Fig. 6
From: Photosynthetic characteristics of cotton are enhanced by altering the timing of mulch film removal
Coefficient of photochemical fluorescence quenching assuming an interconnected PS-II antennae (qL) and Stern-Volmer type non-photochemical fluorescence quenching (NPQ) of cotton varieties (XLZ42 and XLZ45), at different days since flowering in various treatment groups: 1 and 10 days before the first irrigation (T1, T10, respectively) and 1 day before the second irrigation (E1) after seedling emergence, during 2016–2017. The control group (CK) had film mulching throughout the growth stages. Bars are means ± standard deviation (n = 3)