Optimizing Electrical Conductivity and pH of Nutrient Solution for Hydroponic Culture of Seed Potatoes (Solarium tuberosum)

摘要

Potatoes (Solarium tuberosum L. 'Superior', 'Atlantic', and '.lasim') were grown in the nutrient solution to investigate the possibilities for seed tuber production. The optimum range of electrical conductivity (EC) and pH based on their nutrient uptake, growth responses, and tuberization were determined. Decreased absorption of total-N, P, Ca, and Mg, particularly in leaves, was ascribed to the decrease of transpiration rate in the high EC nutrient solution. Shoot growth increased with increasing solution EC in the range of 0.6 to 2.4 dS centry to m~(-1) in both cultivars 'Superior' and 'Jasim', while tuber growth did not show a similar tendency. Tuber growth of medium-early maturing 'Superior' increased with increasing solution EC, while that of late-maturing 'Jasim' was highest in 1.2 dS centry to m~(-1) solution and then declined rapidly. Growth responses such as photosynthetic rate and shoot and root growth slightly increased with the increase of solution pH, but there was no significant difference among the pH levels 5 to 7 in both 'Superior' and 'Atlantic'. Considering above results, medium-early maturing cultivar ('Superior') had a good adaptability in a relatively wide range of solution EC (0.6-2.4 dS centry to m~(-1)), while it showed very sensitive growth responses to acidic nutrient solution. Mid-late maturing cultivars ('Jasim' and 'Atlantic') showed opposite responses to medium-early maturing cultivars.