栓皮栎种子及苗期种源变异分析

收集了栓皮栎主要分布区12个种源的种子,对种子及播种苗进行了测定分析.结果表明,栓皮栎种子的大小、质量、发芽率及苗期的生长,在种源间均存在显著差异.栓皮栎中心分布区域种源的种子相对较大,发芽率较高,来自这些区域的种源苗期生长亦较旺盛.苗期生长的显著差异表明,栓皮栎种源间及种源内优良类型选育具有很大潜力.     

大叶榉不同种源早期生长比较

以湖南怀化、浙江湖州、安徽滁州、江苏南京和江西赣州等5个大叶榉种源为材料,比较了大叶榉不同种源苗期及造林早期的生长表现。结果表明:大叶榉苗期和造林早期生长优势明显,显著高于杉木、马尾松和湿地松等速生丰产树种同期生长的行业标准;不同种源间除苗期高生长有显著差异外,造林早期各种源间的生长差异不显著。     

云南松母树林后代苗期生长变异的初步研究

对云南松母树林后代（５个种源８１个家系）苗期生长的分期观测及研究结果表明：云南松苗期生长可分为４个时期，即火柴柱形期（Ⅰ期）、灯笼形期（Ⅱ期）、伞形前期（Ⅲ期）和伞形后期（Ⅳ期）；苗木营养器官的生长发育只有一定的阶段性；种子的大小及发芽率与苗木的生长关系不明显；苗木大多数性状在家系内差异不明显，在家系间和种源间则存在显著的差异；苗期以滇东南和川西南种源的生长量和生物量较大，滇中和滇西种源次之，对照的最小。     

福建永安光皮桦种源家系试验初报

应用采自南方5省区光皮桦(Betula luminiferaH.Winkl.)天然林的12个种源176个家系种子在福建永安进行了苗期测定,并在3个不同海拔高度开展造林试验,调查其1年生幼林的树高、地径,据此对优良种源、家系进行了初步选择。结果表明:光皮桦苗期高生长在种源家系间差异显著;1年生幼林各种源、家系、海拔间树高和地径差异均极显著,种源和海拔的交互作用对树高影响极显著,而对地径影响不显著;种源遗传力高于家系,树高遗传力高于地径;以树高为主要指标,初步筛选出适合当地生长的5个优良种源,并选择出适合不同海拔的优良家系各30个,其种源遗传增益达13.27%,家系遗传增益为12.84%,选择效果良好。     

云南松母树林后代苗期生长变异的初步研究

对云南松母树林后代（５个种源８１个家系）苗期生长的分期观测及研究结果表明：云南松苗期生长可分为４个时期，即火柴柱形期（Ｉ期）、灯笼形期、菜前期和伞形后期；苗木营养器官的生长发育具有一定的阶段性；种子的大小及发芽率与苗木的生长关系不明显；苗木我生状在家系内差异不明显，在家系间和种源间则存在显著的差异；苗期以滇东南和川西南各泊的生长量和生物量较大和滇西种源次之，对照的最上。     

黄山松地理种源苗期试验研究

对黄山松地理种源种子播种品质和育苗试验的研究表明,种源间种子千粒重、室内发芽率、苗圃出苗率均存在显著差异。种源的经度、纬度与千粒重相关不紧密,海拔高与苗高生长量呈较紧密的负相关。各地理种源苗木生长量差异极显著,同一种源不同年份苗木生长量也有差异。浙江省的磐安、东阳、庆源、天台等种源苗期生长较好。     

不同种源山杏种子及苗期变异分析

以19个地理种源当年采集的山杏种子为试材,对其种子形态变异、苗期性状变异及相关性进行分析。结果表明:19个地理种源山杏种子性状和苗期性状均存在极丰富的遗传变异(Sig值均小于0.01),各数量性状种源内变异较小,但种源间变异较大;种子性状种源间变异最大的是杏核百粒重(变异系数为25.02%),苗期性状种源间变异最大的是出苗率(变异系数为48.23%);苗期各性状之间的相关性也有一定的差异,出苗率和保存率的相关性呈极显著(p0.01),苗高、地径和生物量三者两两之间均存在极显著的正相关关系(p0.01,相关系数均达0.95以上)。     

