共查询到20条相似文献，搜索用时 765 毫秒
1.
Lin Chen Chunsheng Wang Bernard Dell Zhigang Zhao Junjie Guo Daping Xu Jie Zeng 《林业研究》2018,29(1):111-119
Betula alnoides is a fast-growing hardwood species grown in large plantations in Southeast Asia and South China. Nitrogen requirements for producing robust seedlings, growth and nutrient dynamics were investigated using exponential fertilization treatments. Root collar diameter, height, dry mass and nutrient contents of seedlings increased exponentially in all fertilization treatments as time progressed. Moreover, with water soluble fertilizer (Plant Products plus microelements N–P2O5–K2O: 20–20–20), 300 mg N seedling?1 was adequate. Vector analysis revealed that P was the most responsive nutrient element, followed by N and K. Dilutions of N and K were evident in the plants without N addition, which induced initial P sufficiency and then luxury consumption probably due to the antagonistic interaction between N and P. However, deficiencies of N, P and K were mostly observed in all exponential regimes during the experiment because seedling growth rate exceeded nutrient uptake rate, inferring that further study on improving the nutrient uptake efficiency is needed. Analysis of relationships among nutrient supply, dry mass, N content and N concentration demonstrated that 100–400 mg N seedling?1 induced sufficiency to luxury consumption of nitrogen without significant change in dry mass, and 400 mg N seedling?1 is recommended to apply for nutrient loading of seedlings before outplanting. The findings will help improve seedling quality and enhance the production of robust seedlings for plantation forestry of this species. 相似文献
2.
[目的]探讨控释肥和灌溉方式对栓皮栎(Quercus variabilis Bl.)容器苗生长、养分含量、基质电导率(EC)及2年造林效果的影响,为培育高质量苗木提供参考。[方法]以栓皮栎容器苗为研究对象,采用双因素完全随机试验设计,设置5个施肥水平(以N元素含量为基准,5个施肥水平分别为:25、75、125、175、225 mg·株~(-1))和2种灌溉方式(上方喷灌(O)、底部渗灌(S)),测定栓皮栎容器苗形态指标、养分含量、根系生长、基质EC值及连续2年造林效果。[结果]表明:(1)施肥量和灌溉方式二者对苗木形态指标影响存在交互效应,225-O处理的苗木地径、根生物量、单株生物量最大,但根生物量、单株生物量在225-O、125-S、175-O处理之间差异不显著。225-S处理的苗高、茎生物量、茎根比最大,茎生物量在225-S与225-O之间差异不显著。(2)苗木茎、根的氮磷钾浓度和含量随施肥量的增加而增大,施肥量125、175、225 mg·株~(-1)处理之间的根氮、磷含量及单株磷含量差异不显著。(3)增加施肥量促进苗木根系的生长,施肥量为125、175、225 mg·株~(-1)处理之间的根系表面积、体积差异不显著。(4)基质EC值随施肥量的增加而增大,底部渗灌显著提高了基质上层、下层的EC值,基质上层、下层的最大EC值分别为4. 69、0. 56d S·m-1,没有对苗木生长产生不利影响。(5)和上方喷灌相比,底部渗灌显著地促进造林第1年幼树的树高、地径生长;造林第1年、第2年的树高和地径均随施肥量的增加而增大,造林第2年,施肥量125、175、225 mg·株~(-1)处理之间的树高、地径差异不显著。[结论]底部渗灌提高了栓皮栎容器苗体内的养分含量,促进了造林第1年幼树树高、地径的生长。施加控释肥有利于苗期苗木质量的提高及造林后苗木的快速生长。综合考虑苗木质量、经济效益、环境利益,培育栓皮栎容器苗可选择底部渗灌和控释肥量为125 mg·株~(-1)的组合(以N元素含量为基准)。 相似文献
3.
