Active oxygen detoxifying enzymes and phenylalanine ammonia-lyase in the ethylene-induced chilling tolerance in citrus fruit.
The effects of applying ethylene (2 microL x L(-)(1)) during cold storage of Fortune mandarins on the development of chilling-induced peel damage and on changes in the activities of the enzymes of the antioxidant system, superoxide dismutase, catalase (CAT), ascorbate peroxidase, guaiacol peroxidase, and glutathione reductase, and on phenylalanine ammonia-lyase (PAL) have been investigated. Chilling damage was reduced by applying ethylene during fruit storage at 1.5 degrees C. PAL activity increased in response to cold stress and was higher in fruit held under ethylene than under air during the whole storage period, whereas CAT was temporarily higher in ethylene-treated fruit. In contrast, the activities of the other enzymes were not increased by ethylene. The global results suggest that the ethylene-induced chilling tolerance in Fortune mandarins might be due to increased PAL and CAT activities.
Lafuente
María T
MT
Instituto de Agroquímica y Tecnología de Alimentos (IATA-CSIC), Apartado de Correos 73, 46100 Burjassot, Valencia, Spain. postco@iata.csic.es
Sala
José M
JM
Zacarias
Lorenzo
L
D060387:Ascorbate Peroxidases; D002374:Catalase / Q000378:metabolism*; D002957:Citrus / Q000201:enzymology*; D003080:Cold Temperature; D005030:Ethylenes / Q000494:pharmacology*; D005638:Fruit / Q000201:enzymology*; D005980:Glutathione Reductase / Q000378:metabolism; D010544:Peroxidases / Q000378:metabolism; D010650:Phenylalanine Ammonia-Lyase / Q000378:metabolism*; D013482:Superoxide Dismutase / Q000378:metabolism
D005030:Ethylenes; C036216:ethylene; D010544:Peroxidases; D060387:Ascorbate Peroxidases; D002374:Catalase; D013482:Superoxide Dismutase; D005980:Glutathione Reductase; D010650:Phenylalanine Ammonia-Lyase