温度、CaCl2和光照解除桑树种子次生休眠的效果分析

以黑龙江省农家桑树的种子为试验材料,研究了外源钙浸种、提高温度和光照等对解除桑树种子次生休眠的影响.结果表明,常温(25℃)条件下,25 mmol/L CaCl2浸种24 h,可提高桑树种子的发芽率,其中,未休眠桑树种子的发芽率由81％提高到97％,次生休眠的桑树种子的发芽率由16％提高到44％.在25 mmol/L CaCl2浸种基础上进行不同温度(25,28,30,35,37℃)处理,以及相同温度下照光和遮光处理,进一步探讨次生休眠的桑树种子萌发对温度和光照的响应.结果表明,次生休眠的桑树种子的发芽率、发芽势和发芽指数随着温度的升高呈现先升高后下降的趋势,35℃温度处理的发芽率达到最高,可达90％左右,说明提高温度是解除桑树种子的次生休眠的有效方法.桑树种子萌发对光照不敏感,且照光对桑树种子的根长和茎长生长具有抑制作用.

Preliminary Studies on Temperature,CaCl2 and Releasing Secondary Dormancy in Mulberry Seeds

Taking Heilongjiang Province seedling of mulberry seeds as the test materials,effects of seed soaking with exogenous calcium and improve ment of temperature and light on the cancellation of mulberry seed dormancy were studied.The results showed that at room temperature (25 ℃) under the condition of 25 mmol/L CaCl2 with 24 h,the germination rate of mulberry seed was increase significantly.Among them,the germination rate of the dormant mulberry seeds increased from 81％ to 97％,and the germination rate of the mulberry seeds increased from 16％ to 44％.Different temperature (25,28,30,35 ℃ and 37 ℃) were carried based on 25 mmol/L CaCl2 solution,and under the same temperature illumination and shading treatments,to further explore the secondary dormancy of mulberry seed germination response to temperature and light intensity.The results showed that secondary dormancy of mulberry seed germination rate,germination energy and germination index present a trend of increased first and then decreased with the temperature increasing,germination rate of 35 ℃ treatment reached the highest was 90％,indicating that increasing the temperature is lifting of mulberry seed dormancy of effective methods.The germination of mulberry seeds was not sensitive to light,and the light had inhibitory effect on the root length and stem length of mulberry seeds.