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1.
《林业研究》2017,(5)
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. 相似文献
2.
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. 相似文献
3.
China is one of the countries most severely affected by desertification. Haloxylon ammodendron is an ecologically important component of the desert ecosystem and is one of the main shrub species used for ecological restoration.
We compared the genetic variation in seed and seedling traits among six H. ammodendron provenances arrayed from east to west in China. The experiment was carried out in a greenhouse in well-prepared seedling
beds (lines 1.5 m apart and seeds with in lines 1.0 m apart, 2.0 cm deep) with five lines (seven seeds per line) per provenance
in a randomized block design with six replicates. The seed traits of fruit wing length, kernel weight, germination rate, and
survival rate were compared, as were the seedling traits of internode length, branch number, assimilation shoot diameter,
height, collar diameter, new shoot length, main root number, main root length, aboveground fresh weight, and underground fresh
weight. Moreover, correlations between each seed and seedling trait and climate and geographical factors were assessed. The
results show that the seeds from Dengkou County, Inner Mongolia had the best performance. Germination rate and survival rate
were significantly positively correlated with longitude; and fruit wing length, kernel weight, seedling height, and new shoot
length were significantly negatively correlated with latitude. Fruit wing length was significantly correlated with altitude.
Among the climatic factors, the temperature in January had a strong direct effect on fruit wing length, germination rate,
seedling height, and new shoot length. The mean annual rainfall had a strong direct effect on collar diameter. Humidity had
a strong direct effect on survival rate. Seedling height, aboveground weight, and collar diameter could be important criteria
for early provenance selection in the seedling stage. This study provides a reference for the selection of high-quality H. ammodendron seeds for drylands of northwest China. 相似文献
4.
El Amin Yousif Raddad 《New Forests》2007,34(3):207-222
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. 相似文献
5.
Abraham Loha Mulualem Tigabu Demel Teketay Kenneth Lundkvist Anders Fries 《New Forests》2006,32(1):71-86
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. 相似文献
6.
Catherine Ky-Dembele Mulualem Tigabu Jules Bayala Per Christer Odén 《Agroforestry Systems》2014,88(2):311-320
Within- and between-provenance variations in seed and seedling traits of Khaya senegalensis A. Juss were studied at INERA in Burkina Faso. Nursery grown seedlings from four provenances in Burkina Faso were used for the study. The studies revealed significant variability in all traits evaluated. Seed length and weight significantly varied among provenances and families within provenances, where Bopiel and Koyenga had the highest mean values. Height and root collar diameter of 1 year old seedlings significantly varied among families within provenances. Except leaf biomass ratio and carbon isotope ratio which varied significantly among provenances but not among families within provenances, all other seedling biomass traits—total plant biomass, stem biomass ratio, leaf biomass ratio, root biomass ratio, root shoot ratio, specific leaf area, and leaf area ratio were significantly affected by provenances and families within provenances. The magnitude of variation due to family effect ranged from 65 to 93 % for seed size traits, and from 4.5 to 17.8 % for seedling characters. Estimates of family heritability were moderate to high (0.67–0.95) for seed traits, but low to moderate (0.19–0.59) for seedling characters, indicating that much of the total variation in seed traits is due to the genetic effect. The two most prominent provenances, Koyenga and Bopiel, with higher seed size and greater seedling growth could be considered for an eventual K. senegalensis improvement program in Burkina Faso. 相似文献
7.
