盐胁迫对2种珍贵速生树种种子萌发及幼苗生长的影响

以1/2Hoagland营养液为基础培养液,研究了在0.1%、0.2%、0.4%和0.6%NaCl胁迫条件下,毛红椿〔Toona ciliata Roem. var. pubescens(Franch.)Hand.-Mazz.〕和水松〔Glyptostrobus pensilis(Staunt.ex D.Don)K.Koch〕的种子萌发和幼苗生长情况。结果表明,随着NaCl浓度的增加,2个树种的种子萌发率和简化苗木活力指数均明显下降,在0.1%、0.2%、0.4%和0.6%NaCl胁迫条件下,毛红椿和水松种子的最终萌发率分别为89.3%、87.3%、62.7%、32.0%和26.0%、16.7%、6.0%、3.3%,简化苗木活力指数分别为1.39~0.08和1.52~0.07,且毛红椿的种子萌发率和简化苗木活力指数均明显高于水松。萌发恢复实验结果表明,高浓度NaCl处理后的种子具有较高的萌发恢复率。根据实验结果初步判定毛红椿种子具有较强的耐盐性。

Influence of salt stress on germination and seedling growth of two valuable fast-growing tree species

Using 1/2 Hoagland as basic culture solution,the status of seed germination and seedling growth of Toona ciliata Roem.var.pubescens(Franch.) Hand.-Mazz.and Glyptostrobus pensilis(Staunt.ex D.Don) K.Koch were researched under different concentrations of NaC1 stress.The results showed that with increasing of NaCl concentration,both seed germination rate and simplified vigor index of seedling(SVIS) of the two species were decreased gradually.Under 0.1%,0.2%,0.4% and 0.6% NaCl stress,germination rates ofT.ciliata andG.pensilis seeds reached to 89.3%,87.3%,62.7%,32.0% and 26.0%,16.7%,6.0%,3.3% respectively,their SVIS were 1.39-0.08 and 1.52-0.07 respectively.Seeds of T.ciliate showed higher germination rate and SVIS than G.pensilis in all salinity.Recovery experiments showed that recovery rate of germination of the two species seeds treated by higher salinity were higher than that by lower salinity.It is preliminarily concluded that the salt tolerance of T.ciliata seed is higher than that of G.pensilis seed.