容器类型和胚根短截对栓皮栎容器苗苗木质量及造林初期效果的影响

摘要

[目的] 容器类型和胚根短截可有效调控苗木质量,同时采用2种措施培育苗木,从苗圃和造林2个阶段探讨对苗木质量的叠加效应,为丰富苗木质量的调控措施提供参考.[方法] 以栓皮栎容器苗为研究对象,将胚根短截(RP)和不短截对照(CK)的种子分别播在2种容器(D40,Slit)中,测定苗圃阶段栓皮栎根系结构、生长、养分浓度和造林效果.[结果] 容器类型和胚根短截的交互作用对根系结构和养分浓度影响显著,D40-CK组合促进<2 mm径级根系发育,并提高根系总表面积和体积,而D40-RP组合有利于提高K浓度,证实2种育苗方式组合研究的必要性.主效应表明,D40容器更加有利于2~5 mm径级根系发育和苗木地上部分的生长,但导致苗木根茎比下降;造林1年后依然促进幼树高和地径生长;造林2年后,促进作用消失.胚根短截抑制>5 mm径级根系发育,并且对苗高、地径和根生物量有负面影响;造林1年后,对幼树高和地径的抑制作用依然存在;造林2年后,胚根短截处理的成活率显著降低,但促进根系生长和养分吸收.[结论] 苗木根系结构、生长、养分和造林初期效果证实采用容器类型和胚根短截组合调控苗木质量的必要性.培育主根发达树种栓皮栎的最佳组合为D40容器和胚根不短截(CK).%[Objective] Container type and radicle pruning have been individually proved to effectively regulate seedling quality.In current study,we examined whether the combination of these two approaches could yield a superior effects on seedling performance during nursery and field phases in order to provide reference for the container seedling cultivation.[Method] Quercus variabilis seeds with the radicle pruned (RP) or control (CK) were sown in two different container type (D40 and Slit).Root architecture,seedling growth,nutrient concentration and subsequent field performance of the seedlings were investigated.[Result] Container type and radicle pruning significantly interacted root architecture and nutrient concentration,the combination of D40-CK improved growth of roots with diameter < 2 mm,and increased total root surface area and volume while the combination of D40-RP increased K concentration,indicating the necessity of combining the two approaches.The main effects indicated that D40 treatment increased growth if roots with diameter for 2-5 mm and aboveground,but decreased R/S in the nursery.The D40 treatment promoted seedling height and RCD growth within the first year after outplanting.However,the promotion disappeared in the second year after outplanting.Radicle pruning treatment decreased growth of roots with diameter > 5 mm,seedling height,RCD and root dry mass of seedlings in the nursery.The pruning treatment still inhibited height and RCD growth of seedlings in the first year after outplanting.Radicle pruning treatment decreased survival but improved root growth and nutrient uptake in the second outplanting season.[Conclusion] Both the interactive and main effects of container type and radicle pruning on root architecture,seedling growth,nutrient status and early field performance indicated that it is necessary to combine the two approaches to improve seedling quality.The optimum combination of D40 container and non-radicle pruning (CK) was recommended for container seedling production of Q.variabilis with a dominant taproot.