光与激素对于杜鹃花种子发芽的作用

本文报道24种杜鹃花种子的光照发芽试验,结果表明杜鹃花种子是需光性种子。所有种子的发芽都必须有光照,假如在黑暗条件下进行发芽试验,种子的发芽率几乎等于零。杜鹃花种子的发芽受光敏素的控制,红光促进种子发芽,远红光可以逆转这种促进作用,种子发芽与否取决于最后一次照射的光质。 不同种的杜鹃花种子对光的敏感性存在差异。敏感的种子可以在蓝光,短光照时间下正常发芽,并且它们的需光要求可以被1000 ppm赤霉素所代替。迟钝的种子发芽则要求红光和长光照时间,1000 ppm赤霉素不能代替光,光和赤霉素并用具有增效作用。

INFLUENCE OF LIGHT AND HORMONE ON GERMINATION OF RHODODENDRON SEEDS

The present paper reports the light germination tests on the seeds of 24 speeies of Rhododendron. The main conclusions are as follows.The seeds of Rhododendron are light-requiring seed. Germination of all the seeds needs light, if the seeds are tested in darkness, the germination percent will be almost zero. Germination of Rhododendron seeds is controlled by phytochrome. Red light promotes the germination. The promoting effect is reversed by far red light. The germination response depends on the light qulity of the last irradiation.There are differences of light sensitivity among species of Rhododendron. The seeds of sensitive species normally germinate under blue light and short light period. Their light requirtment is substituted by 1000 ppm GA. The seeds of dull species need red light and long period to germination. 1000 ppm GA doesn't substitute for light, both light and GA are synergistic in dull seeds.