Beta-Aminobutyric acid-mediated enhancement of resistance in tobacco against TMV and consideration of its capability in wounded tobacco plants.
الكلمات الدالة
نبذة مختصرة
Systemic acquired resistance (SAR) is an important component of disease-resistance arsenal of plants, and is associated with enhanced potency of activating local and systemic defense-related responses upon pathogen attack. In this report, we demonstrated that pre-treatment with beta-aminobutyric acid (BABA), a new elicitor of SAR in the plants, enhanced resistance against tobacco mosaic virus (TMV) in a temperately-sensitive tobacco (Nicotiana tabacum L.) cultivar Yunyan 85. The resistance is based on the elicitation of defense-related responses induced by BABA that brings the TMV-susceptible tobacco plants to a defense-ready state, even before exposure to the pathogen. The induced resistance was strongly associated with potentiated activation of defense-related enzymes [phenylalanine ammonia lyase (PAL) and polyphenol oxidase (PPO)] activities, proportional to the concentration of the BABA sprayed. Interestingly, simultaneous clipping, an important agricultural practice in tobacco production, attenuated BABA-mediated enhancement of TMV resistance in tobacco. The changes in the defense-related enzymes activities indicated that the interaction between BABA and wounding was reciprocally antagonistic. Moreover, such a negative interaction regulated the expression of defense-related enzymes. depending on the time of induction.