Role of hydrogen peroxide in the development of postharvest disease in oranges caused by Penicillium digitatum
R. Torres, N. Mir, N. Teixidó, J. Usall, M. Abadias, C. Larrigaudiere and I. Viñas.
Journal of Plant Pathology Volume 90 (2, Supplement) August 2008, Book of Abstract, 9th International Congress of Plant Pathology, August 24-29, 2008 Torino,Italy,. 507 pages.
2008
บทคัดย่อ
Role of hydrogen peroxide in the development of postharvest disease in oranges caused by Penicillium digitatum
Plant cell strategies against pathogens include mechanisms directed at weakening or killing the pathogen. These include the accumulation of reactive oxygen species (ROSs) such as H2O2and the superoxide anion, in a process known as the oxidative burst. The ROSs generated during these reactions have direct antimicrobial activity that inhibits fungal spore germination, and could be involved in other processes such as induction of systemic responses. Our objective was to understand the role ofH2O2in the response of oranges infected withPenicillium digitatumor treated with the biocontrol agentPantoea agglomeransCPA-2. The participation of antioxidant enzymes such as superoxide dismutase and catalase, and the peroxidases was also investigated.H2O2levels and enzymatic activities were evaluated inValenciaoranges, after infection with the pathogen or treatment with the antagonist. We used fruit just at harvest and after postharvest storage. Similar levels ofH2O2were observed after 72 h in all fruits. However, a decrease was observed in fruits with visible symptoms of decay, and high levels ofH2O2were found in fruits without the pathogen. Changes in enzyme activities were also observed due to the presence ofP. digitatumorP. agglomerans. The different behaviour observed in oranges in the presence of pathogen or antagonist might be explained in terms of a suppression or induction of hydrogen peroxide metabolism.