Microclimate, Photosynthesis and Growth of Lucerne (Medicago sativa L.). I. Microclimate and Photosynthesis |
| |
Authors: | SHEEHY, J. E. WOODWARD, F. I. JONES, M. B. WINDRAM, A. |
| |
Affiliation: | The Grassland Research Institute Hurley, Maidenhead, Berks. SL6 5LR!["{ddagger}"]("/math/link//Dagger.gif") |
| |
Abstract: | Measurements of microclimate and photosynthesis of lucerne var.Europe were made in the field during the spring of 1976. Themaximum rate of canopy gross photosynthesis (14.3 g CO2 m2h1, I = ) was 2.5 times greater than that of S 24 perennialryegrass at the same LAI. This difference was due to differencesin individual leaf photosynthesis. The photosynthetic rate ofthe youngest fully expanded leaf of lucerne remained constantthroughout the experimental period at 3.6 g CO2 m2 h1(300 W m2). Measurements of soil water potential profiles indicated thatlucerne extracted water from the soil to a depth of at least800 mm, with a region of maximum uptake between 400 and 600mm. This capability, with a moderate mean leaf resistance of460 s m1, conferred a high assimilation efficiency onlucerne, with a mean water use efficiency of 34 g H2O lost pergram of carbohydrate assimilated, compared with 200 g H2O pergram of carbohydrate for S 24. Medicago sativa L, lucerne, photosynthesis, assimilation efficiency |
| |
Keywords: | |
本文献已被 Oxford 等数据库收录! |
|