Abstract
To verify the possibility of growing muskmelons by limited nutrient supply control (LNSC) based on the changing pattern of nutrient uptake, muskmelons were grown in double trough substrate bed from April 28 to July 14, 2006. Three treatments consisting of a combination of fertigation methods and kinds of substrates were as follows; 1) EC-based control in granule rockwool (EC·RW), 2) LNSC in granule rockwool (LNSC·RW), and 3) LNSC in an organic substrate (LNSC·OR). The results showed that the leaf and stem fresh weights under EC·RW were greater than those under LNSC·RW. However, fresh weight and soluble solid content of the fruits did not significantly differ between EC·RW and LNSC·RW. The amounts of total N, PO43−-P, K, Ca and Mg during the whole growing period under LNSC²RW were 883, 362, 492, 398 and 157 me plant−1, and the rates to those of EC·RW were 50, 88, 60, 48 and 38%, respectively. Thus, it was confirmed that muskmelons could be grown successfully without reducing the yield and quality by applying a reduced amount of nutrient elements using LNSC. It was also suggested that the suitable amount of nutrient differs depending on the kind of substrate, because the fruit yield and quality were found to be markedly lower for LNSC·OR than for LNSC·RW.
