Cold stratification, temperature, light, GA(3), and KNO3 effects on seed germination of Primula beesiana from Yunnan, China
Cold stratification, temperature, light, GA(3), and KNO3 effects on seed germination of Primula beesiana from Yunnan, China
复制标题
冷层积、温度、光照、GA(3)、KNO3对云南报春种子萌发的影响
DOI：
10.1016/j.pld.2020.01.003
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发表时间：
2020
期刊：
影响因子：
4.8
通讯作者：
Sun Hang
中科院分区：
文献类型：
--
作者：
Yang Li-E;Peng De-Li;Li Zhi-Min;Huang Li;Yang Juan;Sun Hang
小报春是一种有吸引力的野花，特有地分布在中国西南部亚高山/高山地区的潮湿栖息地。这项研究试图了解这种植物如何适应潮湿的栖息地和高海拔。具体而言，我们研究了冷层积、光照、GA 3、KNO 3和温度对蜜蜂种子萌发的影响。在15/5和25/15 °C条件下，KNO 3和GA 3处理的种子发芽率和发芽率均高于对照。未经处理的种子在较高温度（20、25和28 °C）下发芽良好（> 80%），而在较低温度（5、10和15 °C）和极高温度（30和32 °C）下发芽显著降低。而低温层积（4-16周）后，低温（5-15 °C）和高温（30 °C）下的种子发芽率均显著提高，表明蜜蜂种子具有3类非深度生理休眠。冷层积16周的种子，其发芽的基础温度和热时间降低。与相应的恒定温度（10 °C）相比，在波动温度（特别是在15/5 °C）下孵育的冷层积种子在光照下而不是在黑暗中具有显著高的发芽百分比和发芽率。种子在所有温度下都有严格的光照要求，即使在经历冷层积后也是如此;然而，当种子从黑暗转移到光照时，冷层积和温度波动的组合会增加发芽。这种对光和温度的休眠/发芽反应可能是确保发芽仅在春季和土壤表面处/附近发生的机制，从而避免幼苗因冻结、淹没和/或在土壤深处发芽而死亡。
Primula beesianaForr. is an attractive wildflower endemically distributed in the wet habitats of subalpine/alpine regions of southwestern China. This study is an attempt to understand how this plant adapts to wet habitats and high altitudes. Specifically, we examined the effects of cold stratification, light, GA3, KNO3, and temperature onP. beesianaseed germination. KNO3and GA3increased germination percentage and germination rate compared to control treatments at 15/5 and 25/15 °C. Untreated seeds germinated well (> 80%) at higher temperatures (20, 25 and 28 °C), whereas at lower (5, 10 and 15 °C) and extremely high temperatures (30 and 32 °C) germination decreased significantly. However, after cold stratification (4–16 weeks), the germination percentage ofP. beesianaseeds at low temperatures (5–15 °C) and the germination rate at high temperatures (30 °C) increased significantly, suggesting thatP. beesianahas type 3 non-deep physiological dormancy. The base temperature and thermal time for germination decreased in seeds that were cold stratified for 16 weeks. Cold-stratified seeds incubated at fluctuating temperatures (especially at 15/5 °C) had significantly high germination percentages and germination rates in light, but not in dark, compared to the corresponding constant temperature (10 °C). Seeds had a strict light requirement at all temperatures, even after experiencing cold stratification; however, the combinations of cold stratification and fluctuating temperature increased germination when seeds were transferred from dark to light. Such dormancy/germination responses to light and temperature are likely mechanisms that ensure germination occurs only in spring and at/near the soil surface, thus avoiding seedling death by freezing, inundation and/or germination deep in the soil.