【作者】 刘青华；

【导师】 周志春；

【作者基本信息】 中国林业科学研究院 ， 林木遗传育种， 2010， 博士

【摘要】 马尾松分布广,生长快,耐干旱瘠薄,是我国南方山地主要的针叶商品用材树种之一,广泛用于制浆造纸、建筑、松香等,支撑着我国众多的造纸、木材加工、林产化工等产业发展。本文利用种源试验林、无性系育种群体、测交遗传交配设计试验林、初植密度与种源互作试验林和磷肥与种源互作试验林等系统研究马尾松生长、形质和木材密度不同层次的差异和变异模式,揭示了生长、干形和木材基本密度的一般配合力和特殊配合力效应及所受的遗传控制方式,探索了初植密度和施用磷肥对马尾松种源的影响以及与种源间的互作效应,以期为马尾松生长和材性遗传改良及实施高产优质育林措施提供重要科学理论依据。主要研究结果如下:(1)24年生马尾松种源生长、形质和木材基本密度皆存在显著的种源差异,种源胸径、树高和材积生长及树干通直度呈典型的纬向倾群变异模式,这种变异主要是由其产地水热资源条件差异引起的。较之于北部种源,来自南部的种源生产力水平高且树干通直。种源木材基本密度与产地年均温、1月均温、无霜期和≥10℃积温呈显著的负相关。选择生产力高的速生种源可同时改良树干通直度,但会明显降低其木材基本密度。根据种源聚类结果,可将马尾松划分为南部、中部和北部3个种源区,分别筛选出的19个和6个纸浆材和锯材优良种源主要来自马尾松的南部种源区,部分来自中部种源区。(2)各种源除近髓部1～5轮年轮段的木材基本密度外,其它年轮段的年轮宽度和木材基本密度皆存在显著的差异。相对于年轮宽度,不同年轮段木材基本密度的种源变异相对稳定。来自不同种源区的种源年轮宽度的径向变异规律相似,皆表现出先增后减的变化趋势,在6～10轮达到最大值;年轮木材基本密度径向变化规律表现为随年龄增长先增加后逐渐稳定的“S”型变化趋势,并据此筛选出广西横县、恭城、忻城,广东乳源和福建南靖5个木材基本密度径向均匀性高的纸浆材优良种源。早期选择时可在7年生时先淘汰生长较差的种源,在12年生再开展种源生长和木材基本密度的联合选择。(3)23年生马尾松优树无性系生长、形质和木材基本密度皆存在显著的产地间和产地内变异,其中产地内无性系间的变异为产地间变异的1.87～2.38倍。与生长性状比较,木材基本密度在产地间所占的变异分量相对较大。除湖南产地优树无性系年轮宽度从髓心向树皮呈单峰变化外,其它8个产地优树无性系的年轮宽度皆随年龄的增加而逐渐变窄;木材基本密度从髓心至树皮逐渐增大,到达一定年龄后渐趋稳定。除江西、广东和四川产地优树无性系木材基本密度的早期选择年龄晚于径向生长外,马尾松不同产地优树无性系的木材密度和径向生长皆可在5年生时开始早期选择。通过聚类可将180个优树无性系归为3大类和4个亚类。(4)14年生马尾松测交系交配设计测定林中,胸径、树高、木材基本密度和干物质积累量皆存在显著的GCA和SCA效应,其全同胞家系遗传力在0.746～0.908间,受较强的遗传控制,其中胸径、木材基本密度和干物质积累量受加性基因效应控制为主,显性基因效应次之,树高受基因的显性效应控制略高于加性效应,而树干通直度完全由加性基因效应影响。各父本、母本一般配合力效应值因性状而异。依据单株干物质积累量大于总体平均值的20%及树干通直度得分不小于4的选择标准,筛选出7个优良杂交组合,其单株干物质积累量的现实增益和遗传增益分别为22.68%～67.34%和20.25%～60.13%。(5)12年生马尾松种源胸径和枝下高对初植密度反应最为敏感,树高次之,树干通直度和木材基本密度反应最小。广西岑溪、广东信宜、江西崇义和福建武平属于胸径对初植密度敏感的种源,皆表现在2.5 m×2.0 m初植密度下生长量最大,广东高州种源胸径生长对初植密度的敏感性则较小;5个参试种源枝下高皆随着初植密度增加而升高;而树干通直度和木材基本密度的初植密度效应基本不显著。由于参试种源皆为速生丰产的优良种源,初植密度对胸径、枝下高、树干通直度和木材基本密度的种源分化影响不显著,仅树高生长在1.5 m×2.0 m和2.5 m×2.0 m两种初植密度下种源差异明显。统计分析发现,马尾松生长、形质和木材基本密度的种源和初植密度互作效应较小,初植密度不影响种源生长和材质材性的相对表现,综合考虑胸径生长和材质及单位面积生产力等,分别不同培育目标为各种源配置了最适的初植密度。(6)12马尾松不同种源对磷肥的反应差异较大,福建武平属于生长对磷肥不敏感的耐低磷型优良种源,广东高州种源生长的磷肥效果好、持续期长,属磷肥敏感型优良种源,广东信宜、广西岑溪和江西崇义种源对磷肥的生长反应因性状和林龄而有较大的波动。相对于生长性状,马尾松种源树干通直度和木材基本密度受磷肥的影响较小。低磷条件下,福建武平种源较其它种源表现出明显的生长优势,其生长量最大,江西崇义种源的生长表现相对较差;当施用磷肥后,两广种源及江西崇义种源的生长显现不同的肥效,与福建武平种源的生长差异缩小,广西岑溪和广东高州种源的生长量则超过了福建武平种源。木材基本密度和树干通直度在3种磷肥处理下的种源间差异较小,施用磷肥则会明显地提高木材基本密度在种源间和种源内个体间的均匀性。马尾松树高和木材基本密度存在一定的种源×磷肥互作,应依据种源对磷肥反应的特性差异科学施用磷肥。更多还原

