Values of maximum quantum efficiency of PSII (Fv/Fm) were always lower at midday than at dawn, resulting mainly from the fact that values of Fm were lower at midday than at dawn (t-test, p < 0.0001; data not presented).
Values of maximum quantum efficiency of PSII (Fv/Fm) were alwayslower at midday than at dawn, resulting mainly from the factthat values of Fm were lower at midday than at dawn (t-test,p < 0.0001; data not presented).