The mean PPO activity in 22 researched
scab-resistant apple cultivars
varied between 5-240 U/g f.w.
Almost 40% of investigated cultivars
from two harvest seasons were characterized
by repeatability of PPO
activity, with a standard deviation
below 30%. Almost half of the 22
cultivars were characterized by PPO
activity below 50 U/g f.w. On the
other hand, almost 15% of the cultivars,
i.e.: ‘Angold’, ‘Selena’ and
‘Gold Milenium’ showed the hightest
PPO activity between 140-
250 U/g f.w. Polyphenol content in
researched apple cultivars varied
160-900 mg/kg f.w. Statistical analysis
indicated that the correlation between
PPO activity and sum of polyphenols
and polyphenol groups in the researched cultivars does not prove
the interdependence between those
values. For the investigated cultivars
a satisfactory correlation between
PPO activity and tyrosine content
was not confirmed