background and objectives: septoria leaf blotch disease (stb) caused by the fungus mycosphaerella graminicola (fuckel) j. schroeter (anamorph: septoria tritici roberge), is one of the most destructive foliar diseases of wheat in the world, that its worldwide damage in outburst years is about 30 to 50 per cent. the pathogen is a bipolar heterotallic ascomycete that its sexual life cycle is repea...

Bamboos are arborescent monocotyledons that have no secondary growth, but can continually produce conduits with diameters appropriate to the current size of plant. Here, we studied bamboo hydraulic architecture address mechanisms involved in compensating for increase resistance during ontogeny. We measured weighted vessel (Dh) at different distances from apex along stem Bambusa textilis. The co...

A high capacity for accumulation of Mn was reported for sunflower plants. Localization of excess Mn is therefore of special interest for understanding metal tolerance mechanisms in this species. In this study, structural and histochemical alterations caused by Mn accumulation in leaves were investigated in sunflower (Helianthus annuus L. cv. Azar-ghol) plants grown in nutrient solution. In the ...

(Leaf damage in a mangrove swamp at Sepetiba Bay, Rio de Janeiro, Brazil). Leaf damage to Rhizophora mangle L., Avicennia schaueriana Stapf. & Leechman, and Laguncularia racemosa L. was studied in a two hectare mangrove swamp site in Sepetiba Bay. Seventeen arthropod morphospecies were identifi ed as being responsible for the damage, and their species diversity was highest on A. schaueriana, fo...

Spring gardens will soon bloom with an abundance of flowering plants—from cultivated roses to hillside wildflowers. The diversity among flowering plants is remarkable, and even within a single plant, you find an assortment of shapes and sizes. Plant organs—leaves and petals, for instance—clearly have distinct forms and functions and are subject to different evolutionary pressures. Yet scientist...

The developmental pattern of C4 expression has been well characterized in maize and other C4 plants. However, few reports have explored the possibility that the development of this pathway may be sensitive to changes in atmospheric CO2 concentrations. Therefore, both the structural and biochemical development of leaf tissue in the fifth leaf of Sorghum bicolor plants grown at elevated CO2 have ...

A comparison between Au, TiO2 and self-catalysed growth of SnO2 nanostructures using chemical vapour deposition is reported. TiO2 enables growth of a nanonetwork of SnO2 , whereas self-catalysed growth results in nanoclusters. Using Au catalyst, single-crystalline SnO2 nanowire trees can be grown in a one-step process. Two types of trees are identified that differ in size, presence of a catalyt...

The onset of export during leaf development was correlated with changes in metabolism and ultrastructure and with patterns of solute distribution in the developing seventh leaf of sugar beet (Beta vulgaris L.) in order to study the cause of initiation of translocation. Infrared gas analysis of carbon dioxide uptake showed a broad peak for net photosynthesis dm(-2) at 35 to 40% final laminar len...

Vacuolar water movement is largely controlled by membrane channels called tonoplast-intrinsic aquaporins (TIP-AQPs). Some TIP-AQP genes, such as TIP2;2 and TIP1;1, are up-regulated upon exposure to biotic stress. Moreover, TIP1;1 transcript levels are higher in leaves of a tomato (Solanum lycopersicum) line resistant to Tomato yellow leaf curl virus (TYLCV) than in those of a susceptible line w...