[Objective]To compare the differences of seed morphological characters among provinces of Quercus variabilis Bl.,and explore the adaptive growth status of seedlings growing in the central distribution area. [Method]The seeds of 6 Q. variabilis provenances from six provinceswerecollected, and the seedlings were cultivated and transplanted to experimental field in the centre of natural distribution range (Wuhan Jiufeng National Forest Park), then the seed morphology and one-year seedling growth traitswere surveyed. [Result](1)There were significantor extremely significantdifferences among provenances in seed length, seed width, seed length/width ratio and 100-seed mass, the order of seed length among provenances was Beijing Provenance (22.28 mm),Hubei Provenance (22.10 mm), He'nan Provenance (20.80 mm), Shaanxi Provenance (19.57 mm), Yunnan Provenance (18.93 mm)and Liaoning Provenance (18.81 mm), the seed width of Beijing Provenance (19.71 mm) and Hubei Provenance (19.16 mm) was higher than that of the others, the seed length/width ratio of He'nan Provenance (1.38) was extremely significantly higher than that of the others; (2)There were significant or extremely significant differences among provenances in seedling height, ground diameter, leaf number, branching number and seedling height/ground diameter, the Beijing Provenance and Hubei Provenance were better in seedling height and leaf number, which were respectively 19.54 cm and 20.26 cm, 8.32 leaves and 9.50 leaves; (3)A decreasing trend with time for seedling growth traits among provenances was found; (4)There was a positive relationship between seed morphological characters and seedling growth traits except seed length/width ratio; the leaf number was significantly related to ground diameter and branching number and the seedling height and leaf number were closely related to the seed morphological characters; (5)It showed a decreasing trend with the growth time in the relationship between seedling growth traits and 100-seed mass. [Conclusion]The seedlings of Beijing Provenance and Hubei Provenance grew better in the experimental field which might be related to their larger seed mass, and the Yunnan Provenance in the south margin and the Liaoning Provenance in the north margin of distribution area of Q. variabilis grew weaker than the provenances in the centre of distribution area.With the effect of climate change, provenances in the margin of distribution area may lose in the community competition in the seedling stage if it cannot take advantage of its dispersal and settlement and affected by the disadvantage of growth and competition, so that the distribution and population renewal would surely be affected. 相似文献
8.
The extent of genetic variation in seed and seedling traits of Trigonobalanus doichangensis, a rare and endangered tree in southwest China, was evaluated at the population level. Seeds were collected from four natural
populations in the south and southwest Yunnan province, China. Significant differences (P < 0.05) between populations were observed in seed length, seed weight and seedling morphological characters. The analyses
revealed that none of the seed and seedling traits had significant correlations with the geo-climatic variables of the populations.
Among seed and seedling traits, significant correlations (P < 0.05) were discovered among seed length, seed weight and height of 30-day-old seedlings. Significant correlation (r = 1.00, P < 0.01) occurred also between the height and root collar diameter of 4-year-old seedlings. With the exception of seed width
and seed germination percentage, 51–96% of total variation in other seed and seedling related traits was attributed to population
effect, as determined by the broad sense heritability. In conclusion, these observations on variation in seed and seedling
traits should be a reference point, when considering seed collection of this species for ex situ conservation and species
restoration. 相似文献
9.
10.
利用来自7省区36个木荷种源在浙江淳安和福建建瓯两试验点的苗期测定材料,研究其苗木生长、根系特征和叶片形态等12个性状的种源差异及其地理变异模式。方差分析结果显示,除主根长、侧根长和叶片颜色在种源间无显著差异外,其它性状的种源效应都达到显著或极显著水平。种源苗木性状与产地地理气候因子的相关分析发现,苗高、叶片特征(叶片数、叶片宽、叶片厚)及秋末嫩叶颜色等呈典型的纬向变异模式,产地温度则是造成这种纬向变异模式的主要环境作用因子。与北部种源比较,南部种源生长快,叶片数量多,但叶片较薄较窄,其秋末嫩叶颜色变化对寒冷信号反应敏感。影响木荷种子性状表型差异的主导因素是产地的年降水量。以苗高为标准,分别在两地点初选出优良种源10个,它们多来自25°N左右的木荷自然分布区。 相似文献
11.
Alaba E. Gbadamosi 《Journal of Sustainable Forestry》2013,32(4):358-372
Intraspecific variation in useful tree species is a requirement for any improvement program. Fruits of P. nitida were collected from seven different sources along its geographic range in Nigeria; metrical traits of seeds and resulting seedlings were assessed as well as the biomass. There were significant (p ≤ .05) differences in seed metrical traits of length, width, and weight. Seeds from J4 had the highest germination percentage of 95%, while Ore had the lowest percentage of 70. Highest mean values of 2.22 g, 3.11 cm, and 95 for weight, length, and number of seeds per pod, respectively, were obtained from Edo seeds. There were significant (p ≤ .05) differences in seedlings height, collar diameter, number of leaves, internodes, stem dry weight, root dry weight, leaf dry weight, total dry weight, and leaf area among the sources. The highest mean values of 4.33 cm (collar diameter), 2.31 cm (internodes length), were obtained from Edo collection. Other seedling traits and biomass indices were highest in J4 provenance. J4 seedlings had the highest average relative growth rate (RGR) values of 0.0450 gg?1 wk?1 while Etemi seedlings had the highest average net assimilation rate (NAR) value of 0.0063 g2 wk?1. J4 propagule had the best overall performance and is therefore recommended as a seed source for the improvement and conservation of Picralima nitida. 相似文献
12.
