Reduction of Stem Cavity and Improvement of Flower Quality in Chrysanthemum 'Baekma' by Hydroponic Culture

양액재배에 의한 국화 '백마'의 줄기공동 경감과 절화품질 향상

This study was conducted to investigate effect of ionic strength and feeding times of a nutrient solution on reduction of stem cavity size and improvement of flower quality in chrysanthemum 'Baekma'. A nutrient solution was applied with different strengths at three stages, namely, transplanting, budding, and flowering. The solution EC was adjusted as 1.61.82.0, 1.81.81.8, 1.82.01.8, and $2.02.02.0dS{\cdot}m^{-1}$ in four treatments. Feeding frequency per a day were 4 times for 12 min., 8 times for 6 min., 12 times for 4 min., and 18 times for 2.7 min. each. Cut flower length as affected by different strengths of a nutrient solution was the greatest in the plot of EC $2.02.02.0dS{\cdot}m^{-1}$. However number of leaves, stem diameter, and leaf size were greater in EC $1.82.01.8dS{\cdot}m^{-1}$ than in other treatments. Also, petal number of petals was the greatest and stem cavity size was the smallest in the plot of EC $1.81.81.8dS{\cdot}m^{-1}$. Plant height, number of leaves, stem diameter, leaf size were greater in the plot with 12 times feed ing per a day. number of petal was most in the plot with 8 times feeding per day, while stem cavity size was the smallest in the plot with 12 times feed ing per a day. Therefore, the better plant growth, the smaller stem cavity size.

본 연구는 직삽 양액재배에 의한 '백마'품종의 줄기 공동화를 경감하고 절화품질 향상시키고자 양액농도 및 공급횟수를 구명하고자 실시하였다. 생육단계별 양액농도 변환은 초기중가후기에 EC $1.6{\rightarrow}1.8{\rightarrow}2.0$, $1.8{\rightarrow}1.8{\rightarrow}1.8$, $1.8{\rightarrow}2.0{\rightarrow}1.8$, $2.0{\rightarrow}2.0{\rightarrow}2.0dS{\cdot}m^{-1}$을 각각 처리하였으며, 양액공급횟수는 l 일 48분을 4, 8, 12, 18회로 각각 나누어 공급하였다. 생육단계별 양액농도에 따른 절화장은 양액농도가 높은 EC $2.0{\rightarrow}2.0{\rightarrow}2.0dS{\cdot}m^{-1}$ 처리가 100.1 cm로 컸고, 엽수, 경경, 엽장, 엽폭은 $EC1.8{\rightarrow}2.0{\rightarrow}1.8dS{\cdot}m^{-1}$ 처리가 가장 양호하였고, 꽃잎수는 $EC1.8{\rightarrow}2.0{\rightarrow}1.8dS{\cdot}m^{-1}$ 처리가 344개/송이로 가장 많았고, 줄기공동 크기도 3.4 mm로 가장 작게 나타나 양호하게 나타났다. 양액공급횟수에 따른 효과는 절화장은 양액공급횟수가 12회/1일 처리가 116.2cm 였고, 엽수, 경경, 엽장, 엽폭도 12회/1일 처리가 가장 양호하였으나, 꽃잎수 8회/1일처리가 336개/송이로 많았고, 줄기공동 크기는 12회/1일 처리가 3.4 mm로 가장 작게 나타나 양호하게 나타났다. 따라서 생육이 좋을수록 줄기공동의 크기는 작아지는 것으로 생각되었다.