《Scandinavian Journal of Forest Research》2012,27(5):409-414
Second-year Norway spruce seedlings [Picea abies (L.) Karst.] grown in containers were divided into three fertilization levels in August [5, 15 and 25 mg nitrogen (N) seedling?1]. The resulting foliar concentrations of N were 11.0, 13.1 and 15.8 g kg?1, respectively. Seedling height (mean 26.0 cm) did not differ among treatments. The next spring, the seedlings were tested in two experiments. (1) The seedlings were transplanted into pots containing sandy soil in the greenhouse, where they were fertilized with either pure water or nutrient solution (22 mg N l?1). (2) The outplanting performance of the autumn-fertilized seedlings was tested on a sandy field. In the greenhouse experiment, the autumn fertilization level affected height growth and root egress of the seedlings significantly, but less than fertilization with a nutrient solution after planting. In the field experiment, during the first season after transplanting shoot growth of the seedlings increased with the level of autumn fertilization. After the second and third seasons, the seedling stem volume was highest with the highest level of autumn fertilization. These results suggest that, by improving the preplanting nutrient status of seedlings, the growth of shoot, stem diameter and root biomass can be enhanced after planting, especially on nutrient-poor soils. However, heavier autumn fertilization than that used here may yield a greater and more persistent increment in growth. 相似文献
4.
《Forest Ecology and Management》2006,221(1-3):63-71
The growth and development of Pinus pinea seedlings grown in different containers was followed through one growing season in the nursery and 3 years following outplanting in the field. The variables studied in the nursery were height, diameter, biomass of shoots and roots, nutrient uptake and root density. The measured field variables, height and diameter increment and survival, were correlated with the nursery variables. Container volume had the greatest influence on plant morphology. Containers with larger rooting volume had seedlings with larger height and diameter, greater nutrient content, and better field performance. Growing density was correlated with seedling morphology and nutrient concentration in the nursery. Among the variables that influenced container volume, the diameter of the container was the most important, while the depth of the container had a minor influence on seedling morphology.The best indicator of seedling development in the nursery was the ratio of container depth to container diameter, and the optimum ratio was 4. All containers produced seedlings with some root spiralling, including those containers with ribs. There was no relationship between either the number of spiralling roots or the angle of spiralling and container characteristics. Furthermore, root spiralling did not influence seedling performance following outplanting. Root density (root biomass/cm3) was inversely correlated with container volume but there was no correlation with either depth or growing density. The largest plants were produced with container volumes of 300–400 cm3, depth/diameter ratios of 4, and growing densities of 200–300 seedlings/m2. These growing conditions will result in larger Pinus pinea seedlings coming out of the nursery, which will increase growth following outplanting. 相似文献
5.
Exponential nutrient loading: a new fertilization technique to improve seedling performance on competitive sites 总被引：10，自引：1，他引：10
Reforestation efforts in Ontario have become increasingly more reliant on containerized planting stock since these seedlings are less costly to produce and plant than bare-root stock. Container seedlings, however, tend to be more susceptible to competing vegetation when planted on weed-prone sites often requiring release by chemical herbicides. We have developed cultural techniques to improve the competitiveness of containerized seedlings by promoting initial outplanting performance thus reducing the need for early vegetation control. The approach is based on two new preconditioning practices, exponential fertilization and nutrient loading, which induce a steady-state build up of nutrient reserves in seedlings for outplanting. Exponential nutrient loading integrates these practices with high dose fertilization inducing luxury consumption. Steady-state culture corresponds better with the competitive outplanting environment, since stable internal nutrient accumulation in the greenhouse phase conforms with steady-state nutrient uptake of natural exponentially growing vegetation in the field, and exponential nutrient delivery to container-restricted root systems also better simulates nutrient flux reached by expanding roots in a field soil with constant nutrient availability. Combined with nutrient loading, the higher nutrient reserves and improved nutrient balance in seedlings contribute to enhanced stress resistance and increased growth performance. This paper reviews the theory and practice of exponential nutrient loading during seedling culture, presents results of growth and nutritional responses of seedlings planted on competitive sites, and suggests appropriate criteria for quality testing of nutrient loaded stock. 相似文献
6.
