Expression and inhibition of aquaporins in germinating Arabidopsis seeds.

Extensive and kinetically well-defined water exchanges occur during germination of seeds. A putative role for aquaporins in this process was investigated in Arabidopsis. Macro-arrays carrying aquaporin gene-specific tags and antibodies raised against aquaporin subclasses revealed two distinct aquaporin expression programs between dry seeds and young seedlings.

Mechanical stabilization of desiccated vegetative tissues of the resurrection grass Eragrostis nindensis: does a TIP 3;1 and/or compartmentalization of subcellular components and metabolites play a role?

During dehydration, numerous metabolites accumulate in vegetative desiccation-tolerant tissues. This is thought to be important in mechanically stabilizing the cells and membranes in the desiccated state. Non-aqueous fractionation of desiccated leaf tissues of the resurrection grass Eragrostis nindensis (Ficalho and Hiern) provided an insight into the subcellular localization of the metabolites (because of the assumptions necessary in the calculations the data must be treated with some caution).

Relationship between growth and xylem hydraulic characteristics of clones of Eucalyptus spp. at contrasting sites.

To assess relationships between hydraulic characteristics and growth efficiency (expressed as trunk volume increment per unit leaf area per year), we measured xylem specific conductivity, leaf specific conductivity and the vulnerability of xylem to cavitation in branches of 7-8-year-old trees of four closely related Eucalyptus clones growing in plantations on mesic and xeric sites. Growth was influenced more by site than by clone. Hydraulic conductivities were higher in trees on mesic sites than in trees on xeric sites, but within a site, conductivity did not differ among clones.

An ultrastructural study using anhydrous fixation of Eragrostis nindensis, a resurrection grass with both desiccation-tolerant and -sensitive tissues.

The ability of tissues to survive desiccation is common in seeds but rare in vegetative tissues. In this study the ultrastructure of hydrated and dehydrated tissues were examined at different stages of the life cycle of the resurrection grass, Eragrostis nindensis Ficalho & Hiern. Conventional fixation techniques are unsuitable for dry tissues as rehydration occurs during fixation in aqueous fixatives.