以沙芥种子(含水量4.5%)和斧形沙芥种子(含水量4.3%)为材料,采用硅胶干燥法将其含水量分别降至3.1%、2.2%、1.3%,在50 ℃、35 ℃和20 ℃条件下密闭贮藏1年,研究贮藏温度和超干处理对种子萌发指标、解剖结构的影响,为种子老化及贮藏研究提供理论参考。结果表明:(1)随着贮藏温度升高和种子含水量降低,沙芥和斧形沙芥种子的发芽率、胚根长、胚根干质量均在下降。(2)解剖观察发现,贮藏温度升高和种子含水量降低,首先加剧种子胚内部维管束组织活性的降低,其次由里及外对薄壁细胞活性和结构产生破坏,同时胚淀粉粒活性和数量下降。(3)沙芥和斧形沙芥种子分别在含水量4.5%和4.3%(CK)、并于20℃~35℃条件下贮藏后,种子的萌发和结构活性保持最好,而且斧形沙芥种子的保持能力强于沙芥。
The effects of storage temperature on germination index,anatomy structure of ultradried seeds of Pugionium Gaertn.were studied by reducing the moisture content of P.cornutum (L.) Gaertn.and P.dolabratum Maxim.to 3.1%,2.2%,1.3%,respectively from the initial content by silica gel,and aged at 50 ℃,35 ℃ and 20 ℃ for 1 year,which would provide theoretical basis for aging and storage of the seed.The results indicated that:(1)The germination percentage,radicle length,radicle dry weight of P.cornutum (L.) Gaertn.and P.dolabratum Maxim.seeds decreased.(2)The activity of vascular tissue was first decreased and then the structure of parenchyma cell was destroyed by anatomical observation and assay,at the same time,starch granule activity and quantity decreased with the rising of the temperature and declining of the moisture content respectively.(3)After aging treatment between 20 ℃ and 35 ℃,seed germination and the activity of structure of the seed with initial moisture content of P.cornutum (L.) Gaertn.and P.dolabratum Maxim.seeds are 4.5% and 4.3%(CK),respectively were the best in all ultradried seeds.The ability of maintaining activity of P.dolabratum Maxim.seed was greater than that of P.cornutum (L.) Gaertn.seeds.