ISHS Acta Horticulturae 681: IV International Congress on Artichoke
APPRAISAL OF OXIDATIVE ENZYMATIC ACTIVITIES AND INULIN CONTENT DURING ARTICHOKE GROWTH |
| Authors: | L. Almela, J.A. Muñoz, M.J. Roca, J.A. Fernández-López |
| Keywords: | Fertigation, Cynara scolymus, PPO, POD, fructans, chilling stress. |
| Abstract:
The evolution of polyphenol oxidase (PPO) and peroxidase (POD), two enzymatic activities related to artichoke quality, and inulin, the main polysaccharide accumulated by this plant, were studied during plant growth, and in response to chilling stress. The experiment was carried out using the artichoke of the "Blanca de Tudela" variety. Irrigation and fertilization were performed by fertigation with 1-0,5-1,5 N/P/K ratio. Soil was of sandy clay loam texture, a type of soil well suited to artichoke cultivation. The results of the chemical-physical analysis of water and soil did not reveal any limiting factor for the cultivation of the artichoke, that is slightly tolerant to salinity and well adapted to soils with a high calcium carbonate content. PPO activity hardly changed during the sampling period. Only cold wounding was capable of increasing the expression of PPO activity. In May, the high temperatures induced lignification, a mechanism that occurs through the activation of PPO activity in the heads, in a similar way to that which occurs in any fruit. POD activity was lower in hearts than in the external bracts, a finding that is interpreted as a result of the high level of lignification in the external bracts and as response to the stress caused because of a drop in temperature. In the coldest periods inulin was accumulated; a mechanism that may help with osmotic adjustment. When warmer temperatures arrived, the reserve of carbohydrate decreased, a situation that was particularly evident in the external bracts. | |
Download Adobe Acrobat Reader (free software to read PDF files) | |
