Effects of Shading on the Growth and Development of Ophiopogon japonicus

Abstract

The aim of the paper is to study the growth and development of Ophiopogon japonicus under various shading conditions. O. japonicus is often used as a groundcover plant in japanese gardens. And it is a “shade plant” adaptable to a wide range of light intensities. Light intensities in three treated plots were 1%, 10% and 48% of full sunlight. Investigations also were made for the growth and development of plants in the habitat. O. japonicus usually grows in shadowy habitats such as broad-leaved forests or Charnaecyparis obtusa stands on Mt.Handa.
The total plant fresh weight during the whole period causes the average increases of 0.5g, 7.4g and 15.9g in 1%, 10% and 48% plots respectively. As for other growth indices, the values in 48% plot are generally superior to those in 10% plot, followed by those in 1% plot. In 48% plot, the, vigorous growth is observed at each index of stock and daughter plants. In 10% plot, the favorable. growth per total plant is attributed to the growth of daughter plants. In 1% plot, the growth of leaves, per total plant increases, whereas roots decaysomewhat.
Stock plant harvested in treated plots exhibits a pattern of leaf growth which follows normal typecurve. Normal type curve specifically changes its, slope depending on the level of shading, with imperfect curve of daughter plants which has progressivelythe steep slope with the increase of shade. Stock plant on habitat in Winter exhibits a pattern of leaf growth which follows negative asymmetric type curve and, in Summer, bimodal type curve.