Abstract
Ethylene production and activities of three cell wall degrading enzymes [polygalacturonase (PG), α-L-arabinofuranosidase (AF-ase) and β-D-galactosidase (GA-ase)] during rapid softening of Japanese persimmon 'Saijo' fruit were investigated. Ethylene production and activities of PG and GA-ase in fruit picked at the late mature stage were 1/100, 1/10 and 1/2 of young immature fruit, respectively. The late mature fruit softened somewhat slower than young fruit. Activity of AF-ase both in green immature and fully mature fruit during rapid softening increased twice as much as the fruit at harvest, indicating that the enzyme plays an important role in the softening process. That AF-ase was already active in firm fruit at harvest suggest that another, more direct factor, might also be associated with the softening. These results suggest that the degradation of non-cellulosic neutral polysaccharide by AF-ase is at least related to the rapid softening of Japanese persimmon 'Saijo' fruit.