鄂尔多斯高原20个种源文冠果种子发芽特性

为筛选适合鄂尔多斯高原地区的文冠果优良种源,在达拉特旗对20个种源文冠果种子及发芽特性进行试验研究。结果显示:不同种源间和种源内文冠果种子百粒重均存在明显差异,种源内变异系数为3.47%～29.18%,种源间变异系数为15.52%;不同种源文冠果种子发芽率均达到80%以上;发芽势变化范围为18.41%～74.80%,种源间变异系数为35.63%;发芽指数变化范围为16.72～32.49,种源间变异系数18.24%;发芽速度变化范围为3.47～7.01 d,种源间变异系数为20.74%。不同种源的种子发芽率、发芽势、发芽指数及平均发芽速度存在极显著差异(P0.001),说明文冠果不同种源间种子发芽特性已明显分化。通过对文冠果种子发芽特性进行聚类分析,将20个种源文冠果种子至少划分为3类,初步筛选种源地编号为NTB,NTK,NCH,NCK,SYJ的5个种子质量最优种源。研究结果可为文冠果良种选育和优良种源选择提供科学依据。     

文冠果种子及苗期生长性状地理种源变异

[目的]研究不同种源文冠果(Xanthocerassorbifolium Bunge)的种子形态特征及在山东省安丘地区苗期性状差异,了解文冠果不同种源变异特征,为文冠果在山东安丘地区引种和遗传改良提供参考。[方法]以来自山东、河南、内蒙古、辽宁、黑龙江、河北、新疆、陕西等地的27个种源的文冠果种子为研究对象,对其种子形态指标进行测定,并在山东省安丘市开展种源试验。[结果]研究发现:不同种源间文冠果表型性状均存在极显著差异(P0.01),且这些差异可以稳定遗传(遗传力均大于0.9);苗期苗高与种源地降水、年均气温及地径与降水之间呈极显著正相关(P0.01),苗高与种源地纬度、年均日照及地径与年均日照呈极显著负相关(P0.01),种子长、种子宽、种皮厚均与海拔呈极显著负相关(P0.01)。[结论]文冠果表型性状存在丰富的变异,且受较强遗传控制;文冠果苗期性状变异主要受降水、年均气温、年均日照3个环境主导因子的影响,种子性状变异主要受海拔的影响。综合种源苗期生长状况,初步筛选出山东东营、山东安丘、内蒙古库伦、辽宁关山和辽宁海城5个适合安丘地区育苗的速生种源。     

杉木不同优良品种苗期对比研究

在福建省将乐国有林场对不同种源的6个杉木优良品种进行了苗期对比试验。通过对苗高、地径、高径比及苗木质量分级的分析结果表明,参试杉木优良品种播种品质优良,苗木生长良好,质量高;苗高、地径、高径比在各品种苗木间差异达到极显著或显著水平;广西融水杉木种源种子是苗期表现最为优良的杉木品种。     

引进欧洲垂枝桦不同种源苗期选择研究

以引进欧洲垂枝桦不同种源为对象,并以本地白桦种源作为对照,研究引进欧洲垂枝桦不同种源的种子形态特征、发芽特性和在黑河地区的苗期生长表现。结果表明:引进欧洲垂枝桦不同种源在种子长度、种子宽度、种翅长度、种翅宽度、千粒重、发芽率、发芽势、发芽指数、活力指数、苗高、地径、地上生物量、地下生物量和全株生物量存在显著差异,而且引进欧洲垂枝桦不同种源这些指标都显著高于本地白桦对照种源,综合分析表明,引进欧洲垂枝桦新西伯利亚种源在种子形态特征、发芽特性和在黑河地区的苗期生长表现均优,可作为黑河地区欧洲垂枝桦育苗的首选种源。     

Variation in seed traits and seedling vigour of <Emphasis Type="Italic">Cordia africana</Emphasis> Lam. provenances in Ethiopia

Cordia africana is a very important indigenous tree species for timber and other products and services in Ethiopia. Seed traits and seedling vigour of seeds from 12 provenances of the species were compared. Mean seed mass for each provenance was assessed for 1000 seeds in 10 replications, and seed length and width were measured for 100 seeds in four replications per provenance. Germination was assessed in a glasshouse taking 400 seeds from each provenance. Root collar diameter and height of 440 seedlings grown in a nursery for 290 days in Addis Ababa were measured. Seed length, seed width, seed mass, and shoot height and root collar diameter of seedlings showed significant differences (P < 0.001) among provenances. Correlation analysis between seed and seedling traits and environmental variables revealed significant positive correlations between seed width and germination percentage, seed width and altitude, seed width and longitude and seed length and latitude. Negative correlations were obtained between seed width and temperature, seed width and rainfall, seed mass and temperature, and germination and temperature of the seed source. As expected, differences in seed trait did not explain the variability in seedling vigour. Determining quantitative variations in seed traits and seedling vigour among provenances and the patterns along environmental gradients are essential for informing decisions on the tree improvement programme of the species.     

