작약 식재후(植載後) 1년생은 일반관리법으로 재배하고 2년생부터 4년생 까지 3년간은 지상부 병해(病害)에 약제(藥劑)를 전혀 살포하지 않고 조기고사된 작약과 1년에 4회씩 3년간 적용약제를 살포하여 정상생육한 작약을 7월 25일부터 10월 25일까지 한 달 간격으로 4회 수확하여 조사한 결과 약제무방제에 따른 조기고사의 경우 건근수량(乾根收量)이 7월 하순경에 일찍 수확한 것은 1,126kg/10a 로 10월 하순 수확 1,177kg/10a에 비해 차이가 없으면서 paeoniflorin 함량이 가장 높았고, 약제방제에 따른 정상생육의 경우 수확 시기를 조정하여 10월 하순에 늦게 수확하는 것이 paeoniflorin 함량은 7, 8월 수확보다 낮았지만 건근수량(乾根收量)은 1,650kg/10a로 7월 수확 1,242kg/10a 에 비해 33% 증수(增收)되었다. 따라서 고품질 다수확을 위해서 는 작약 지상부병해에 약제를 살포하지 않고 일찍 고사시킬 것이 아니라 약제방제를 철저히 하여 지상부 생육을 10월 하순까지 유지하는 것이 필수적이었다.
Changes of yield and paeoniflorin content according to chemical control and harvest time were investigated. Peonies were harvested after four years from planting. Disease and pest control method was applied normally in first year. From second year to forth year we set two blocks and controlled them differently. In one, peonies were withered early under non-control condition. In the other which was controlled by spraying chemicals four time a year, top part withering was delayed. Harvest was taken four times top part withering was delayed. Harvest was taken four times: Jul. 25, Aug. 25, Sep. 25, and Oct. 25. In non-chemical, at harvest of Jul. 25, paeoniflorin content was highest and dry root weight was 1,126kg/10a which was little less than 1,177kg/10a of Aug. 25. In chemical control, dry root yield of Oct. 25. showed an increase of 33% over that of Jul. But paeoniflorin content in root at Oct. was lower than at Jul. or Aug. For high qualities and harvest yields of peony root, chemical control is necessary to maintain top part to late in Oct.
