刺五加种子结构,后熟作用及其细胞化学研究

刺五加种子为扁肾形，种皮由一层细胞构成。种子脱落时，胚处于心形胚期，胚周围的胚乳细胞解体形成囊腔包囊胚，胚细胞原生质浓厚，胚乳细胞中贮存大量蛋白质和脂类，但两者均未见贮存多糖，有萌发潜能的种子只占全部种子的１２．８０％，种子经变温层积处理６个月即可完成后熟过程，其细胞化学特点是：处理１．５个月时胚细胞中开始积累多糖颗粒，至４个月时达最大量并一直保持至种子萌发。试验地种植条件下饱满种子经１８－２０个

STUDIES ON THE STRUCTURE,AFTERRIPENING AND CYTOCHEMISTRY OF SEEDS IN ELEUTHEROCOCCUS SENTICOSUS

Seeds of Eleutherococcus senticosus (Rupr.et Maxim) Maxim are flat kidneyshaped and their seed coats are only composed of one layer of cells.Embryos with abundant proteins in their cells,are just at the heart shaped stage and are capped by sacs formed from degenerating endosperm cells when seeds shed from their maternal plants.Lots of the stored proteins and lipids exist in endosperm cells but no starch grains either in endosperm cells or in embryo cells.The rate of seeds of being able to germinate in total seeds is 12.80%.The afterripening process of the seeds,which are stratified at different temperatures,ends after 6 months and the cytochemistry features of the seeds are that starch grains initiate a stimulation in embryo cells after 1.5 months and are up to the highest content after 4 months till at the germinating stage of seeds.The plump seeds germinate in the field after 18 to 20 months and their germinating rate is 10%;besides,a few starch grains initiate a stimulation in embryo cells after 12 months and reach the highest content at the germinating stage of seeds.Features of the seeds being of worse quality,much lower germination rate and longer time of afterripening in a natural state are a weak link of sexual reproduction of this species.