Chamber-based system for measuring whole-plant transpiration dynamics.

Most of our insights on whole-plant transpiration are based on leaf-chamber measurements using water vapor porometers, IRGAs, or flux measurements. Gravimetric methods are integrative, accurate, and a clear differentiation between evaporation and can be made. Water vapor pressure deficit (VPD) is the driving force for but assessing its impact has been evasive, due to confounding effects of other climate drivers.

The maize Activator/Dissociation system is functional in hexaploid wheat through successive generations.

The aim of the present study was to provide useful background information and evidence of the functionality of the maize Activator/Dissociation (Ac/Ds) system in hexaploid wheat. Two transgenic parental wheat lines, one harbouring the immobilised Ac element (iAc) and the other the Ds element (pUbi[Ds-uidA]bar), were crossed. Transient GUS assays confirmed that the iAc transposase is active in hexaploid wheat.

Effects of drought during grain filling on PS II activity in rice.

The Rice varieties Araure 4 (A4) and Fonaiap 2000 (F2000) were grown in the glasshouse under natural sunlight and subjected to drought at heading. The drought induced changes in chlorophyll a fluorescence parameters, pigment composition, D1 contents and carbohydrate accumulation were investigated. Drought decreased phiPS II, FV'/FM' and qP, and increased qN in both varieties.

Operation of the xanthophyll cycle and degradation of D1 protein in the inducible CAM plant, Talinum triangulare, under water deficit.

Changes in photochemical activity induced by water deficit were investigated in Talinum triangulare, an inducible CAM plant. The aim was to analyse the interactions between C3 photosynthesis, induction and activity of CAM, photosynthetic energy regulation and the mechanisms responsible for photoprotection and photoinhibition under water stress. Gas exchange, chlorophyll a fluorescence, titratable acidity, carotenoid composition and relative contents of the PSII reaction centre protein (D1) were measured.