水耕トマト栽培における水消費 : Logistic式による数値解析

The amount of water consumed mainly by transpiration in hydroponic culture of tomatoes was measured and analyzed by the least-squares curve-fitting method with the Logistic equation : (Y-A) /([1+exp(B-CT)]). The experimental data fitted well to the equation. Cumulative temperature was more preferable for the independent variable, T, than the day number of cultivation or the cumulative energy of solar radiation. The cumulative temperature at Y=A/2 was evaluated to be 1956±53 deg･day. The A values were equal to 113±3 and 88±4 l per a plant of tomato for the cultivations through spring and autumn seasons, respectively. The flowering of the first truss of tomato began at the cumulative temperature of 1045±38 deg･day, irrespective of cultivation year and season.