【Abstract】 Masson pine (P. massoniana) with better quality of fast growth, wide distribution and strong resistance, is a native tree species in China and has been one of main conifers for afforestation in Southern China and used widely in papermaking, building and rosin. In this thesis, growth and wood quality of masson pine was studied to reveal genetic variation in different variation level, mode of genetic control and response to initial density and phosphorus for growth, stem-form qualities and wood basic density used provenance trail, clonal breeding population, full-sib progeny test of in a testcross mating design, initial stand density by provenance interaction trail and phosphorus by provenance interaction trail, individually. the aim was providing important theories for genetic improvement of growth and wood quality. The results show as follow:(1) There existed significant differences between twenty-four-year-old provenances for growth rate and wood quality. A classical clinal variation pattern responding to the latitude of seed source was found for DBH, height, individual volume and stem straightness, and water and heat resources of seed sources were the main climatic factors which led to the variation pattern. The productivity of southern provenances was higher than that of northern provenances. Strong negative correlation existed between wood basic density and annual mean temperature, temperature in January, frostless season and accumulated temperature over 10℃of the seed source. Genetic correlation suggested that stem straightness could be concurrently improved with the selection of fast-growing provenances, whereas the wood basic density was decreased. The range of Masson Pine in China can be divided into Southern, Middle and Northern provenance zone by cluster analysis. Nineteen and six superior provenances were selected for pulpwood and building timber respectively, most of which were from Southern provenance zone and some from Middle provenance zone.(2) There existed significant differences between provenances for ring width and wood density of every segment except the ring width of 1～5 rings. The variation of wood density was relatively stable with cambial age compared to ring width among provenance and the variation of ring width was easy to be influenced by environment. Pattern for the radial variation of ring width was similar for provenances in difference zones, which increased and then decreased from pith to bark and reached maximum in 6～10 rings. Pattern for the radial variation of wood density was s- type increasing from the pith outward then following by a leveling off period toward the bark. Five superior provenances including of Hengxian GX, Gongcheng GX, Xincheng GX and Ruyuan GD, were selected for pulpwood according to wood density uniformity. The early-late correlation showed, slower growth provenance could be eliminated in 7-year-old, then growth and wood basic density could be combined selection for wood density in 12-year-old.(3) Significant differences existed among seed sources and clones within seed source, and the variation among twenty-three-year-old seed source were 1.87-2.38 time higher than that among clones within seed source. Variance component of seed source for wood density were larger compared growth. Ring width of all seed source was decreasing from the pith to bark excepting Anhui seed source of which was unimodal. Except for Sichuan and Guangdong seed source, pattern for the radial variation of wood density was increasing from the pith outward then following by a leveling off period toward the barks. Early-late correlation showed that radial growth and wood density could be selected in five-year old except the selection for wood density of Jiangxi, Guangdong and Sichuan seed sources was later than radial growth. The 180 clones could be divided into three categories and four subclasses by cluster analysis.(4) Effect was significant differences of general combining ability (GCA) and special combining ability (SCA) for tested trait using the 14-year-old full-sib progeny test. Full-sib family heritability of tested traits under strong genetic control, ranged from 0.746 to 0.908. Additive effects played a more major role than dominance effects for DBH, volume, stem straightness, wood basic density and dry matter accumulation. Height appeared to be almost equally subject to both dominance and additive effects, while stem straightness was controlled completely by additive effect. GCA of parents and SCA varied with either trait or cross combination. Seven cross combinations were selected and could obtain genetic gain of 20.25%～60.13%. (5) Effect of initial stand density was significant on different provenances of 12-year old and traits. DBH and height under branch were most sensitive to initial stand density, effect of initial stand density on height was next and has little effect to stem straightness and wood basic density. DBH of these provenances was sensitive including Cenxi Guangxi, Xinyi Guangdong, Chongyi Jiangxi and Wuping Fujian and grew best under the initial stand density of 2.5 m×2.0 m. Height under living branch of all provenances was significant between different initial stand density and increasing initial stand density resulted in an increase in height under living branch. There also exists significant difference between provenances for height under the initial stand density of 1.5 m×2.0 m and 2.5 m×2.0 m. The study also found provenance by initial stand density interaction on growth, stem-form quality and wood basic density was little and initial stand density did not effect their relative growth performance. Based on comprehensive consideration of growth and wood quality, optimal initial stand density was configured for all provenances according different cultivation objectives.(6) Effect of phosphorus was significant on different provenances12-year old and traits. Wuping FJ was excellent provenance with tolerance of low phosphorus. Gaozhou GD was sensitive to phosphorus and the effect of phosphorus was long duration. Relative to growth, the influence on stem straightness and wood basic density was slight. Wuping FJ was more superior to the other provenances when phosphorus was lack. Provenances from Guangdong, Guangxi and Chongyi JX showed fertilizer efficiency after phosphorus was supplied, in which Cenxi GX and Gaozhou GD even exceed Wuping FJ. The difference of wood basic density and stem straightness was slight between provenances under three phosphorus level. Individual heterogeneity of wood basic density between or within provenances was decreased by phosphorous supply. The experiment also showed that provenance by phosphorus interaction was significant for height and wood basic density,and phosphorous should be supplied according to the effect of provenance to phosphorous.更多还原