Abstract
The purpose of this experiment was to investigate optimal ionic concentration of nutrient solution for water culture of young welsh onion (Allium fistulosum). For the purpose of clarification of optimal nutrient concentration to maximize growth of young welsh onion, different nutrient concentrations of Yamazaki's solution for welsh onion seedling $(NO_3^--N\;9.0,\;NH_4^+-N\;3.0,\;PO_4^{3-}-P\;6.0,\;K^+7.0,\;Ca^{2+}\;2.0,\;Mg^{2+}\;2.0,\;and\;SO_4^{2-}-S\;4.4me{\cdot}L^{-1})$ which selected by prior experiment were treated as 0.6, 1.2, 1.8, and $2.4dS{\cdot}m^{-1}$. Increments of fresh weight, dry weight and top length were the highest in 1.2 and, in the next, were placed by the order of 1.8, 2.4, and $0.6dS{\cdot}m^{-1}$ The regression coefficients for the maximal growth of fresh weight of cv. 'Geurnjanguedaepa' and 'Tokyokuro' were $y=-42.091x^2+171.79x+11.047 (R^2=0.8946,\; R=0.9458^*)\;and\;y=-50.069x2+157.58x+15.414(R^2=0.9343,\;R=0.9692^{**})$, respectively, and optimal EC levels according to regression coefficients were 1.68 and $1.57dS{\cdot}m^{-1}$. As the conclusions, optimal nutrient levels far young welsh onion were $1.2dS{\cdot}m^{-1}$ EC in the early growth stage and $1.6\~l .7dS{\cdot}m^{-1}$ in the later growth stage.
실파용으로 적정 양액농도를 구명하고자 수경재배용으로 선발한 '금장외대파'와 '토쿄구로파' 품종을 공시하여 담액식으로 하여 시험을 수행하였다. 양액종류 시험을 통해 선발된 야마자키 처방의 싹파 전용 양액$(NO_3^--N\;9.0,\;NH_4^+-N\;3.0,\;PO_4^{3-}-P\;6.0,\;K^+7.0,\;Ca^{2+}\;2.0,\;Mg^{2+}\;2.0,\;and\;SO_4^{2-}-S\;4.4me{\cdot}L^{-1})$을 이용하여 EC 0.6, 1.2, 1.8, $2.4dS{\cdot}m^{-1}$의 4수준으로 처리한 결과 초장, 구당 생체중과 건물중에 있어서 두 품종 모두 EC 1.2, 1.8, 2.4, $0.6dS{\cdot}m^{-1}$ 순으로 양호하였다. 최대 생체중을 위한 남장외대파와 '토쿄구로파'의 2차 회귀곡선식은 $y=-42.091x^2+171.79x+11.047 (R^2=0.8946,\; R=0.9458^*)$와 y=-50.069x2+157.58x+15.414$(R^2=0.9343,\;R=0.9692^{**})$ 이었고, 이에 따른 적정 양액농도는 각각 $1.68dS{\cdot}m^{-1}$과 $1.57dS{\cdot}m^{-1}$수준이었다. 따라서 실파 수경재배시 생육 초기에는 양액을 $1.2dS{\cdot}m^{-1}$수준의 저농도로 유지하고 정식 후 30일경인 생육 중기 이후에는 $1.6\~1.7dS{\cdot}m^{-1}$수준의 농도로 유지하는 것이 효율적이라 여겨진다.
