壳斗科几种种子脱水和低温敏感性初探

Dehydration and Chilling Sensitivity of Several Fagaceae Seeds

以壳斗科的栓皮栎、麻栎、夏栎、槲栎、锐齿槲栎和青冈种子为研究对象,通过分析其对脱水和低温的敏感性程度来判断种子的贮藏习性。将整粒种子置于室内通风处,进行自然风干,以种子的半致死含水量(LMC50)的高低来判断其脱水敏感性程度。将种子用编织袋包装后直接贮藏于-5℃,定期取出种子检测其活力,以种子活力来判断其低温敏感性。实验表明所选几种种子均对脱水和低温敏感,属顽拗性种子。文中还尝试了开放贮藏、半密闭贮藏和密闭贮藏对种子贮藏效果的影响。结果表明种子贮藏需要保持湿度并保证一定的氧气供应(半密闭),而且需要控制适当的低温。5℃的低温只能一定程度上延缓而不能抑制种子的萌发,可以尝试更低的温度进行种子贮藏。种子的贮藏条件还需要进一步探索。

In this paper we investigated the dehydration, chilling sensitivity and the storage behavior of several Fagaceae seeds, Q. variabilis B1. , Q. acutissima Carruthers, Q. robur L. , Q. aliena Blume, Q. aliena var. acuteserrata Maxim. and C. glauca Overst included. Seeds moisture content （MC） and germination percentage were tested after been air-dried. Lethal moisture content 50% （ LMC 50） is a level of MC, at which level only 50% of the seed are alive. The higher the LMC 50 is, the more sensitive the seed is. The LMC 50 of these seeds were all above 25%, that was seeds were sensitive to dehydration. Seeds were stored under -5 ℃ directly, and seed vigor and MC were tested aperiodically. Chilling sensitivity was judged by seed vigor after storage. Seed vigor reduced after chilling storage for a short time, which meant that seeds were sensitive to chilling. Therefore all these seeds are recalcitrant seeds. We also tested the effects of different storage condition on storage results. We packed seeds with PE net, PP woven bags, aluminum-foil sack in order to create open, semi-airproof, or airproof storage condition respectively. The results indicated that seed should be stored under wet, air-exchange permitting, and appropriate low temperature. Seed germination can only be partly delayed in stead of be restrained under 5 ℃. A lower temperature can be tried in the future. The storage of recalcitrant seeds needs further exploration.