Variation in seed traits and seedling vigour of Cordia africana Lam.provenances in Ethiopia

Cordia africana is a very important indigenous tree species for timber and other products and services in Ethiopia.Seed traits and seedling vigour of seeds from 12 provenances of the species were compared.Mean seed mass for each provenance was assessed for 1000 seeds in10 replications,and seed length and width were measured for 100 seeds in four replications per provenance.Germination was assessed in a glasshouse taking 400 seeds from each provenance.Root collar diameter and height of 440 seedlings grown in a nursery for 290 days in Addis Ababa were measured.Seed length,seed width,seed mass,and shoot height and root collar diameter of seedlings showed significant differences(P0.001) among provenances.Correlation analysis between seed and seedling traits and environmental variables revealed significant positive correlations between seed width and germination percentage,seed width and altitude,seed width and longitude and seed length and latitude.Negative correlations were obtained between seed width and temperature,seed width and rainfall,seed mass and temperature,and germination and temperature of the seed source.As expected,differences in seed trait did not explain the variability in seedling vigour.Determining quantitative variations in seed traits and seedling vigour among provenances and the patterns along environmental gradients are essential for informing decisions on the tree improvement programme of the species.     

Genetic variation in seed and seedling traits in 12 African provenances of Faidherbia albida (del.) A. Chev. at Lodwar, Kenya

The extent of genetic variation in seed length, width, thickness, weight and germination percentage and seedling traits among and within 12 African provenances of Faidherbia albida was examined. The regional provenances showed a consistent variation in seed length, seed width and seed weight: the southern African provenances had the largest seeds and west African provenances the smallest. Seedling height, stem collar diameter and true leaf number differed (P = 0.05) among the provenances 90 days after germination. The seedlings from west Africa were shorter, had smaller stem collar diameter and fewer leaves. In contrast, the southern and east African provenances had taller seedlings with bigger seedling diameter and more leaves per seedling. Seedling traits did not show clear-cut divisions between southern and east African provenances, but the west African provenances formed a distinct group. Positive correlations were found in some of the seed characteristics and seedling height among provenances, which could be an important criterion for early provenance selection. Greater variation was observed for seed and seedling traits among than within provenances suggesting that selection among provenances might result in rapid genetic gain for the traits studied. This revised version was published online in June 2006 with corrections to the Cover Date.     

Ecophysiological and genetic variation in seedling traits and in first-year field performance of eight <Emphasis Type="Italic">Acacia senegal</Emphasis> provenances in the Blue Nile,Sudan

The genetic variation in seed weight, seed number per kg and seedling traits was compared among eight Acacia senegal provenances originating from the clay plain (east) and sand plains (west) of the gum belt in Sudan. The main objective of this study was to identify germplasm sources of A. senegal that have a good seed germination capacity and seedling traits suitable for reforestation in the clay-soil part of the dryland gum belt in the Blue Nile region in Sudan. A specific objective was to tentatively explore the adaptive strategy of A. senegal populations. Seventeen-week-old seedlings were planted in the field at spacing of 3 m × 3 m, giving 100 trees per plot and replication; within a randomized complete block design with four replications. The experimental site was in the clay plain region. Seed variables showed significant differences. Clay plain provenances showed considerable variation in seed weight and seed number. They had the smallest seed weight but the highest seed number, while the sand (western) provenances had the largest seed weight but lowest seed number. Seedling branch number, root length, root to shoot ratio and shoot dry weight differed significantly among the provenances 12 weeks after germination. Clay provenances had the highest branch number and shoot dry weight but the shortest roots and lowest root to shoot ratio. This was interpreted as showing better adaptation to the site in these local provenances in comparison to those originating from the western sandy soil regions. High positive correlations were observed between seedling variables, such as root nodule and branch numbers; this could be used for early selection. The variation was greater between provenance groups than within them, suggesting that especially selection among groups would yield genetic gain.     