利用来自10个省区27个产地的南方红豆杉种子在福建明溪和浙江淳安2个地点开展种源苗期遗传测定,系统研究苗木生长、苗高生长参数、根系特征和干物质积累等性状的种源差异及育苗环境对种源苗木生长的影响.研究结果显示:南方红豆杉苗高、地径和侧枝数存在显著的种源差异.基于苗高生长参数分析表明:种源苗高的增加主要是由于线性生长量、最高生长速率和线性生长速率的提高,而不是由于线性生长期的延长.相对于其它树种,南方红豆杉线性生长速率虽较小,但线性生长期较长.试验虽然未发现根系形态、干物质积累量的种源差异达到统计学上的显著水平,但这些性状的种源绝对值却相差较大,达20%以上.育苗环境对南方红豆杉种源生长影响较大,良好的水热资源和庇荫条件将显著促进苗木的高、径生长.苗木生长性状存在显著的种源与地点互作,但种源与遮阳处理的互作却很小.不同育苗地点南方红豆杉苗高和地径呈现出的地理变异模式是不同的:在福建明溪点,种源苗木高、径生长与产地的地理气候因子相关性较小,苗期速生种源不仅有来自自然分布区偏东部和偏北部的种源,而且还有来自偏南部和偏西部的种源;在浙江淳安点,来自偏东部和偏北部的种源苗高生长量较大,而来自偏南部和偏西部的种源生长则较慢,类似于作者对南方红豆杉有限分布区种源试验的已有研究结果. 相似文献
13.
Early-growth differentiation among seven provenances of Prosopis flexuosa (algarrobo dulce) from the Monte phytogeographic province, Argentina, was studied by comparing their height growth; whole-seedling dry mass gain; allocation to root, stem and leaves; leaf number and leaf area in a common garden. Differentiation among provenances was detected for all the seedling characters examined except leaf number. Family variation within provenances was significant for height growth and leaf number. Variation on the provenance level was related to the elevation, geographic location, and some abiotic conditions of the seed source such as mean annual temperature and frost free period. Latitudinal clines were evident for almost all the growth traits. They were more pronounced for height and aboveground mass, and moderate for total plant mass and leaf area per plant. In addition, a good correspondence in growth traits between young seedlings and older trees of this species (studied by others authors) was also assessed. This fact would permit an early selection and genetic advances in the short term in breeding programs. 相似文献
14.
Differences in seed germination and seedling growth among populations of Pinus yunnanensis Franch. were quantified to provide information for use in the regeneration, reforestation, and improvement of this species. Seed germination and seedling growth traits at the nursery stage were investigated at the population level. We evaluated relationships between pairs of measured traits as well as the association between measured traits and geo-climatic variables including longitude, latitude, elevation, temperature and precipitation. Seedling growth showed significant differences although a low magnitude of variation was found in the seed germination traits among the populations. Some populations with strong and stable growth (e.g., the Baoshan population) may be selected as superior seed sources for regeneration and reforestation. Germination percentage was negatively correlated with elevation, and positively with precipitation. In addition, germination index, vigor index and seedling height were positively correlated with precipitation. Seed germination index, cotyledon number and length, and seedling diameter were significantly and positively correlated with seed weight. Strong correlations between pairs of traits will be helpful in early evaluations for the selection of certain prominent traits. 相似文献
15.
《林业研究》2016,(5)
Differences in seed germination and seedling growth among populations of Pinus yunnanensis Franch.were quantified to provide information for use in the regeneration,reforestation,and improvement of this species.Seed germination and seedling growth traits at the nursery stage were investigated at the population level.We evaluated relationships between pairs of measured traits as well as the association between measured traits and geoclimatic variables including longitude,latitude,elevation,temperature and precipitation.Seedling growth showed significant differences although a low magnitude of variation was found in the seed germination traits among the populations.Some populations with strong and stable growth(e.g.,the Baoshan population) may be selected as superior seed sources for regeneration and reforestation.Germination percentage was negatively correlated with elevation,and positively with precipitation.In addition,germination index,vigor index and seedling height were positively correlated with precipitation.Seed germination index,cotyledon number and length,and seedling diameter were significantly and positively correlated with seed weight.Strong correlations between pairs of traits will be helpful in early evaluations for the selection of certain prominent traits. 相似文献
16.
