On the night transpiration of greenhouse roses under glass or plastic cover
Agricultural Meteorology 30(4): 257-268
Rose plants in pails were weighed at the beginning and end of several nights to determine the rate of transpiration under a range of air temperatures. The data were reduced to obtain the leaf resistance (both sides of the leaf in parallel), its mean being 2400 s m-1 .+-. 30%. Once the night-time leaf resistance is known, the transpiration rate can be calculated from measured values of the leaf area index, the leaf temperature and the ambient temperature and dew-point temperature. If the leaf temperature cannot be measured, it can be estimated from the inside temperature and dew-point temperature, and the outside temperature. A calculated example shows that there is agreement within a factor of 2 between an estimate based on the present model and the rate of night evapotranspiration in greenhouses, as reported in the literature.