Warming due to global climate change is predicted to reach 2°C in tropical latitudes. There is an alarming paucity of information regarding the effects of air temperature on tropical agroecosystems, including foraging pastures. Here, we investigated the effects of a 2°C increase in air temperature over ambient for 30 days on an established tropical pasture (Ribeirão Preto, São Paulo, Brazil) do...

Growth of two species of marine microalgae, namely Nannochloropsis gaditana Lubián (Eustigmatophyceae) and Nannochloris maculata Butcher (Chlorophyceae), was investigated in cultures submitted to three different concentrations of dissolved inorganic carbon (DIC). Cultures of N. gaditana grown in the absence of DIC in the medium and aerated with less than 0.0001% (v/v) CO2 in air (low DIC condit...

Crassulacean acid metabolism (CAM) was investigated in leaves and stems of the succulent C(4) dicot Portulaca oleracea L. Diurnal acid fluctuations, CO(2) gas exchange, and leaf resistance were monitored under various photoperiod and watering regimes. No CAM activity was seen in well watered plants grown under 16-hour days. Under 8-hour days, however, well watered plants showed a CAM-like patte...

A nontargeted, comprehensive 2-dimensional gas chromatography-time-of-flight mass spectrometry (GC×GC-TOFMS) method was developed for the analysis of fermented cucumber volatiles before and after anaerobic spoilage. Volatile compounds extracted by solid-phase microextraction were separated on a polyethylene glycol 1st-dimension column and 14% cyanopropylphenyl 2nd-dimension column. Among 314 co...

Effects of atmospheric humidity and soil moisture content on the relative intensity of chlorophyll fluorescence of cucumber (Cucumis sativus L.) exposed to high air temperatures were assessed as a measure of heat stress or injury. 1. After exposure to 25 •Ž (control) and 42•‹, 44•‹ and 46•Ž for two to three hours, the intensity of fluorescence decreased a little at 42•‹ and 44•Ž but markedly at...