Long-term effects of light quality on leaf hydraulic conductance (K(leaf)) and stomatal conductance (g(s)) were studied in cucumber, and their joint impact on leaf photosynthesis in response to osmotic-induced water stress was assessed. Plants were grown under low intensity monochromatic red (R, 640 nm), blue (B, 420 nm) or combined red and blue (R:B, 70:30) light. K(leaf) and g(s) were much lo...

Leaf vein traits are implicated in the determination of gas exchange rates and plant performance. These traits are increasingly considered as causal factors affecting the 'leaf economic spectrum' (LES), which includes the light-saturated rate of photosynthesis, dark respiration, foliar nitrogen concentration, leaf dry mass per area (LMA) and leaf longevity. This article reviews the support for ...

Overexpression of genes that respond to drought stress is a seemingly attractive approach for improving drought resistance in crops. However, the consequences for both water-use efficiency and productivity must be considered if agronomic utility is sought. Here, we characterize two tomato (Solanum lycopersicum) lines (sp12 and sp5) that overexpress a gene encoding 9-cis-epoxycarotenoid dioxygen...

Circadian resonance, whereby a plant's endogenous rhythms are tuned to match environmental cues, has been repeatedly shown to be adaptive, although the underlying mechanisms remain elusive. Concomitantly, the adaptive value of nocturnal transpiration in C3 plants remains unknown because it occurs without carbon assimilation. These seemingly unrelated processes are interconnected because circadi...

Tropical hyperseasonal savannas provide a rare example of a tropical climax community dominated by graminoid species. Species living in such savannas are frequently exposed to excess heat and light, in addition to drought and waterlogging, and must possess traits to avoid or tolerate these stress factors. Here we examine the contrasting heat and light stress adaptations of two dominant savanna ...

Ecophysiological characteristics of "Ahmadaghaii" "Ohadi" "Kallehghuchi" cultivars (as scions) on four pistachio rootstocks (Pistacia vera Cv. Badami riz, P. vera Cv. Sarakhs, P. atlantica sub sp. Mutica, P. atlantica sub sp. Atlantica) were evaluated during the spring and summer seasons of 2005 in the Iran's Pistachio Research Institute (IPRI). Ecophysiological characteristics such as photosyn...

Laboratory expenments were conducted to evaluate the effects of increased so11 salinity on gas exchange functlonlng and growth of the braclush-marsh grass Spartlna patens (Alt) Muhl under controlled soil redox potentials (Eh) which were malntalned at either aerobic (+489 mV) or hypoxlc (-40 mV) conditions Plants were subjected to salinities of 0 5, 15 and 25 ppt gradually over a 7 d penod and l...

A new high pressure flow meter (HPFM) method for measuring plant hydraulic conductances (K) was investigated to examine whether its results are comparable to those from a conventional evaporative flux (EF) method in crops. Hydraulic conductance (K) was measured by the two methods under quasi-steady-state conditions in six crops grown in pots: soybean (Glycine max L. Merr. cv. Tsurunoko daizu), ...

Developmental mechanisms that enable perception of and response to the environment may enhance fitness. Ecophysiological traits typically vary depending on local conditions and contribute to resource acquisition and allocation, yet correlations may limit adaptive trait expression. Notably, photosynthesis and stomatal conductance vary diurnally, and the circadian clock, which is an internal esti...