Light availability has a profound effect on plant growth and development. One of the ways to study the effects of light intensity on plant growth and development without the confounding problem of photosynthate availability is sucrose injection/supplementation. A greenhouse experiment was conducted to evaluate the effects of light levels (0% and 75% shade) and sucrose injection (distilled water...

The economy of C and N in nodulated cowpea (Vigna unguiculata [L.] Walp.) was described in terms of fixation of CO(2) and N(2), respiratory losses of C, and the production of dry matter and protein.Net daytime gain of C by the shoot (net photosynthesis) rose to a maximum at flowering and then declined sharply due to abscission of leaves. Maximum N fixation occurred 10 days prior to maximum net ...

The relative contribution of nitrogen (N) reserves from seeds or uptake by the roots to the growth and N content of young seedlings has received little attention. In this study, we investigated the contribution of N from the acorn or uptake by the roots to the N content of holm oak (Quercus ilex L.) seedlings and determined if remobilization of acorn N was affected by nutrient availability in t...

Barley HvPIP2;1 is a plasma membrane aquaporin and its expression was down-regulated after salt stress in barley [Katsuhara et al. (2002) Plant Cell Physiol. 43: 885]. We produced and analyzed transgenic rice plants over-expressing barley HvPIP2;1 in the present study. Over-expression of HvPIP2;1 increased (1) radial hydraulic conductivity of roots (Lp(r)) to 140%, and (2) the mass ratio of sho...

Manganese deficiency in wheat has become an important nutritional disorder particularly in alkaline calcareous soils where rice-wheat rotation is followed. This experiment was aimed to study the mechanism of Mn efficiency during various developmental stages in six wheat cultivars grown at two Mn levels viz. 0 and 50 mg Mn kg(-1) soil (Mnapplied as MnSO4 x H20) in pots. The Mn vegetative efficie...

Eastern gamagrass, Tripsacum dactyloides L., has been reported to tolerate a wide variety of soil conditions, including drought, flooding, and acidity, but its specific tolerance to aluminum (Al) has not been tested. One strain of this species, PMK Select Lot 94 SFG-1, was tested for its tolerance to excess Al in an acid, Al-toxic Tatum subsoil (clayey, mixed, thermic, Typic Hapludult) and in n...

Leaf product~on, shoot demography and rhlzome growth and branchlng were quantified for the common seagrass specles In a muted seagrass bed on the Bollnao leef flat (Luzon The Ph~l lpplnes) to assess the contribution of these s p e c ~ e s to canopy maintenance meadow biornass and productlvlty We tested the hypothesis that seagrass growth rates correlated negatively with shoot size and age when ...

The growth and metal uptake of two willow clones (Salix fragilis 'Belgisch Rood' and Salix viminalis 'Aage') was evaluated in a greenhouse pot experiment with six sediment-derived soils with increasing field Cd levels (0.9-41.4 mg kg-1). Metal concentrations of eight elements were measured in roots, stems and leaves and correlated to total and soil water metal concentrations. Dry weight root bi...