Photosynthesis and Carbohydrate Metabolism in Detached Leaves of Lolium Temulentum L.

S ummary Mature leaves of Lolium temulentum L. remained photosynthetically competent for some days following excision. During this time, amounts of soluble carbohydrate rose markedly and there was substantial accumulation of sucrosyl‐fructans. Cell‐free extracts of excised leaves showed enhanced ability to synthesize oligofructosides from sucrose in vitro . Excised leaves were capable of the synthesis of fructans from exogenous sucrose applied in the dark. Exposure of leaves to 14 CO 2 immediately following excision led to movement of radioactivity from sucrose into higher oligosaccharides and the distribution of 14 C suggested the presence of multiple pools of sucrose within the leaf. These results are discussed in relation to the control of reserve accumulation during periods of fluctuation in sink demand.