In order to determine the possible association between the
flavonoids investigated, Pearson’s correlation coefficients were
generated according to the sampling times. All correlations were
either positive or not significant (Table 3). Total flavonoid concentration
was significantly correlated with quercetin, kaempferol and
isoquercitrin in C. paliurus leaves for all the sampling times
(P < 0.05). The concentrations of quercetin and kaempferol, which
are produced through the same biosynthesis pathway in plants,
were also significantly correlated at all the five sampling times,
whereas the levels of quercetin and isoquercitrin in C. paliurus
leaves were not significantly correlated, except for August. Interestingly,
the correlation between kaempferol and isoquercitrin
was significant for the samples collected in August and October
(P < 0.01), while positive but not significant correlation was observed
in June, July and September.