山东三个主要赤松(Pinus densiflora Sieb.et Zucc.)种群遗传多样性研究

赤松 (Pinusdensiflora)是山东半岛地带性针叶林的主要建群种 ,由于虫害严重 ,导致种群数量下降 .对山东 3个主要赤松种群的同工酶分析表明 ,种群内基因多样度 (Hs=0 .2 680 )水平较高 ,而种群间基因多样度 (DST=0 .0 0 95)水平较低 .总群体表现为杂合体过度 ,纯合体 (F =-0 .1 2 90 )不足 .种群间基因分化度 (GST=0 .0 3 42 )较低 ,这与赤松种群寿命长、分布连续、风媒异交、种群间基因流 (Nm =7.0 6)较强有关 .虫害是导致赤松种群急剧减少的主要自然因素 ,而人为干扰导致生境片断化 ,也对赤松形成直接威胁 ,因此保护天然赤松种群及其生境对于赤松的持续发展具有重要意义 .

GENETIC DIVERSITY OF PINUS DENSIFLORA SIEB.ET ZUCC.IN SHANDONG PROVINCE

Pinus densiflora an edificator of the zonal coniferous forest on Shandong Peninsula,maintains a high level of gene diversity within populations( H S =0.2680) and a low level of gene diversity among populations ( D ST =0.0095).The species is proved to be excessive in heterozygotes( F =-0.1290) and insufficient in homozygotes.The coefficient of gene differentiation is low( G ST =0.0342),which may be related to the longevity,continuous distribution,anemophily,crossing and strong gene flow ( N m=7.06).Pest insect may be the main natural factor,which caused distinct decrease of P.densiflora population.Habitat fragmentation is a potential threat to the species.So conserving natural populations and their habitats is essential for sustainable development of P.densiflora.