Scientific Reports of the Faculty of Agriculture, Okayama University
Published by the Faculty of Agriculture, Okayama University
ONLINE ISSN : 2186-7755


安井 公一 岡山大学
The process of formation and thickenitg growth of the bulb and tuber ornamental plants was studied by histological procedure.The results may be summarized as follws.1.Easter lily has various types of leaves,such as foliage leaf,scaly leaf and foliage leaf with thickened base.Young leaf primordium of eastrelily has a differentiation potency to develop into either a foliage leaf or a scaly leaf.The first leaf primordium of a daughter bulb defferentiated in the uppermost scaly laef axil of its mother bulb on Nov.18 in Okayama.2.During the rest period,mother cormlets of freesia,the average weight of which was about 1.0g,had five primordia of leaves in their main bud.After growth for eight to nine weeks,remarkable swelling of internodes,between seconds and fourth foliage leaves,was observed.And this was the start of the formation of new corm.The development in diameter of new corm mainly depends on the thickenig growth of the cortex.3.Tuber formation of tuberous begonia was brought by swelling of the hypocotyl,under short day condition.Rapid thickening growth of tuber under short day conditions was mainly caused by cell enlargement.4.Tuber formation of cyclamen was brought about by swelling of hypocotyl.Eighty days after sowing,a ring of secondary bundles originated in the pericycle was observed around the primary hypocotyl bundle.In the same manner,130 days after sowing,a tertialy ring of bundles appeared outside of the secondary bundles.The secondary thickening growth of tuber was mainly caused by an increase of xylem parenchyma in the stele.5.At the initial stage of corm development in gladiolus,an increase in the number of cell depend on the activity of apical meristem.But succesive thickening growth was caused by the active division of cells which diffuse in storage tissue of cortex.
easter lily
tuberous begonia