Early establishment of seedlings in reclaimed oil sand areas is often limited by low nutrient and water availability due to factors such as strong understory vegetation competition. Management practices such as nursery fertilization and field weed control could help early establishment of planted seedlings and reclamation success. We investigated the effect of nursery nutrient loading and field weed control on the growth, nitrogen (N) retranslocation within seedling components, and plant N uptake from the soil for white spruce (Picea glauca [Moench] Voss) seedlings planted on a highly competitive reclaimed oil sands site for two years. Exponential fertilization during nursery production increased the root biomass but not the nutrient reserve in the seedling. In the field experiment, on average across the treatments, 78 and 49% of the total N demand of new tissue growth in the first and second year were met by N retranslocation, respectively. Though exponential fertilization did not affect N retranslocation, it increased the percent height and root collar diameter growth. Weed control increased not only the growth of seedlings by increasing soil N availability, but also N retranslocation within the seedlings in the second year after outplanting. We conclude that vegetation management by weed control is feasible in improving the early growth of white spruce seedlings planted on reclaimed soils and facilitate tree establishment in the oil sands region. Optimization of the nursery exponential N fertilization regime for white spruce may further help with early revegetation of reclaimed oil sands sites. 相似文献
7.
The biomass and ratio of root-shoot ofPinus sylvestriformis seedlings at CO2 concentration of 700 μL·L−1 and 500 μL·L−1 were measured using open-top chambers (OTCs) in Changbai Mountain during Jun. to Oct. in 1999. The results showed that doubling
CO2 concentration was benefit to seedling growth of the species (500 μL·L−1 was better than 700 μL·L−1) and the biomass production was increased in both above-ground and underground parts of seedlings. Carbon transformation
to roots was evident as rising of CO2 concentration.
This project is supported by Chinese Academy of Sciences
Responsible editor: Chai Ruihai 相似文献
8.
9.
Current policy in Ireland calls for increased quality and quantity of broadleaved seedling plantings. Simultaneously, concerns
regarding environmental contamination necessitate development of nursery production methods that minimize impacts. Exponential
(E) fertilization has potential for producing high-quality seedlings through nutrient loading, while simultaneously minimizing
nitrogen (N) losses during culture. We investigated the effects of a wide range (0.10–1.0 g N seedling−1 year−1) of E fertilization rates on seedling morphology and nutrition of Quercus robur L., as well as soil N status and N budget during one growing season in a bareroot nursery in County Carlow, Ireland. The
N budget showed significant N losses, especially in the highest fertilizer treatments, due to high precipitation. Seedlings
receiving the 0.5 E rate were morphologically and nutritionally superior to all other treatments. Results indicate that it
may be possible to produce 1-0 bareroot seedlings meeting target specifications in Ireland and other countries of similar
climate and soils if further manipulations to seedling culture are implemented; however, potential environmental degradation
via N leaching must be considered when N loading in wet years. 相似文献
10.
Grass interference limits resource availability and reduces growth of juvenile red pine in the field
The effects of competing grasses on resource availability, growth and ecophysiological characteristics of 3-0 red pine (Pinus resinosa Ait.) seedlings were examined the first two years following outplanting in Anoka County, Minnesota, USA. Equal numbers of seedlings were planted into suppressed and undisturbed grass communities in a sandy soil. Grass suppression was maintained throughout the first growing season, but partially discontinued thereafter on the site. During the first field season interference from grass reduced pine seedling root collar diameter, needle length, number of new root tips, and lateral root length by over 40%. Mean pre-dawn needle water potential was 0.55 MPa lower in undisturbed grass plots during a brief drought in year one, but otherwise water stress was not significantly (p=0.05) influenced by grass interference. The presence of grass also reduced, up to 50%, the photosynthetically active radiation reaching the seedling canopy. At the end of year one, total biomass N, P, K, and Ca content were significantly (p=0.05) less in seedlings growing in the undisturbed grass community. Nitrogen was deficient in seedlings growing in grass. After two growing seasons, seedling shoot length (p=0.03), root collar diameter (p=0.001), and needle length (p=0.001) were significantly less (40, 54 and 20%, respectively) for seedlings growing in undisturbed grass. Seedling growth reductions induced by grass competition were associated with multiple environmental stressors in the field and not restricted to water stress as was observed in earlier studies with pine species at low and mid-latitude sites. 相似文献
11.
