leaf hydraulic conductance, components of tissue water potential, hydraulic architecture parameters and xylem embolism were examined in greenhouse-grown two-year-old Aleppo pine (Pinus halepensis Mill.) seedlings from six origins representing the geographic range of the species in Italy. Cortical resin composition of the seedlings was also determined. Measurements were made on well-watered seed...

in order to study the effect of natural antitranspirant compound and water stress on growth, development and essential oil content of ocimumbasilicum a factorial experiment based on completely randomized design with three replicates was conducted. 3 levels of water stress (500 as control, 375 and 250 ml/day) and 3 antitranspirant compound (chitosan, plantago mucilage and psyllium mucilage) in 3...

Midday leaf CO2 exchange rate (CER), concentration of chlorophyll (Chl) and soluble protein and activity of the primary enzymes involved in leaf photosynthesis and sucrose metabolism were determined during leaf ontogeny for sugarcane plants grown at ambient (360 mmol mol ) and double-ambient (elevated, 720 mmol mol ) CO2. Although leaf CER of both CO2 treatments increased and was highest at 14 ...

Crop models are being increasingly used in agricultural and environmental studies of marginal environments where water availability limits crop growth. The PNUTGRO model (a precursor of CROPGRO and CSM) has systematically underestimated rainfed pod yield and aboveground biomass, while accurately predicting the same variables under irrigation, in the frequently drought-stricken Argentine peanut-...

Plants are constantly facing rapid changes in evaporative demand and soil water content, which affect their water status and growth. In apparent contradiction to a hydraulic hypothesis, leaf elongation rate (LER) declined in the morning and recovered upon soil rehydration considerably quicker than transpiration rate and leaf water potential (typical half-times of 30 min versus 1-2 h). The morni...

Silicon (Si) is taken up from the soil as monosilicic acid by plant roots, transported to leaves and deposited as phytoliths, amorphous silica (SiO2) bodies, which are a key component of anti-herbivore defense in grasses. Silicon transporters have been identified in many plant species, but the mechanisms underpinning Si transport remain poorly understood. Specifically, the extent to which Si up...

Plants are constantly facing rapid changes in evaporative demand and soil water content, which affect their water status and growth. In apparent contradiction to a hydraulic hypothesis, leaf elongation rate (LER) declined in the morning and recovered upon soil rehydration considerably quicker than transpiration rate and leaf water potential (typical half-times of 30 min versus 1–2 h). The morni...

We investigated hydraulic constraints on water uptake by velvet mesquite (Prosopis velutina Woot.) at a site with sandy-loam soil and at a site with loamy-clay soil in southeastern Arizona, USA. We predicted that trees on sandy-loam soil have less negative xylem and soil water potentials during drought and a lower resistance to xylem cavitation, and reach E(crit) (the maximum steady-state trans...