Siciliano Ilenia, Amaral Carneiro Greice, Spadaro Davide, Garibaldi Angelo, Gullino Maria Lodovica
Centre of Competence for the Innovation in the Agro-Environmental Sector (AGROINNOVA) and ‡Department of Agricultural, Forestry and Food Sciences (DISAFA), University of Torino , Largo P. Braccini 2, 10095 Grugliasco, Turin, Italy.
J Agric Food Chem. 2015 Sep 23;63(37):8134-42. doi: 10.1021/acs.jafc.5b03018. Epub 2015 Sep 15.
Fusarium fujikuroi, the causal agent of bakanae disease, is the main seedborne pathogen on rice. To understand the basis of rice resistance, a quantitative method to simultaneously detect phytohormones and phytoalexins was developed by using HPLC-MS/MS. With this method dynamic profiles and possible interactions of defense-related phytohormones and phytoalexins were investigated on two rice cultivars, inoculated or not with F. fujikuroi. In the resistant cultivar Selenio, the presence of pathogen induced high production of phytoalexins, mainly sakuranetin, and symptoms of bakanae were not observed. On the contrary, in the susceptible genotype Dorella, the pathogen induced the production of gibberellin and abscisic acid and inhibited jasmonic acid production, phytoalexins were very low, and bakanae symptoms were observed. The results suggested that a wide range of secondary metabolites are involved in plant defense against pathogens and phytoalexin synthesis could be an important factor for rice resistance against bakanae disease.
藤仓镰孢菌是水稻恶苗病的病原菌，是水稻上主要的种传病原体。为了解水稻抗性的基础，利用高效液相色谱-串联质谱法（HPLC-MS/MS）开发了一种同时检测植物激素和植保素的定量方法。采用该方法，研究了两个接种或未接种藤仓镰孢菌的水稻品种中与防御相关的植物激素和植保素的动态变化及可能的相互作用。在抗病品种Selenio中，病原菌的存在诱导了植保素的大量产生，主要是樱花素，且未观察到恶苗病症状。相反，在感病基因型Dorella中，病原菌诱导了赤霉素和脱落酸的产生，抑制了茉莉酸的产生，植保素含量很低，并观察到恶苗病症状。结果表明，多种次生代谢产物参与了植物对病原体的防御，植保素合成可能是水稻对恶苗病抗性的一个重要因素。
