PARENT SESSION
Posters P6D Crop photosynthesis, agricultural biotechnology. Abstracts (742-753)

CO₂ assimilation, architectonics and productivity of wheat genotypes in sowing. Jalal Aliyev^*,1, ¹ Patamdar shosse 40, Baku, Azerbaijan

ABSTRACT- Genotypes with vertically oriented short and narrow leaves (20-30 cm²), high specific surface density (SSD) - 600 mg/cm², with stable and long intensive CO₂ assimilation (30-40 mg/dm²x h) and a high tolerance to water stress form to 10 t/h grain yield. Genotypes with week acceptor ability but a favourable architectonics do not posses an intensive CO₂ assimilation. Width and surface parameters are threefold differed in the genotypes with wide and narrow leaves. About 60% of grain protein synthesis of different genotypes in sowing occurs at the expense of ear photosynthesis. The contribution of ear photosynthesis in grain formation and protein synthesis is essential and varies in a wide range in genotypes. The most intensive CO₂ assimilation is observed during the end of spring tillering before stalk emergence and in a phase of milk ripeness and consists 30-40 mg/dm² x h in the apical leaves of genotypes. Genotypes with a favourable architectonics have relatively high CO₂ assimilation during all period of grain formation. Vertically oriented small leaves creating an optimal architectonics promote a relative high CO₂ assimilation of functioning leaves of all stories for a long time of crop formation. There are high- productive genotypes among plants with C₃ - photosynthesis and low- productive among plants with C₄- photosynthesis. There is a parallel increase in the intensity of real photosynthesis and photorespiration in leaf ontogenesis. A numerous distinct experiments have shown that high productivity was characterized by high intensity both of photosynthesis and of photorespiration. Therefore, in contrast to the conception of photorespiration wastefulness, attempts to reduce its intensity with the purpose of raise of productivity are insolvent.

KEY WORDS: morphophysiological signs, wheat, CO₂ assimilation, productivity