脱水处理对中国无忧花种子萌发的影响

The Effect of Dehydration Treatment on the Germination of Saraca dives Seeds

为探讨中国无忧花Saraca dives种子的脱水敏感性和顽拗性,以成熟种子为材料,研究了脱水处理对种子萌发的影响。将中国无忧花种子进行风干脱水处理,测定种子的千粒重、含水量、发芽率及丙二醛(MDA)、可溶性糖含量、过氧化氢酶(CAT)、超氧化物歧化酶(SOD)活性。结果显示:脱水程度越高,种子的发芽率逐渐降低;丙二醛含量快速上升,后来由于可溶性糖的渗透调节及激活SOD、CAT等酶保护系统,其含量逐渐下降但仍维持在较高水平。脱水后期,由于膜系统被破坏和酶保护系统超过极限,对种子造成了严重伤害。中国无忧花主要分布在热带、亚热带地区;种子千粒重高;含水量高;具有明显脱水敏感性。这些特征表明:中国无忧花种子为典型的顽拗性种子,在种子储存和生产繁育中应予以重视。

To investigate the dehydration sensitivity and recalcitrance of Saraca dives seeds,the effects of dehydration treatment on seed germination were studied with mature seeds as materials.The seeds of S.dives were air-dried and dehydrated,and the 1000 grain weight,water content,germination rate,Malondialdehyde(MDA),soluble sugar content,Catalase(CAT),Superoxide dismutase(SOD)activities of the seeds were measured.The results showed that the higher the degree of dehydration,the lower the germination rate of the seeds.The content of Malondialdehyde increased rapidly.Later,through the osmotic regulation of soluble sugar and the activation of SOD,CAT and other enzyme protection systems,the content gradually decreased but remained at a high level.In the later stage of dehydration,the membrane system was damaged and the enzyme protection system exceeded its limit,causing serious damage to the seeds.The S.dives were mainly distributed in tropical and subtropical regions,with high thousand seed weight,high water content,and obvious dehydration sensitivity.These characteristics indicate that S.dives seeds were typically recalcitrant and should be taken seriously in seed storage and production.