The degree of connection between leaf gas exchange and leaf water potential, and the autonomy of these variables in relation to meteorological conditions were determined in three cultivars of Coffea arabica during clear and cloudy days. High values of vapor pressure deficit, air temperature and photosynthetic photon flux density resulted in low leaf autonomy during a clear day, irrespective the degree of connection among leaf physiological variables. Tight synchronization between physiological and meteorological variables was considered one important cause of net photosynthesis (P N) decreasing during a clear day. In contrast, diurnal P N was around three times higher on a cloudy day, when all cultivars presented high autonomy. Principal component analyses... |