Sarkar Anik, Chakraborty Nilanjan, Acharya Krishnendu
Molecular and Applied Mycology and Plant Pathology Laboratory, Department of Botany, University of Calcutta, Kolkata, 700019, India.
Scottish Church College, Department of Botany, Kolkata, 700006, India.
Plant Physiol Biochem. 2022 Jun 1;180:64-73. doi: 10.1016/j.plaphy.2022.03.038. Epub 2022 Apr 4.
The present study focuses on protection of emerging Alternaria leaf spot disease of chilli by application of chitosan nanoparticles (CNP). CNP was prepared by ionotropic gelation method and characterized. Antifungal potential of CNP was also checked against Alternaria alternata and its mechanisms were unraveled. Foliar application of CNP (0.001%) improved plant innate immunity in two chilli cultivars (one tolerant and one susceptible) by inducing the activities of different defense related enzymes along with total phenol and flavonoid. CNP application also induced callose deposition and reduced cell death in both the cultivar. Signaling molecule nitric oxide (NO) also augmented in CNP treated sets which were confirmed by both biochemical and microscopic data. In order to find out involvement of NO in CNP induced innate immunity in chilli cultivars, both NO surplus and NO depleted conditions were artificially created and defense responses were recorded. It was interesting to note that CNP mediated enhancement of defense responses in chilli plants was compromised in NO depleted condition. These results signify possible involvement of NO in CNP induced defense responses in chilli plants. It is evident from our results that CNP can be used to protect chilli plants against this fungal disease to develop a sustainable management strategy.
本研究聚焦于通过应用壳聚糖纳米颗粒（CNP）来防治辣椒新出现的链格孢叶斑病。通过离子凝胶法制备并表征了CNP。还检测了CNP对链格孢的抗真菌潜力并揭示了其作用机制。对两个辣椒品种（一个抗病品种和一个感病品种）进行叶面喷施0.001%的CNP，通过诱导不同防御相关酶以及总酚和类黄酮的活性，提高了植株的固有免疫力。施用CNP还诱导了胼胝质沉积并减少了两个品种中的细胞死亡。信号分子一氧化氮（NO）在经CNP处理的植株中也增加，这一点得到了生化和微观数据的证实。为了探究NO在CNP诱导辣椒品种固有免疫中的作用，人为创造了NO过剩和NO缺乏的条件并记录防御反应。值得注意的是，在NO缺乏的条件下，CNP介导的辣椒植株防御反应增强受到损害。这些结果表明NO可能参与了CNP诱导的辣椒植株防御反应。从我们的结果可以明显看出，CNP可用于保护辣椒植株免受这种真菌病害，以制定可持续的管理策略。
