Anti-oxidant activity of oranges after infection with the pathogen Penicillium digitatum or treatment with the biocontrol agent Pantoea agglomerans CPA-2

作者：Torres R^*; Teixido N; Usall J; Abadias M; Mir N; Larrigaudiere C; Vinas I

来源：Biological Control, 2011, 57(2): 103-109.

DOI：10.1016/j.biocontrol.2011.01.006

• Green mold
• Biocontrol agent
• H2O2 production
• Superoxide dismutase
• Catalase
• Postharvest diseases
• Fruit-pathogen interaction

The suppression or generation of hydrogen peroxide (H2O2) in fruit as well as the changes in the superoxide dismutase (SOD) and catalase (CAT) activities due to Penicillium digitatum infection were evaluated on oranges. These biochemical parameters were also determined when oranges were treated with the biocontrol agent Pantoea agglomerans CPA-2. After harvest, oranges were divided in two batches of fruit: one was used immediately and another stored at 4 degrees C for 2 months. In both cases, H2O2 content and changes in enzyme activities were determined at specific time intervals in oranges inoculated with P. digitatum or treated with P. agglomerans. Similar levels of H2O2 were observed during the first 3 days after inoculation in all treatment (control, infected and treated fruit). A short time after, CPA-2 treated fruit showed an accumulation of H2O2 while infected fruit exhibited a sharp decrease in H2O2 levels. An increase of SOD and CAT activities was also observed in CPA-2 treated oranges; in contrast, infected fruit showed a significant reduction of both enzymatic activities. This biochemical approach suggests that P. digitatum suppresses H2O2 production as well as SOD and CAT activities in orange tissue as response to infection process. In contrast, the biocontrol agent P. agglomerans CPA-2 triggers H2O2 production and both enzymatic activities probably as a mechanism of action to prevent citrus fruit against future infections of green mold. Our data suggest that P. agglomerans CPA-2 may act as antagonist against green mold not only by competition for nutrients and space but also by inducing oxidative response in orange tissue.

• 出版日期2011-5