Swarupa V, Ravishankar K V, Rekha A
Division of Biotechnology, Indian Institute of Horticultural Research, Hesaraghatta Lake Post, Bengaluru, 560089, India.
Planta. 2014 Apr;239(4):735-51. doi: 10.1007/s00425-013-2024-8. Epub 2014 Jan 14.
Soil-borne fungal pathogen, Fusarium oxysporum causes major economic losses by inducing necrosis and wilting symptoms in many crop plants. Management of fusarium wilt is achieved mainly by the use of chemical fungicides which affect the soil health and their efficiency is often limited by pathogenic variability. Hence understanding the nature of interaction between pathogen and host may help to select and improve better cultivars. Current research evidences highlight the role of oxidative burst and antioxidant enzymes indicating that ROS act as an important signaling molecule in banana defense response against Fusarium oxysporum f.sp. cubense. The role of jasmonic acid signaling in plant defense against necrotrophic pathogens is well recognized. But recent studies show that the role of salicylic acid is complex and ambiguous against necrotrophic pathogens like Fusarium oxysporum, leading to many intriguing questions about its relationship between other signaling compounds. In case of banana, a major challenge is to identify specific receptors for effector proteins like SIX proteins and also the components of various signal transduction pathways. Significant progress has been made to uncover the role of defense genes but is limited to only model plants such as Arabidopsis and tomato. Keeping this in view, we review the host response, pathogen diversity, current understanding of biochemical and molecular changes that occur during host and pathogen interaction. Developing resistant cultivars through mutation, breeding, transgenic and cisgenic approaches have been discussed. This would help us to understand host defenses against Fusarium oxysporum and to formulate strategies to develop tolerant cultivars.
土壤传播的真菌病原体尖孢镰刀菌通过在许多农作物中引发坏死和枯萎症状，造成重大经济损失。镰刀菌枯萎病的防治主要通过使用化学杀菌剂来实现，这会影响土壤健康，而且其效果往往受到病原体变异性的限制。因此，了解病原体与宿主之间相互作用的本质，可能有助于选择和培育出更好的品种。目前的研究证据突出了氧化爆发和抗氧化酶的作用，表明活性氧在香蕉对尖孢镰刀菌古巴专化型的防御反应中作为重要的信号分子发挥作用。茉莉酸信号在植物对坏死性病原菌的防御中的作用已得到充分认识。但最近的研究表明，水杨酸对尖孢镰刀菌等坏死性病原菌的作用复杂且不明确，这引发了许多关于其与其他信号化合物之间关系的有趣问题。就香蕉而言，一个主要挑战是确定效应蛋白（如SIX蛋白）的特定受体以及各种信号转导途径的组成部分。在揭示防御基因的作用方面已取得重大进展，但仅限于拟南芥和番茄等模式植物。鉴于此，我们综述了宿主反应、病原体多样性，以及目前对宿主与病原体相互作用过程中发生的生化和分子变化的理解。还讨论了通过突变、育种、转基因和顺基因方法培育抗性品种。这将有助于我们了解宿主对尖孢镰刀菌的防御机制，并制定培育耐性品种的策略。
