Studies on the Physiological and Ecological Characteristics of Korean boxwood(Buxus microphylla var. koreana Nakai)

회양목의 생리적 특성과 엽색변화에 관한 연구

This study was carried out to compare physiological characteristics of winter green cultivar (Buxus microphylla van. koreana 'Hanlim') with those of native cultuvar and clucidate the effect of environmental factors such as light intensity, time of shading, and nutrients etc. on leaf color in Korean boxwood(Buxus microphylla var. koreana Nakai). The results are summarized as followed; The 'Hanlim' cultivar had higher contents of chlorophyll as compared with native cultivar from September, 1989 to March, 1990. However, at April, 1990, native cultivar had higher chlorophyll contents. In the rate of photosynthesis, 'Hanlim' cultivar was higher than native cultivar from September to December, 1989, but showed the opposite trend from March to April, 1990. As to the period of browning, 'Hanlim'cultivar had stayed green even after November 22, 1989, while the foliage of native cultivar turned yellowish brown color through the winter. The contents of nitrogen and potassium of 'Hanlim' cultivar werehigher than those of the native cultivar. However native cultivar had higher rate of phosphorus, magnessium, and calcium. In the effect of environmental factors such as light intensity, time of shading, and nutrients etc. on leaf color in Korean boxwood(Buxus microphylla var. koreana Nakai), chlorophyll contents were increased with shading and leaves grown 70% shading had twice as much as those of full sunlight, fertilized plot. Nutrient fertilization increased chlorophyll contents and values of color in boxwood too. In the shading times, early shading time maintained effectively green color of boxwood in winter. Therefore, in case of native cultivars, it has planted at full sunlight area until now and color of leaves turned yellowish brown color through the witner. However, it will maintain green color of leaves by planting at shade area. In addition to, as 'Hanlim' cultivar had benefits of maintain green color of leaves during winter, it will be planted at full sunlight area to landscape plants.