions.

植物病原体诱导的发病机制相关 (PR) 蛋白以及防御相关信号分子是植物先天免疫系统的必要组成部分，尤其是对于系统获得性抗性。本研究旨在找出化学诱导剂在抗青枯病的番茄 ( Solanum lycopersicum L)易感和抗性品种中致病相关基因表达以及降低发病率的作用。在体外使用了两种化学诱导剂，即水杨酸 (SA) 和 β-氨基丁酸 (BABA) ，浓度分别为 50、100 和 150 μM，以观察它们对青枯病菌 (Smith)生长的影响（Yabuuchi 等人，1995 年））。的成长在体外条件下，50 μM 的 BABA 和 SA 显着抑制青枯菌。此外，当接种青枯病菌 UTT-时，在抗性（栽培品种夏威夷 7996）和易感性（栽培品种 Pusa Ruby）番茄栽培品种中分析了 PR 基因（PR1a、PR1b、PR2 和 PR5 基因）转录物的相对差异表达。25 (RS) 单独或与 50 μM 浓度的 BABA 和 SA 组合，分别在 6、24、48 和 96 hpi 使用 RT-PCR。用 SA（50 μM）+ RS观察到 PR1a 基因的最大 5.61 倍上调，而在 cv.48hpi 时，单独用 SA（50 μM）观察到 PR1b 基因的 6.44 倍上调。普萨红宝石。然而，cv的抗性。Hawaii7996 不允许青枯菌UTT-25 繁殖，因此它没有显示任何上调，除了在治疗的 96hpi 单独使用青枯菌。组织化学检测还证实了 cv. 茎和叶中防御相关活性氧 (ROS) 的产生最少。Pusa Ruby 比 cv。Hawaii7996 在化学诱导剂的存在下。与对照相比，使用不同浓度的诱导剂的两个栽培品种的枯萎发生率均降低或延迟。在简历中。Pusa Ruby 与 β-丁酸 (50 μm) +  R. solanacearum 一起，在第 16 天发现最低枯萎发生率为 9.34 %。然而，在夏威夷 7996 中，水杨酸 (50 μm) +青枯菌仅观察到 6.79% 的枯萎发生率 与对照组相比，第 24 天。因此，我们的研究结果表明，化学诱导剂 SA（50 μM）在易感品种中具有诱导抗性，可显着降低温室条件下的枯萎发生率。