Guolei Li Yan Zhu Yong Liu Jiaxi Wang Jiajia Liu R. Kasten Dumroese 《European Journal of Forest Research》2014,133(6):983-992
Maintaining proper seedling nitrogen status is important for outplanting success. Fall fertilization of evergreen conifer seedlings is a well-known technique for averting nitrogen (N) dilution caused by continued seedling growth during hardening. For deciduous seedlings, this technique is much less understood, and regardless of foliage type, the interaction of N status prior to fall fertilization and the rate of fall fertilization have yet to be fully explored. Therefore, we fertilized Quercus variabilis container seedlings with either 25, 100, or 150 mg total N seedling?1, applied exponentially, during a 23-week pre-hardening regime, followed by either 0, 12, or 24 mg total N seedling?1 applied during hardening (i.e., fall fertilization) in equal aliquots for 4 weeks. For seedlings without supplemental N during hardening, N concentration in stems and roots increased significantly despite substantial growth. The absence of N dilution was attributed to N translocation from foliage to these tissues, which was independent of pre-hardening N status. Overall, 32 % of foliar N was translocated and accounted for 75 % of the total N increase in stems and roots. Final stem N status was a function of pre-hardening fertilization, whereas root N concentration was affected by the interaction of pre-hardening and fall fertilization. Roots appear to be the main site of N storage, and root N content was significantly affected by pre-hardening and fall fertilization, but not their interaction. A combination of pre-hardening and fall fertilizer at a rate of 100 and 24 mg total N seedling?1, respectively, yielded seedlings with the largest root systems. 相似文献
12.
For establishment to be successful, planted oak must emerge above vegetative competition and browse level. A 3 year study
was established in 2000 in a cutover bottomland hardwood forest in west Alabama to examine the influences of seedling browse
protection and fertilizer use on growth of Nuttall oak (Quercus nuttallii Palm.) seedlings. The treatments included: control, 1.2 m tall wire tree shelter, and 1.2 m tall plastic tree shelter. Fertilizer
(20–10–5) was applied to one-half of all seedlings at planting. Competing vegetation was controlled around all seedlings with
mulch mats and herbicide. Fertilization did not affect height growth or successful establishment after 3 years. Four percent
of protected seedlings (plastic and wire tree shelters combined) were browsed compared to 95% of control seedlings. After
3 years, plastic tree shelters were the most effective treatment for promoting height growth and successful seedling establishment
of Nuttal oak seedlings (193 cm, 92.71% compared to 120 cm, 68.75% and 52 cm, 8.33% for wire tree shelter, and control seedlings,
respectively). Animal browse protection is deemed essential for successful seedling establishment in southern bottomland forests
where deer density is high (density estimated at 27 km−2 in vicinity of study area). 相似文献
13.
采用金佛山方竹母竹分株单株蔸苗、1年生营养袋实生苗、1年生实生裸根苗造林,对造林后竹苗的地径生长、苗高生长、新发苗(笋)数量进行对比研究。结果表明,不同类型苗木对苗木地径生长、苗高生长、新发苗数量均有显著影响。对苗木地径生长的影响为：母竹分株苗造林>裸根苗造林>营养袋苗造林;对苗高生长的影响为：母竹分株苗造林>裸根苗造林>营养袋苗造林;对新发苗(笋)数量的影响为：营养袋苗造林>裸根苗造林>母竹分株苗造林。 相似文献
14.
Acevedo Manuel Álvarez Carolina Cartes Eduardo Dumroese R. Kasten González Marta 《New Forests》2020,51(1):159-174
Ruil (Nothofagus alessandrii) is an endangered keystone species from the Mediterranean climate zone of Chile. Ruil’s fragile state of conservation urges development of restoration programs, but specific protocols for nursery production and field establishment that ensure plant survival are largely unknown. Therefore, we examined the effect on nitrogen (N) fertilization and container size during nursery production in combination with the use of mesh shelters after outplanting on survival and growth during the first growing season in the field. First year outplanting survival of nursery-grown container seedlings was enhanced when seedlings were given nitrogen (N) during nursery production and deployed with mesh tree shelters in the field. The volume of the container had no effect on outplanting survival and growth. Increasing N from zero to 200 mg N L?1 provided sufficient N levels, resulting in increased seedling height, root-collar diameter, shoot biomass, and total seedling N and phosphorous concentrations. Additional N provided by the 400 and 600 mg N L?1 treatments underwent luxury consumption by the seedlings with no further benefits in field performance. Improved growth in the nursery, along with the use of mesh tree shelters after outplanting, especially during the typical summer drought, may be responsible for increased survival during the first growing season. Increasing the performance of nursery-grown ruil seedlings is essential to restoring this endangered, vulnerable, and foundation species within the highly biodiverse, yet seriously threatened endemic Maulino Costero Forest of the Mediterranean climate of central Chile.
