The effect of NO₃ and NH₄ ratio, aeration, solution pH, and temperature on the mineral uptake and growth of hydroponically grown O. stolonifera DC. were studied. The results obtained are as follows:
1. Solution pH lowered rapidly with the time passed.
2. Mineral uptake and growth was the best in the 6 : 6 (me/ℓplot of NO₃ and NH₄ ratio.
3. Withering to death percentage according to the ratio of NO₃ and NH₄ was 98 % at 0 : 12 and that of 3 : 9 was 28%.
4. Better growth was obtained both with the NO₃ and NH₄ ratio 6 : 6 and 9 : 3 although neither of the treatments showed normal plant growth, so the optimum NO₃and NH₄ ratio was considered to be between 6 : 6 and 9 : 3 (me/ℓ).
5. Aeration improved mineral uptake and significantly increased plant height, leaf area, fresh and dry weight.
6. Optimum solution pH and temperature was determined 7 and 25 ℃, respectively.
Growth of hydroponically grown O. stolonifera DC. was affected more by pH than temperature of nutrient solution.
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