Acknowledgement
Supported by : 상명대학교
In order to elucidate physiological factors involved in causing the winter injuries of evergreen Japanese rhododendron (Rhododendron obtusum cv. Hinodegiri) and semi-evergreen rhododendron (Rhododendron yedoense var. poukhanense), these studies were conducted from late winter to early spring. The results were summarized as follows; The water potential, water content in stem, water potential and content have continuously increased in both species between February and May. In R. yedoense, shading treatment had 0.3MPa upper water potential and 3% upper water content than the control. Rhododendron obtusum, the treatments with shading had 0.9MPa upper water potential and 11% upper water content that the control. The difference of water balance by treatments could be found in vitality of stem measured by TTC test. Especially R. obtusum in the treatments with shading in has higher vitality than the control. we find that winter damage of evergreen R. obtusum was determined by whether water balance could be recovered from water deficient state during the dehardening period, or not. In order to recover of the water balance, decreasing water loss more important than increasing water supply, and that was effectively acrueved by the treatment with shading.
상록성인 히노데 기리시마 철쭉(Rhododendron obtusum cv. Hinodegiri)과 반상록성인 산철쭉(Rhododendron yeooense var. poukhanense)의 늦겨울부터 초봄까지의 생장상태를 비교하여 이 시기에 발생하는 피해 원인을 규명하고자 실험한 결과는 다음과 같다. Dehardening후 개화기의 관상가치는 산철쭉의 경우 관수처리 및 차광처리에 따른 관상가치에 별다른 차이가 없었다. 그러나 상록성 왜철쭉의 경우에는 특히 차광처리구에서 대조구나 관수처리구에 비해 높은 관상가치를 나타내었다. Dehardening과정의 동사점의 변화는 두 종류 모두에서 2월부터 3월까지의 기간에 급격한 변화가 이루어져 이 시기가 dehardening의 중요한 시기임을 알 수 있었다. 한편 이 시기에 상록성 왜철쭉은 차광처리구에서 대조구에 비해
Supported by : 상명대학교