相似文献15.
The cutting seedlings ofLiriodendron chinense xtulipifera were treated with the different concentrations of auxin (treatment1: IBA of 50 g·kg−1+NAA of 300 g·kg−1; treatment2; IBA of 100 g·kg−1+NAA of 300 g·kg−1). The biomass nutrient element contents for different organs (root, stem, leaf) of cutting seedling ofLiriodendron chinense xtulipifera were measured by the dry method, Kjeldahl method and Atomic Absorption Spectroscopy method. The result showed that the biomass
of root, stem, and leaf of the cutting seedling treated with auxin was all remarkably increased. The contents of element C
in root, stem and leaf had no significant difference between the control and auxin treatments, while the contents of N, P,
K and Ca in stem were much lower than that in leaf and root. Variance analysis showed that for the same organ with different
concentration treatment of auxin, the four nutrient elements (N, P, K, and Ca) had no significant difference in contents,
while there existed significant or very significant difference in contents of the four nutrient elements in different organs
with the same concentration auxin treatment. The N, P, K and Ca contents were very low in cutting seedlings; as a result,
additional fertilizer should be applied to the seedlings when they were planted in the field.
Foundation item: This paper was supported by Jiangsu Province Science Foundation (BE96350).
Biography: ZHANG Xiao-ping, (1972-), female, Ph. Doctor in Nanjing Forestry University. Nanjing 210037, P. R. China.
Responsible editor: Zhu Hong 相似文献
16.
Juan A. Oliet María Tejada K. Francis Salifu Aleyda Collazos Douglass F. Jacobs 《European Journal of Forest Research》2009,128(3):253-263
Holm oak (Quercus ilex L.) seedlings were exponentially (E) nutrient loaded using incremental increases in fertilizer addition or conventionally
(C) fertilized using a constant fertilizer rate during nursery culture. The fertility treatments (mg N plant−1) were control (0), 25E, 100E, and 100C. Subsequently, 1-year-old plants were transplanted under simulated soil fertility
gradients in a greenhouse to evaluate effects of nutrient loading and post-transplant fertility on seedling performance. Post-transplant
fertility consisted of fertilizing plants at two rates (0 vs. 200 mg N plant−1). A water-soluble fertilizer 20-20-20 was supplied in both nursery and post-transplant experiments. Nutrient loading increased
plant N content by 73% in 100E and by 75% in 100C relative to controls, although no significant differences were detected
between constant and exponential fertilization regimes at the 100 mg N plant−1 rate. When transplanted, nutrient loading promoted post-transplant root growth relative to shoot, implicating potential to
confer competitive advantage to loaded holm oak seedlings after trans-planting. In contrast, post-transplant fertility increased
new shoot dry mass by 140% as well as N, P and K content relative to controls. Results suggest that holm oak seedlings can
be successfully nutrient loaded in the nursery at higher fertility rates, improving its potential to extend new roots, but
alternative fertilization regimes and schedules that better fit nutrient availability to the growth rhythm and conservative
strategy of this species must be tested. 相似文献
17.
容器苗作为高效的育苗措施,可以显著地提高造林成活率。相对于1年生容器苗生长较弱、造林效果差的状况,2年生容器苗可改善造林效果。因此,针对南方红豆杉、浙江楠和浙江樟3种珍贵树种2年生大规格优质容器苗的培育需求,系统研究了缓释肥加载量对其生长、根系发育、生物量积累和分配以及N、P养分积累的影响。结果表明:(1)缓释肥加载量为1.5 kg·m-3时南方红豆杉地径达到最大值,2.5 kg·m-3缓释肥加载量能有效促进浙江樟苗高增长。缓释肥加载对南方红豆杉根、叶和总生物量积累具有显著影响;(2)南方红豆杉和浙江樟总根长、根体积和根系表面积均在3.5 kg·m-3缓释肥加载量下达到最大,而2.5 kg·m-3缓释肥加载量则可满足浙江楠根体积和根表面积的增长;(3)3.5 kg·m-3缓释肥加载量有助于3个树种2年生容器苗养分库中N素的积累,但较低缓释肥加载量(1.5 kg·m-3)利于浙江楠P素养分库的构建。养分含量的提高在一定范围内可促进容器苗生长和养分库中养分的积累,而养分含量过高不仅抑制容器苗生长,还会引起养分在苗木体内的再分配。综合考虑,建议对南方红豆杉和浙江樟2年生容器苗采用1.67 g·株-1 N素和0.74 g·株-1 P素的施肥水平进行培育,而培育浙江楠2年生容器苗宜采用1.67 g·株-1 N素和0.32 g·株-1 P素施肥水平。 相似文献
18.