欧洲垂枝桦不同种源种子形态及萌发特性研究

以引进俄罗斯欧洲垂枝桦不同种源种子为材料,对不同种源种子形态及其萌发特性进行研究的结果表明:不同种源种子吸水量没有显著差异,而在种长、种宽、种厚、翅长、翅宽、千粒重、含水率、生活力、发芽率、发芽势和发芽指数存在显著差异;新西伯利亚种源种子最大、质量最重、发育最好、有生活力种子高达82.75%;采用混雪冷藏处理种子萌发能力最强,新西伯利亚种源种子发芽率、发芽势、发芽指数分别达到67.63%、55.41%、27.19;而对照种源采用低温冷藏处理种子萌发效果最差,其发芽率、发芽势、发芽指数分别为38.51%、32.42%、11.89。     

秦岭冷杉幼苗适应性的研究

通过对秦岭冷杉不同海拔、光照、苗床类型、覆土深度等条件下的野外播种试验,分析了不同条件下种子萌发、幼苗存活和幼苗生长率的差异,揭示了秦岭冷杉种子及幼苗在天然环境下的适应性.天然生境下秦岭冷杉的平均出苗率只有17.7％,不及实验室发芽率(36％)的一半.海拔、光照、苗床类型、埋藏深度对秦岭冷杉的种子萌发、幼苗存活和幼苗生长率都有不同程度的影响.生产上秦岭冷杉的复壮一定要遵循适地适树的原则.     

Differentiation of seed germination and early seedling growth in ten provenances ofEucalyptus microtheca

An investigation of seed germination and early seedling growth ofEucalyptus microtheca was based on seed collection from 10 widely separated provenances in Australia. Genetic variation of seed germination and early seedling growth was observed among a series of provenances whose natural habitats range from different climatic condition. In the ten provenances, both the model of seed relative germination percentage and the model of seed total germination percentage fitted Logistic regression [y=a/(1+exp(-ex+b))]. In comparison with provenances from four high temperature (mean annual maximum temperature >30.0 °C; mean annual minimum temperature >17.0 °C) areas, six low temperature (mean annual maximum temperature <30.0 °C; mean annual minimum temperature <17.0 °C) areas showed the fast germination rate and the high total germination percentage. For each provenance we have 45 seedlings equally divided into three watering levels (100%, 50%, and 25% of field capacity), and studies on relationship between early seedling growth and climatic factors of the natural habitat of provenance. In control treatment, height growth of the seedling has been associated with intrinsically the driest quarter precipitation in the seed collection areas of provenance. In all the treatments, length growth of the biggest leaf of the seedling was related to mean annual maximum temperature and mean annual minimum temperature in origin of provenance. In contrast, basal diameter growth of the seedling was related to mean annual minimum temperature of the seed collection areas in water stress treatment. From an ecological viewpoint, the fast germination rate and the high total germination percentage of the seed and rapid early growth of the seedling appear to be favourable adaptations to the climatic conditions prevailing in the natural habitat of provenance. Responsible Editor: Chai Ruihai     

Provenance Variation in Seed Morphometric Traits, Germination, and Seedling Growth of Cordia africana Lam

Patterns of genetic variation in Cordia africana, a tropical timber species, were evaluated at the population level. Bulk seed samples were collected from six natural populations in Ethiopia and examined for variations in seed morphometric traits, seed germination, and seedling growth at nursery stage. Analysis of variance revealed significant differences among provenances in all studied attributes except root collar diameter after 4 months of growth. The provenance effect, as determined by broad sense heritability, was 71–98% for seed morphometric traits, 80% for germination capacity, 42% for germination energy, 57–58% for seedling height and 3–13% for root collar diameter. Seed weight showed a significant positive correlation with altitude and negative correlation with mean annual temperature of seed origin. Germination energy was significantly correlated with longitude and mean annual rainfall. Seedling parameters and geo-climatic variables of seed origin were fairly correlated. A significant intercharacter correlation was found between seed length and seed weight, between root collar diameter at the age of 4 months and seed length and weight, as well as between seedling height after 4 and 8 months of growth. It can be concluded that the observed patterns of variation will have implications for genetic resources conservation and tree improvement.