马尾松种源加密实生种子园子代测定的初步研究

经15年的经营和观测马尾松种源加密实生种子园,摸清并掌握了5大种子区18个种源270个家系的遗传变异特性。为进一步揭示子代的变异,进行了子代苗和子代林的测定研究,结果表明,子代苗在不施肥的情况下,中亚热带15个种源的苗高、地径的生长优势明显,80%～90%达到Ⅰ级标准,而安徽省3个种源(对照)只有40%～50%能达到Ⅰ级标准,差异竟达1倍。6年生子代测定林,其17个种源的平均材积生长量比潜山对照种源增益73.5%,可见生长指标连续稳定变异的优势明显;同时,树干通直度I级木平均达到55.3%,而潜山对照I级木平均为25%,可见形质指标差异极其明显,将为选择改良提供可靠的依据。     

高粱航天诱变后代的观察与分析

选用高粱恢复系体细胞克隆变异后代稳定材料R111,搭载1996年第十七次返回式卫星进行处理,其后代获得大量变异系。经过几年筛选,已获得许多优异新种质资源,表现特殊的有:①成熟期提早15d。②株高降低40cm。③品质变化明显,氨基酸总量比对照增加14.10%,可溶性糖比对照增加25%,单宁降低30%。④获得一批航天诱变新不育系。     

马尾松优树子代材性的初步研究

本文通过对４３个马尾松优树子代１０年生时的材性进行初步分析,结果表明：（１）木材相对密度在家系间存在显著的差异,而纤维素含量则差异不显著;（２）对马尾松材性的选择,除了应利用家系间差异外,还应注重家系内个体间的选择;（３）进行马尾松纸浆材家系选择时,应以生长量为主、材性为辅。     

湖南杉木优良无性系在福建洋口的表现

通过对湖南省优选出的杉木 1 8个无性系子代测定 ,结果表明 :无性系间在树高、胸径和材积生长性状及与环境的交互作用存在极显著差异。无性系间生长快慢差异较大 ,对环境的反应很敏感。无性系群体平均生长量差于我省初级种子园混系子代。因此 ,在选择应用杉木无性系时要谨慎 ,须经本地测定确实优良的无性系才能推广应用     

Provenance and family variation in growth performance of Eucalyptus tereticornis (Sm.) in a provenance cum progeny trial in Midnapore, India

Eucalyptus tereticornis Sm. is an important species for agroforestry and commercial plantations in India. Results of a combined provenance–progeny trial of E. tereticornis laid out in 2002 at Midnapore (West Bengal) located in eastern tropical region of India are reported and discussed. Twelve provenances representing 70 families from Australia and Papua New Guinea were evaluated up to the age of 3 years. As a local seed source open-pollinated seed collected from a land race, i.e., Mysore gum (commonly known as Eucalyptus hybrid) was used to serve as check material (control). Significant variation in plant height, clean stem height, girth at breast height (GBH) and field survival was observed due to provenances, as well as families within provenances. This offers an ample scope to a breeder for increasing the growth and productivity in E. tereticornis through selection of provenances and families having potential for higher productivity. Heritability (narrow sense) values were appreciable for growth traits. Within provenance individual tree heritability estimates for height, clean stem length, GBH and number of branches at age 3 years were 0.318, 0.215, 0.269 and 0.231, respectively (assuming a coefficient of relationship of 0.4 for open-pollinated families of E. tereticornis). Provenance of Walsh River, Queensland Australia performed best for plant height, clean stem height, GBH, number of branches and field survival. Apart from this, the provenance from Oro bay to Emo, Papua New Guinea and Burdekin river, Queensland also showed good performance. Provenance from Yurammie, SF from New South Wales performed poorest for growth and survival. Correlations on growth traits were high and statistically significant, indicating that substantial gains could be achieved through indirect selection for one trait based on the direct selection for another. Age–age genetic correlations between age 1 and 3 years for the growth traits were highly significant and positive. Geographic clinal variation pattern was observed as latitude was negatively correlated with height and GBH (P < 0.05); longitude with number of branches (negative, P < 0.05). Fair differences were observed between phenotypic and genotypic coefficient of variability.     

油松种子园子代变异和遗传稳定性的分析

对70个4年生油松优树子代家系在3个试验点的区域试验分析的结果表明:各试点油松家系间高生长差异均达到极显著水平,其中陇县、黄陵平均生长量大于对照30%以上;3个试验点家系遗传力为0.562～0.783,遗传变异系数为6.938%～9.682%,遗传增益显著;家系×地点的互作效应达到显著水平.根据Eberhart-Russell模式对油松家系进行稳定性分析,结合生长表现将参试家系划分为4种类型,其中高产稳定型家系30个,平均遗传增益在17%以上.     

14年生油松测定林树高生长分析

六十年代以来,国内外许多学者在早期选择方面作过不少的研究,但无统一认识。Cannell认为,在林冠郁闭前,林木处于开放的生长环境,而在林冠郁闭后,处于竞争的生长环境,因此,树高在林冠郁闭前后可能不相关,甚至为负相关;Franklin的看法与此相似。但是,Lambethc在总结了8位学者对花旗松、北美黄松和火炬松等8种针叶树的研究结果后确信,树高生长的早期选择是有效的;叶培忠等对杉木优树子代和产地测定林的研究表明,早晚生长相关是显著的。油松(Pinus tabulaeformis Carr.)是我国北方主要造林树种之一,生长周期较长。本项研究所用材料是我国定植最早的油松测定林,为了供选择优树和早期预测时参考,缩短育种周期,我们将14年来的工作总结如下。     

用AFLP分子标记鉴定冬枣自然授粉实生后代杂种的研究

 应用AFLP技术对65株冬枣自然授粉实生后代进行杂种鉴定, 从81对EcoRⅠ和MseⅠ选择性引物中筛选出12对带型清晰且多态性较高的引物。用这12对引物共扩增出517条谱带, 其中多态性带376条, 多态性百分率为72.7%。共扩增出金丝小枣特征带10条, 鉴定出34株冬枣×金丝小枣杂交实生苗;扩增出尖枣特征带7条, 鉴定出冬枣×尖枣杂交实生苗15株; 不能确定的有16株。     

长白落叶松优树选择效果的评价

利用黑龙江省林口县青山林场长白落叶松自由授粉子代林资料,分析和探讨了优势木、精选树的选择效果及遗传增益,并提出了合理的落叶松育种策略。优势木、中等木、劣等木3个等级的自由授粉子代林树高、胸径和材积等10个性状家系间差异都未达显著水平,亲本与子代性状相关也不显著,说明表型选择效果一般。优势木自由授粉子代树高、材积、冠型、干型等性状遗传力虽处于中低等水平,但优势木材积、树高等性状值仍具有一定优势,在早期缺少结实等数据情况下,还应重视优树选择。15年生时,精选树与优势木相比优势十分明显,树高、胸径和材积分别大4.8%、9.9%和23.2%。由于落叶松生长性状早晚相关显著,应采取能够获得遗传增益较高的1.5代无性系种子园的营建策略来大量生产优良种子。