Search results for "Assimilate partitioning"
showing 2 items of 2 documents
Ozone-induced reductions in below-ground biomass: an anatomical approach in potato
2010
[EN] Potato plants were grown in open-top chambers under three ozone concentrations during two complete cropping seasons (93 and 77 d in 2004 and 2005, respectively). The effects of chronic exposure to ozone on leaf anatomy, cell ultrastructure and crop yield were studied. Severe cell damage was found, even at ambient ozone levels, mainly affecting the spongy parenchyma and areas near the stomata. Damage to the cell wall caused loss of cell contact, and loss of turgor pressure due to tonoplast disintegration, contributed to cell collapse. Phloem sieve plates were obstructed by callose accumulation, and damaged mesophyll cells increased their starch stores. Tuber yield fell sharply (24–44%),…
Upscaling leaf gas exchange measurements to the whole grapevine canopy: An update
2009
This review first revisits current knowledge about single-leaf function, viz. photosynthesis, chiefly in relation to environmental factors, that underscores the importance of multiple summer stresses. Emphasis is placed on the response different genotypes show under light and heat stress with or without soil-water shortage. Secondly, it tackles the thorny issue of extrapolating single-leaf readings to the whole-canopy level, with special reference to both methodological and physiological implications. Whole-canopy gas-exchange systems deliver and emphasise the usefulness of such an approach in achieving key research goals. One case in point is quantifying the amount and dynamics of canopy g…