Lysimeteric Evaluation for Transpiration and Carbon Accumulation of Kimchi Cabbage (Brassica rapa L. ssp. pekinensis)

Abstract

An accurate evaluation of transpiration is required for many applications in agricultural and environmental management because crop yields and plant growth are primarily water limited. This study was aimed to determine the transpiration of Kimchi cabbage (Brassica rapa L. ssp. pekinensis) using weighing lysimeter, to evaluate the relationship between transpiration of Kimchi cabbage and meteorological factors such as solar radiation, air temperature, etc., Transpiration was increased as the leaf area increased with the growth stage. Also daily transpiration per unit leaf area was 0.46 ± 0.13 g cm -2 day -1 and there was no significant difference during cultivation period. The maximum transpiration was 132.9 g hour -1 and diurnal changes of transpiration was highly correlated with solar radiation although the maximum transpiration was observed at 17 -23°C air temperature. The ratio of dry matter production to transpiration was 0.33% and carbon accumulation was 0.13%. This result shows that transpiration of Kimchi cabbage seem to be mainly governed by solar radiation energy in clear days and 96% of the water is discharged through transpiration for the heat dissipation. Therefore, weighing lysimeter can be used to measure transpiration accurately and may be useful in interpreting the plant growth.