枫香优树扦插育苗关键因子分析

Analysis of Key Factors for Cutting Seedling of Liquidambar formosana

以枫香优树为研究对象,以幼砧连续嫁接方式获取的插穗为繁殖材料,分析了枫香扦插育苗中插穗来源、内源激素、基质组分等几种关键因子的变化。结果表明:嫁接次数对插穗扦插效果影响显著,其中连续嫁接3~4次,生根苗>80%、成活率>90%。随着嫁接次数增加,内源性IAA水平增加、ABA水平降低,GA和ZR水平在嫁接2~3次后明显提升。相关性分析表明:IAA、ABA分别与生根率、成活率呈极显著的正、负相关关系(R^(2)=0.99)。供试4种基质中,以黄泥生根率最高,混合基质(体积比,泥炭土∶珍珠岩∶蛭石=1∶1∶1)成活率与成苗率最高。综合试验研究表明,通过连续幼砧嫁接3~4次,增加生根剂中IAA类生长调节剂浓度,并辅以早期黄泥+后期混合基质为育苗基质,扦插成苗率达90%以上,为今后开展枫香优异种质高效繁育奠定了坚实的基础。

As a famous ornamental tree species,Liquidambar formosana has high medicinal value and good material,and it has become an important silvicultural tree species in southern China at present.It is an effective way to improve the quality of forest stand,speed up the breeding process and promote the development of industry.The cuttings obtained by continuous grafting with young anvil were used as propagation materials.The changes of several key factors such as cuttings source,endogenous hormones and matrix components in cuttings of L.formosana were analyzed.The results showed that the number of grafting times had a significant effect on the cutting effect of cuttings.Among them,continuous grafting for 3~4 times;rooting seedlings is more than 80%and survival rate is more than 90%.With the increase of grafting times,the levels of endogenous IAA increased and ABA decreased,while the levels of GA and ZR increased significantly after 2-3 grafting times.Correlation analysis showed that IAA and ABA were positively and negatively correlated with rooting rate and survival rate,respectively(R^(2)=0.99).Among the four substrates tested,the rooting rate of yellow mud was the highest,and the survival rate and seedling rate of mixed substrates(volume ratio,peat∶perlite∶vermiculite=1∶1∶1)were the highest.The experimental study showed that by increasing the concentration of IAA growth regulator in rooting agent for 3~4 times,and supplemented with the mixed substrate of early yellow mud and later stage as the seedling raising substrate,the seedling formation rate of cutting reached more than 90%,which laid a solid foundation for the efficient breeding of high-quality germplasm of L.formosana in the future.