Seasonal patterns of photosynthesis and water use efficiency in broad leaf forage tree species

Seasonal changes in photosynihetie and respiration rates, water use efficiency and economy coefficient were studied in forage tree species, Prunus cerasoides, Celtis australis and Grewia oppositifolia. The net photosynthetic rate declined in autumn and remained low in winter, gradually increased and reached maximum in summer. The overall photosynthetic rate and water use efficiency were high in C. australis, medium in G. oppositifolia and low in P. cerasoides. The light saturation photosynthesis at high temperature were higher in C. australis followed by G. oppositifolia. The dark respiration was also of higher magnitude in C. australis whereas G. oppositifolia had very high economy coefficient indicating its high biomass production potential.