[目的]研究缓释肥N/P养分配比及加载量对南方红豆杉、浙江楠和浙江樟苗木生长发育的影响,以科学指导大规格容器苗的高效培育。[方法]试验采用析因设计,研究N/P养分配比(1.75∶1、2.25∶1、2.75∶1和3.25∶1)及其加载量(1.5 kg·m~(-3)、2.5 kg·m~(-3)、3.5 kg·m~(-3)和4.5 kg·m~(-3))对3种珍贵树种2年生容器苗生长、株高生长节律、干物质积累及叶片SPAD值等影响。[结果]缓释肥N/P养分配比及加载量对3个树种容器苗生长及SPAD值影响不一。南方红豆杉、浙江楠和浙江樟干物质积累及根冠比在不同N/P养分配比间差异不大,浙江樟苗木生长受N/P养分配比影响较小,随着N/P养分配比增加,明显促进了浙江楠容器苗生长,却抑制了南方红豆杉的生长。缓释肥加载量对3个树种2年生容器苗生长和干物质积累的影响均达到极显著水平,随着缓释肥加载量增加可明显地促进3种树种株高、地径生长及干物质积累,增加了浙江楠地上干物质积累及南方红豆杉地下干物质积累,而对浙江樟根冠比影响未达统计学显著水平,但均显示加载量在3.5 kg·m~(-3)时达到最大值。N/P养分配比及与加载量的互作对3个树种苗木生长和干物质积累影响不明显,说明N/P养分配比对3个树种容器苗生长和质量的影响不因加载量的改变而变化或变化不大,反之亦然。随着缓释肥N/P养分配比的增加,可明显地延长南方红豆杉苗木株高的线性生长期,提高浙江楠株高的线性生长量,但对浙江樟株高的线性生长影响不明显。3种树种苗木叶片SPAD值差异很大,N/P养分配比及加载量并未改变3种树种叶片SPAD值动态变化规律,但随着N/P养分配比提高使南方红豆杉和浙江樟叶片SPAD值的起伏强度增大,3个树种SPAD值动态变化均随加载量增加而增大。[结论]南方红豆杉大规格容器苗培育较适宜的N/P养分配比为A1(1.75∶1)或A2(2.25∶1),而浙江楠和浙江樟为A3(2.75∶1),加载较高量的缓释肥F3(3.5 kg·m~(-3))可明显促进3种树种大规格容器苗的生长及SPAD值的提高,但加载量超过一定限度后,反而影响苗木的生长发育。 相似文献
19.
[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
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设置0、50、100、150、200、300、400、600 mg·株-1 8个N处理,通过盆栽试验研究氮素对闽楠苗生长及光合特性的影响.结果表明:随着供氮量的增加,闽楠苗高、地径、叶面积和根、茎、叶及整株生物量均呈现先增加后降低的趋势,其中,苗高、地径和叶面积均在供氮量100 mg·株-1时最高,而各器官生物量及整株生物量均在供氮量150 mg·株-1时最大;根冠比则随着供氮量的增加呈现单调递减趋势;闽楠苗光合特性与生长表现是契合的,随供氮水平的提高,闽楠苗叶绿素a、b及总量先升高后降低,净光合速率、气孔导度、胞间二氧化碳浓度和蒸腾速率值也均呈先仰后抑之势,恰在供氮量100 mg·株-1时,以上光合参数值均达最高,且不同氮素处理间闽楠光合气体交换参数和蒸腾速率差异均显著.综合闽楠苗各生长及光合指标的分析结果,100～150 mg·株-1的供氮量为闽楠苗温室培育的适宜范围. 相似文献