Wednesday, August 1, 2012
Grand Ballroom
The objective of this study was to investigate how the variation in bicarbonate (HCO3-) concentrations in fertilizer solution change the tissue nutrient content of 'Seolhyang' strawberry plants and chemical properties of root substrate during vegetative propagation. Cold-treated mother plants were transplanted to wooden boxes (30 cm x 30 cm, 20 cm deep) containing coir dust + perlite (7:3, v/v) and fertilized with a modified Hoagland solution containing 60, 90, 120, 180, and 240 mg·L-1 of HCO3- as a constant feed. The electrical conductivity (EC) in the nutrient solution was maintained at around 1.2 dS·m-1 and plants were fertigated as needed. In every two weeks for 126 days after transplanting, root substrate solutions were collected and analyzed for mineral nutrient concentrations by ion chromatography. The tissue analyses were also made 126 days after transplanting for mineral nutrient content on a dry weight basis for the above ground plant parts. During the experiment period, the pH and concentrations of K, Ca, and Mg in soil solution were higher as the concentrations of HCO3- were elevated in nutrient solution. The pH and nutrient concentrations in root substrate solution became different from week 2 with more variation occurring as plants grew. The final pH measured 126 days after transplanting was 5.4, 5.8, 7.3, 7.9, and 8.3, respectively, for treatments with 60, 90, 120, 180, and 240 mg·L-1 HCO3-. But the electrical conductivity (EC) of soil solutions was not significantly different among treatments. Even though the HCO3- concentrations in nutrition solution were elevated from the beginning of the experiment, the HCO3- concentrations in soil solution became different at week 4. The elevation of HCO3- concentration in nutrient solution lowered Fe, Mn, Zn, and Cu contents in the above ground tissue when determined 126 days after transplanting.