Midday depression of photosynthesis has important consequences for ecosystem carbon exchange. Recent studies of forest trees have demonstrated that latent reduction of photosynthetic capacity can begin in the early morning, preceding the midday depression. We investigated whether such early morning reduction also occurs in an herbaceous species, Oenothera biennis. Diurnal changes of the photosy...

The present study was conducted to assess the physiological and biochemical responses of winter vegetable radish (Raphanus sativus L.) to salinity stress. Salt stress markedly reduced biomass production of both radish varieties. Shoot fresh and dry weights were significantly reduced under salt stress, higher reduction was found at 120 mM NaCl as compared. Salt stress significantly reduced chlor...

The effects of 2 nitrate levels, 14 (CK) and 140 mmol L (T), on the leaf gas exchange variables of cucumber (Cucumis sativus L. cv. Xintaimici) seedlings grown in hydroponic culture were investigated. Photosynthetic lightand CO2-response curves from CK and T seedlings were determined and used for the analysis of photosynthetic capacity. The results showed that nitrate stress resulted in a signi...

Photosynthetic light and temperature response curves were measured seasonally in seedlings of white spruce (Picea glauca (Moench.) Voss) grown for two years in the understory of aspen (Populus tremuloides Michx.) or in the open in central Alberta. Light-saturated rate of net photosynthesis, the optimum temperature for net photosynthesis, transpiration rate, photochemical efficiency, and stomata...

The photosynthetic and respiratory behaviors of two Dunaliella salina strains (IR-1 and Gh-U) were investigated at two temperature treatments and two assay temperatures. Net photosynthetic rate (P ), photonN saturated net photosynthetic rate (P ), irradiance required to Saturate Photosynthetic (SI), respiration and Nmax pigment changes in D. salina strains, containing different chlorophyll (Chl...

salix integra thunb. is a shrub distributed in china along the huai river riparian zone, and plays an important role in water and soil conservation. s. integra shrub land is easily submerged during july to october due to the flooding of huai river. in order to characterize the physiological mechanisms of waterlogging tolerance of s. integra and to help rationally select waterlogging-tolerant sp...

Photosynthetic carbon assimilation by isolated chloroplasts and its associated oxygen evolution were measured simultaneously in a single simplified reaction mixture. Each showed an initial lag prior to the attainment of the maximal rate and the photosynthetic quotient was unity during the period of illumination. Following illumination an oxygen uptake was observed in the dark which was not acco...