珍稀濒危植物石山苏铁种子萌发特性研究

Study on Seed Germination Characteristics of Rare and Endan-gered Plant Cycas miquelii O.Warburg

为更好地保护石山苏铁(Cycas miquelii O.Warburg)资源、扩大石山苏铁种群,本研究以石山苏铁种子为材料,研究种子带皮情况、温度、基质、光照、埋深、土壤含水量对其萌芽率的影响。结果表明:去除种子中种皮的种子发芽率为63.33%,明显高于不去皮时的发芽率(43.33%);温度低于25℃时种子不萌发,在30℃、35℃条件时种子都能萌发,且35℃时能明显加快其幼苗萌发进程和生长速度;在腐殖土中播种的种子萌发率最高,为66.67%,在珍珠岩、黄土、混合土中播种的种子萌发率无显著差异,在沙土中播种的种子萌发率最低;20%、40%的土壤含水量对石山苏铁种子萌发率的影响无显著差异,但40%土壤含水量处理的苏铁幼苗生长更好,80%含水量下种子不萌发。石山苏铁种子基本成熟时就应采收,阴干后及时保存或播种,其最佳发芽条件为去除种子中种皮、温度30-35℃、腐殖土基质、40%土壤含水量,光照、埋深不是石山苏铁种子萌发的必要条件。

In order to better protect Cycas miquelii O.Warburg resources and expand C.miquelii O.Warburg population,C.miquelii O.Warburg seeds were used as the test material to study the effects of with seed coat or without seed coat,temperature,substrate,light,burial depth,and soil moisture content on its germination rate.The results showed that the germination rate of removing mesosperm was 63.33%,which was signifi-cantly higher than that without removing seed coat(43.33%).The seeds did not germinate below 25℃,and the seeds could both germinate at 30℃and 35℃.Moreover the germination process and growth rate of seed-lings could be significantly accelerated at 35℃.The germination rate of seeds in humus soil was the highest with 66.67%,there was no significant difference in the germination rate of seeds sown in perlite,loess and mixed soil,while the germination rate was the lowest in sandy soil.There was no significant difference in the effect of 20%and 40%soil water content on seed germination rate of C.miquelii O.Warburg,but cycad seedlings treated with 40%soil water content grow better,and the seeds did not germinate under 80%water content.The seeds of C.miquelii O.Warburg should be harvested when they were basically matured,pre-served or sowed in time after drying in shade.The best germination conditions were to remove the meso-sperm from the seeds,the temperature was 30-35℃,the substrate was humus soil,and the soil moisture content was 40%.Light and burial depths were not necessary conditions for the germination of C.miquelii O.Warburg seeds.