中国西南几种松树球果鳞片松脂含量对球果延迟开放的影响

目的]探究松树球果延迟开放的机制,讨论松树球果鳞片松脂含量对延迟开放的影响。方法]以云南松、地盘松、细叶云南松、高山松、马尾松和思茅松为研究对象,调查球果宿存年、延迟开放度。采集当年生球果并测定球果鳞片中松脂含量,分析松树球果鳞片松脂含量与延迟开放度的相关性。结果]球果宿存是延迟开放的基础,当球果鳞片松脂含量低于6%时的物种,其球果没有延迟开放现象。在具有延迟开放的云南松种内的3个变种,其球果鳞片松脂的含量与其延迟开放度呈正相关(R^2=0.997,P=0.036),但在种间水平,球果鳞片松脂含量与其延迟开放度并无线性关系(R^2=0.01,P=0.902),推测是由于环境和基因的差异较大所致。结论]球果鳞片松脂含量对球果延迟开放起重要作用,含量过低则没有延迟开放;在具有延迟开放的云南松变种内,球果鳞片松脂含量显著影响其延迟开放程度。

Effect of Resin Content in Cone Scales on Cone Serotiny in Pines in Southwest China

Objective]To investigate the effect of resin content of pine cone scales on serotiny.Method]Cone persistent ages,the degree of serotiny and the resin content of current-year cone scales in six pine species(Pinus yunnanensis Franch.,P.yunnanensis var.pygmaea Hsueh.,P.yunnanensis var.tenuifolia Cheng et Law.,P.densata Mast.,P.massoniana Lamb.,and P.kesiya var.langbianensis Gaussen.)were investigated,and the correlation between resin content of cone scales and the degree of serotiny were analyzed.Result]For the species whose resin content of cone scales less than 6%,the persistence of cones,which is the indication of serotiny,was not observed.In P.yunnanensis varieties characterized by serotiny,the resin content of cone scales was positively related to the degree of serotiny(R^2=0.997,P=0.036).However,the relationship between the cone scale resin content and the degree of serotiny was not significant(R^2=0.01,P=0.902)across these taxa,which may be due to the large genetic and environmental differences.Conclusion]The results indicate that the resin content of cone scales plays an important role in pine serotiny and there will be no serotiny when it is too low.In P.yunnanensis varieties with serotiny,the serotiny degree is effected by the resin content of cone scales.