Dry matter production and photosynthesis of Hordeum vulgare L. in the field.
DM production ranged from <2 g/m2 day in winter to 20 g/m2 day in spring in barley cv. Sekitori-Sai No.1 sown in 15-cm bands 55 cm apart with 105 plants/m of length when established. Photosynthetic rates for given light flux densities were linearly related to LAI except on cold days when rates were suppressed. Night temperatures of <0 deg C reduced the subsequent daily net photosynthesis by about 20%. Dark respiration rate increased with increase in temperature, representing 5-20% (and >20% in May) of daily net photosynthesis.