《Forest Ecology and Management》1997,98(3):209-219
Uapaca kirkiana is a miombo fruit tree with a long history of human use. In Malawi, the species is rapidly gaining attention as an agroforestry tree for fruit production. Accordingly, a formal study to explore variations in fruit, seed and seedling traits within the species was undertaken at the Forestry Research Institute of Malawi. Fruits from 12 natural populations in Malawi were collected in November and December, 1994. Fresh fruit weight and dependent parameters (exocarp, mesocarp and seeds) and seed length, width, thickness and weight (following processing) varied significantly among the populations. When seedlings were raised at Zomba, there were significant differences in germination capacity and height, root collar diameter and biomass production at six months of age. None of these traits was correlated with source latitude, longitude or elevation. Variations in the traits reported emphasize the importance of selecting suitable seed sources before commencing domestication programmes. The levels of variation observed suggest useful gains might be obtained through a breeding programme following careful provenance selection. 相似文献
17.
红锥不同种源苗期生长与变异研究 总被引：1，自引：0，他引：1
对来自福建、广西和广东的5个不同红锥种源成苗物候期和苗木高径生长进行观测。结果表明,苗高和地径的生长节律基本一致,呈现出明显的"慢—快—慢"节律,可将苗期划分为生长初期(4~6月)、生长盛期(7~8月)、生长缓慢期(9~10月)和休眠期(11~12月)4个时期;不同种源间生长差异极显著,苗高和地径的广义遗传力分别为91.48%和86.25%,遗传变异分析初步认定福建华安和广西凭祥的种源表现良好,应作为优良种源重点发展;福建安溪的种源表现中等,有发展潜力,需进一步观测和改良;表现较差的为福建南靖和广东信宜的种源。针对红锥生长节律并结合育苗实践,总结出苗木在各个时期的关键培育及管理技术。 相似文献
18.
对乐东拟单性木兰14个种源种子、苗期以及幼林期生长性状进行了调查分析.结果表明:种子千粒质量、苗高、地径、叶长和叶宽等5个性状在种源间差异极显著;造林保存率种源间差异显著,来自北部的种源,如浙江龙泉种源保存率较高,而来自南部的海南尖峰岭种源保存率较低;幼林期4年生树高、5年生树高和胸径、6年生树高和胸径等5个主要生长性状种源间差异均达到极显著水平,其生长性状广义遗传力为0.855～0.930,说明乐东拟单性木兰幼林期主要生长性状的表型差异主要受遗传因素的控制;乐东拟单性木兰苗高和地径与纬度负相关,表明随种源纬度的升高,乐东拟单性木兰种源苗期生长有减小趋势;乐东拟单性木兰幼林期树高和胸径与经度正相关,与纬度极显著正相关.根据乐东拟单性木兰种源幼林期试验结果,选择出浙江龙泉、福建顺昌和湖南新宁3个优良种源.通过聚类分析,把乐东拟单性木兰种源初步划分为3个区:西部种源区、东部种源区和南部种源区. 相似文献
19.
[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。 相似文献
20.
不同种源无患子苗期生长性状遗传变异研究 总被引：7，自引：0，他引：7
利用9个种源90个家系的无患子(Sapindus mukorossi)种子在浙江省杭州市余杭长乐林场进行苗期试验,结果表明,无患子1年生苗生长期可分为生长初期、速生期和木质化期,地径生长高峰期晚于苗高生长高峰期。方差分析表明,不同种源、不同生长时期苗高和地径生长性状差异较大,呈极显著水平。相关性分析显示,苗高生长性状与种源地纬度呈显著性负相关,南部种源苗期生长性状明显好于北部种源,初步选择出江西上犹、浙江龙泉、江西宜丰3个优良种源,上犹7号、上犹8号、上犹9号、宜丰1号、宜丰6号、龙泉4号和龙泉10号共计7个优良家系。 相似文献