Abstract:
In Tunisia, Orobanche foetida Poir. is considered an important agricultural biotic constraint on faba bean (Vicia faba L.) production. An innovative control method for managing this weed in faba bean is induced resistance through inoculation by rhizobia strains. In this study, we explored the biochemical dynamics in V. faba L. minor inoculated by rhizobia in response to O. foetida parasitism. A systemic induced resistant reaction was evaluated through an assay of peroxidase (POX), polyphenol oxidase (PPO) and phenyl alanine ammonialyase (PAL) activity and phenolic compound and hydrogen peroxide (H2O2) accumulation in faba bean plants infested with O. foetida and inoculated with rhizobia. Two rhizobia strains (Mat, Bj1) and a susceptible variety of cultivar Badi were used in a co-culture Petri dish experiment. We found that Mat inoculation significantly decreased O. foetida germination and the number of tubercles on the faba bean roots by 87% and 88%, respectively. Following Bj1 inoculation, significant decreases were only observed in O. foetida germination (62%). In addition, Mat and Bj1 inoculation induced a delay in tubercle formation (two weeks) and necrosis in the attached tubercles (12.50% and 4.16%, respectively) compared to the infested control. The resistance of V. faba to O. foetida following Mat strain inoculation was mainly associated with a relatively more efficient enzymatic antioxidative response. The antioxidant enzyme activity was enhanced following Mat inoculation of the infected faba bean plant. Indeed, increases of 45%, 67% and 86% were recorded in the POX, PPO and PAL activity, respectively. Improvements of 56% and 12% were also observed in the soluble phenolic and H2O2 contents. Regarding inoculation with the Bj1 strain, significant increases were only observed in soluble phenolic and H2O2 contents and PPO activity (especially at 45 days after inoculation) compared to the infested control. These results imply that inoculation with the rhizobia strains (especially Mat) induced resistance and could bio-protect V. faba against O. foetida parasitism by inducing systemic resistance, although complete protectionwas not achieved by rhizobia inoculation. The Mat strain could be used as a potential candidate for the development of an integrated method for controlling O. foetida parasitism in faba bean.
摘要:
在突尼斯,OrobanchefoetidaPoir.被认为是蚕豆(ViciafabaL.)生产的重要农业生物约束。一种用于管理蚕豆中这种杂草的创新控制方法是通过根瘤菌菌株接种诱导抗性。在这项研究中,我们探索了根瘤菌接种的V.fabaL.minor对O.foetida寄生的反应的生化动力学。通过过氧化物酶(POX)的测定来评估系统诱导的抗性反应,在用O.foetida侵染并接种根瘤菌的蚕豆植物中,多酚氧化酶(PPO)和苯丙氨酸解氨酶(PAL)活性以及酚类化合物和过氧化氢(H2O2)的积累。两种根瘤菌菌株(Mat,Bj1)和易感品种Badi用于共培养培养皿实验。我们发现,Mat接种显着降低了蚕豆根上的O.foetida发芽和结节数量分别为87%和88%,分别。接种Bj1后,仅在O.foetida发芽中观察到显着减少(62%)。此外,Mat和Bj1接种导致结节形成延迟(两周)和附着结节坏死(12.50%和4.16%,分别)与受感染的对照相比。Mat菌株接种后,蚕豆对O.foetida的抗性主要与相对更有效的酶促抗氧化反应有关。Mat接种受感染的蚕豆植物后,抗氧化酶活性得到增强。的确,增长45%,67%和86%记录在POX中,PPO和PAL活性,分别。还观察到可溶性酚和H2O2含量分别提高了56%和12%。关于接种Bj1菌株,与受感染的对照相比,仅观察到可溶性酚和H2O2含量以及PPO活性的显着增加(尤其是在接种后45天)。这些结果表明,接种根瘤菌菌株(尤其是Mat)可以诱导抗性,并可以通过诱导系统抗性来生物保护蚕豆免受O.foetida寄生,尽管根瘤菌接种不能实现完全保护。Mat菌株可用作开发控制蚕豆中O.foetida寄生的综合方法的潜在候选者。