본 연구는 스프링클러식 관개에서 관비재배가 대추 유목의 생육 및 토양 화학적 특성에 미치는 영향에 대하여 알아보고자 수행하였다. 2012년에 1년생 대추나무를 시험포장에 식재하고 2012년부터 2013년까지 시험을 수행하였다. 시험처리는 토양검정 추천 시비량을 기준으로 관비 50%, 관비 75%, 관비 100%, 관비 125%, 관비 150%와 고형 비료 100%처리를 두었다. 대추나무의 줄기 길이 및 줄기 직경은 관비 125% 및 150%에서 가장 좋았다. 8월에 채취된 대추나무 잎의 T-N, P, K, Ca 및 Mg의 함량은 각각 21.7~ 25.5 g/kg, 1.97~ 2.10 g/kg, 26.8~ 30.5 g/kg, 7.64~ 8.71 g/kg, 2.31~ 3.05 g/kg 범위에 있었다. T-N, P, K 및 Mg함량은 8월에 채취된 잎에서 10월에 채취된 잎 보다 많았다. 2013년 시험후 토양은 시험전 토양에 비하여 pH는 낮아지고 EC, 질산태 질소 및 치환성 칼륨은 다소 높아졌다.

Nitrate in edible vegetables is converted to nitrite by nitrate reductase(NR) and/or bacteria in intestines. Nitrite and amino, in the intestine of some animals and human, bind to form nitrosamine, which is toxic and known as carcinogen. This study was carried out to examine the effect of added chlorides and their concentrations on growth, yield and nitrate content in leaf lettuce plants in hydroponics. Seeds of lettuce cv, "Samsunjokchukmyon" were planted on April 29, and seedlings were planted on June 2, and were cultured until July 5 in 1998. KCI and CaCl₂ were used as chloride source and their concentrations were 1, 2 and 4 me/L, respectively, in the lettuce standard nutrient solution for National Horticultural Research Institute(NHRI). Completely randomized design with 3 replications was used. Nitrate content and NR activity were measured 2 and 5 weeks after planting(WAP). The obtained results were summarized as the follows : Leaf weight per plant was difference from harvest dates and treatments, but total leaf weight was not significantly different among treatments. Number of leaves was higher in KCI 2 me/L, CaCl₂1 me/L and control at 2 WAP than the others, and was higher in KCI 1 me/L, and control at 3 WAP than others, and was higher in control at 5 WAP. Total number of harvested leaves was the highest in control with 14, which followed by KCI 2 me/L and CaCl₂1 me/L. Nitrate content was decreased by addition of chloride in nutrient solution. Nitrate content in the 3rd and 9th leaves was significantly decreased. NR activity was higher in control and CaCl₂ addition treatments, while KCI addition treatments reduced NR activity. However, no direct relationship with nitrate was observed. Growth characteristics such leaf length and leaf width were not significantly influenced by chloride addition.