九里香种子脱水耐性和萌发生理的研究

九里香种子自花后 42～ 77d,含水量和电导率逐渐降低 ,种子干重、发芽率、发芽指数和活力指数逐渐增加。硅胶脱水 1～ 6d后 ,种子含水量下降 1 0 %～ 3 5 % ,发芽率、发芽指数和活力指数均有不同程度的降低 ,不同发育时期九里香种子的脱水耐性有别 ,花后 42～ 70d不断增强 ,77d有所减弱。花后 70d的种子含水量降至 1 0 % ,种子发芽率无明显降低 ;含水量为 9%的种子在 4°C和 2 0°C的低温条件贮存 3 0d和 42d ,多数种子仍能萌发 ,这表明九里香种子是一种正常型种子。光照能促进种子的萌发 ;在 2 0～ 3 0°C、室温和 2 0 /3 0°C变温条件下种子萌发较好 ;光照和温度对种子萌发有单独影响 ,但又相互作用 ,同时光照对萌发的影响还与种子含水量有关。

Study on desiccation-tolerance and germination physiology of Murraya paniculata seeds

Seed dry weight, germination percentage(GP),germination index(GI)and vigor index(VI)of Murraya paniculata rose gradually with the seed developing time from 42 DAA(days after anthesis)to 77 DAA,but the seed moisture content(MC)and electric conductivity rate decreased at the same time. The seed MC decreased by 10%～35% after desiccating with silica gel for 1～6 days,GP,GI and VI decreased to various degrees. The desiccation-tolerance of seeds at different stages was different and it rose gradually from 42～70 DAA,then decreased at 77 DAA. The GP of seeds at 70 DAA had no various decrease when the MC was reduced to 10% and most of seeds with 9% MC could germinate after storing at the 4 °C and -20 °C for 30 and 42 DAA,so this result showed Murraya paniculata seeds were orthodox seeds. Light could accelerate germination and the seeds germinated better at 20～30 °C,ambient temperature and 20/30 °C than at other temperatures. The effects of light and temperature on the germination were independent as well as interrelated and also related to seed MC.