テッポウユリりん茎の生育反応に関する研究

Abstract

The experiment was carried out to clarify the effect of temperature and light treatments on the type of leaves developing from scale bulblets. The Easter Lily cultivar “Hinomoto” was scaled at 25 or 15°C in darkness for 5 months prior to a growth production phase. On 1/15/74 the newly developed bulblets (scale bulblets) were planted in peatmoss and then grown for 75 days at constant temperatures of 25, 20, 15 or 10°C in darkness or in continuous illumination by fluorescent tubes (NEC, FL-20-BR).The development of foliage scales on the scale bulblets was greater in light than in darkness and was independent of the previous scaling or subsequent growing temperature treatments. In light, when the lily was scaled at 15°C, foliage scales developed almost equally regardless of the subsequent growing temperature treatment. When scaled at 25°C, however, the lower the growing temperature was, the greater the development of foliage scales was. Independent of growing temperatures, new bulblets with foliage scales were more numerous when scaled at 15°C than at 25°C.In darkness, bulblets formed foliage scales to a greater degree at 10°C than at any other growing temperature. These foliage scales developed particularly at the end of the experiment. At 25°C (growing temperature), scale bulblets in darkness bolted or developed stems with foliage leaves to the same degree as in light and were independent of the original scaling temperatures. At the growing temperatures of 20, 15 or 10°C, more bolted bulblets were observed when originally scaled at 25°C than at 15°C. At the growing temperatures of 20 or 15°C, bolting occurred to a greater degree in light than in darkness.These results indicate the following: 1) When new bulblets are devoloped at a higher temperature, they bolt more easily than when developed at a lower temperature and the coolly formed bulblets tend to develop foliage scales. 2) Light during bulblet growth induces the bulblet to form foliage scales and this light response is promoted by low temperature. 3) In darkness, a growing temperature of 10°C induces foliage scale development.