Inhibition of photosynthesis in olive trees (Olea europaeaL.) during water stress and rewatering

Abstract

The effect of high levels of natural light on leaf photosynthesis in olive trees {Olea europaea L. van Coratina), grown in pots outdoors in the summer and subjected to water, stress, was studied. Net photosynthetic rates reached maximum values early in the morning in both control and stressed plants and subsequently declined gradually. This inactivation of photosynthetic activity was accompanied by changes in the fluorescence characteristics of the upper intact leaf surface. The maximum fluorescence yield {Fp) and the ratio Fv/Fp decreased at midday especially in water-stressed plants, but the initial fluorescence {Fo) rose to a maximum value at midday and declined again in the afternoon. In control plants the values of maximum fluorescence Fp and the ratio Fv/Fp increased again in the afternoon and had recovered almost completely by 8 p.m. as the leaf water potential recovered. In stressed plants this diurnal recovery was not complete, so that the photosynthetic rates and the ratio Fv/Fp declined gradually during the development of water stress. These results indicate that in olive trees subjected to severe water stress the non-stomatal component of photosynthesis was affected and perhaps a light-dependent inactivation of the primary photochemistry associated with photosystem II (PSII) occurred. Four to five days after rewatering severely stressed plants, the predawn leaf water potential, net photosynthetic rates and chlorophyll fluorescence indices recovered only partially.

Preliminary Evaluation of 29 Olive (Olea europaea L.) Cultivars for Production and Alternate Bearing, in the Huasco Valley, Northern Chile

“…Olive cultivation, however, has extended beyond this region to South America, South Africa and Australia. The olive is considered a dry climate crop, capable of sustaining long periods of water deficit (Angelopoulos et al, 1996;Selles et al, 2006) and with a moderate tolerance to saline soils (Benlloch et al, 1991;Isidoro and Aragüés, 2006), because of which it has been successfully cultivated in saline soils where other fruit trees cannot grow.…”

Extrapolating base-line trunk shrinkage reference equations across olive orchards

“…3 and 4). These (Angelopoulos et al, 1996). Such differences in the daily pattern 375 stomata could suggest different respond to high transpiration conditions.…”

Fluorescência da clorofila a em folhas de tangerineira 'Ponkan' e limeira ácida 'Tahiti' submetidas ao estresse hídrico

“…Além disso, podem ocorrer limitações em componentes não estomáticos, com danos nos centros de reação do fotossistema FLUoRESCêNCIA DA CLoRoFILA a EM FoLhAS DE TANGERINEIRA 'PoNKAN'... II, os quais podem apresentar reversão parcial após reidratação (Angelopoulos et al, 1996).…”

“…As restrições estomáticas no suprimento de Co 2 , pela falta de água, podem provocar limitações em componentes não estomáticos, com danos nos centros de reação do fotossistema II. Angelopoulos et al (1996) (Bulkhov et al, 1999).…”