CHANGES IN SH-CONTAINING COMPOUNDS AND CATALASE ACTIVITY IN APRICOT FLOWER BUD DURING THE WINTER SEASON

Accumulation and variations of sulfhydryl compounds (SH), reduced glut athione (GSH) and catalase activity during the flower bud development cycle and their relationship were studied in two apricot cultivars, 'S . Castrese' and 'Portici', which differ in production behaviour in dif ferent years and environments. The changes in catalase activity, SH an d GSH showed three distinct phases from November to February. In the f irst two phases, a gradual increase in catalase activity and reduced g lutathione content was observed, paralleled by a decrease in total SH concentration. During phase 3 (early February), at the same time with an increase in total SH and GSH, catalase activity showed a tendency t o decrease. The two cultivars showed a difference in flower bud respon se, which was detected as early as the first observations in autumn. I n particular, 'S. Castrese' was found to present constant and elevated catalase activity and a greater GSH content. (C) 1998 Elsevier Scienc e B.V.