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1.
国外容器苗质量调控技术研究进展   总被引:3,自引:0,他引:3  
李国雷  刘勇  祝燕  蒋乐  史文辉 《林业科学》2012,48(8):135-142
近年来,由于造林重点由宜林地向困难立地转移,对苗木质量的要求也随之增高.文章系统总结近年来国外容器苗的质量调控技术及其对于我国困难立地植被恢复的重要意义,从指数施肥、秋季施肥、底部灌溉、短日照处理和夏季造林、修根技术、容器规格、冻藏和解冻等研究进展进行了论述总结.指数施肥的每次施肥量与植物生长节律和养分需求同步,施肥效果较优.秋季施肥能避免苗木的养分稀释效应,已被应用于很多树种.实施底部灌溉的植物生长不亚于上部灌溉的植物,而底部灌溉用水量少,氮肥淋溶小.夏季造林时,将正处于速生期的苗木进行短日照处理,诱导顶芽形成,促进根系发育,能提高苗木抗性和造林效果.苗木冻藏可使空气中自由态的水凝固成结晶态的冰,苗木感染病菌几率降低,因此冻藏成为针叶树种贮藏的标准方法.在当前研究热点的基础上,论文就未来研究方向进行展望.  相似文献   

2.
苗木质量是提高造林成活率的基础,它包括苗木的水分状况、木质化程度、根系、苗干损伤、高径比等,这些因素对造林成活率影响很大。苗木的质量主要体现在苗木的规格上,因此造林苗木一定要达到所要求的规格,否则就会影响造林成活率[1]。为了研究黄土  相似文献   

3.
【目的】容器类型和胚根短截可有效调控苗木质量,同时采用2种措施培育苗木,从苗圃和造林2个阶段探讨对苗木质量的叠加效应,为丰富苗木质量的调控措施提供参考。【方法】以栓皮栎容器苗为研究对象,将胚根短截(RP)和不短截对照(CK)的种子分别播在2种容器(D40,Slit)中,测定苗圃阶段栓皮栎根系结构、生长、养分浓度和造林效果。【结果】容器类型和胚根短截的交互作用对根系结构和养分浓度影响显著,D40-CK组合促进2 mm径级根系发育,并提高根系总表面积和体积,而D40-RP组合有利于提高K浓度,证实2种育苗方式组合研究的必要性。主效应表明,D40容器更加有利于2~5 mm径级根系发育和苗木地上部分的生长,但导致苗木根茎比下降;造林1年后依然促进幼树高和地径生长;造林2年后,促进作用消失。胚根短截抑制5 mm径级根系发育,并且对苗高、地径和根生物量有负面影响;造林1年后,对幼树高和地径的抑制作用依然存在;造林2年后,胚根短截处理的成活率显著降低,但促进根系生长和养分吸收。【结论】苗木根系结构、生长、养分和造林初期效果证实采用容器类型和胚根短截组合调控苗木质量的必要性。培育主根发达树种栓皮栎的最佳组合为D40容器和胚根不短截(CK)。  相似文献   

4.
钾肥对文冠果苗木生长的影响   总被引:1,自引:0,他引:1  
文冠果(Xanthoceras sorbifolia Bunge.)育苗中,由于苗木生长迅速,常造成木质化不良,严重影响了苗木及造林质量。通过施用钾肥试验,以促进苗木生长和提高木质化程度。试验结果表明:施用钾肥在10g/m2是比较合理的,既能促进文冠果苗木生长和提高木质化程度,又能达到经济施肥的目的。  相似文献   

5.
意杨、水杉造林后,如遇持续干旱影响成活率,则应及时地给予补植.夏季补植意杨、水杉,由于起苗时不易带土球,且根系不发达,栽活难度较大.同时,意杨造林要求用2年生平茬苗,但夏季这类苗木高度仅2米左右,木质化程度低,加之时值盛夏,有时还会碰到长时间的高温无雨天气,管护措施很难全部跟上,造林质量难以保证.  相似文献   

6.
苗木质量的生理学检验方法王淼,陶大立,劳赞新(中国科学院沈阳应用生态研究所110015)(内蒙古自治区图强林业局)苗木是造林的物质基础,苗木质量的优劣对造林成败影响较大。苗木质量通常因苗高、地径、苗木成熟度(顶芽饱满程度及枝条的木质化、木栓化程度)及...  相似文献   

7.
提高苗木栽植成活率的几项措施   总被引:1,自引:0,他引:1  
为增强造林苗木的抗逆性,提高造林成活率,保护和处理好苗木已成为保证造林质量的重要措施之一。所谓保护好苗木,就是要让苗木不受风吹日晒和人为的机械损伤等,而其中最重要的是要保护好苗木的根系。因为根系的好坏和完整程度,直接影响到苗木生活力的强弱,是决定造林成活率的主要因素;而处理好苗木,  相似文献   

8.
在马尾松育苗过程中应用不同浓度的多效唑进行叶面喷洒试验表明,在苗高20cm左右,间隔15d进行连续2次的叶面喷洒,1000、1500、2000mg/kg浓度能很好地提高苗木质量、抗寒能力和造林成活率,500mg/kg浓度处理效果不明显。3种浓度处理苗木的高径比能控制在较为理想的65左右,侧根数和干物质积累显著增加,木质化程度提高,抗寒能力显著加强,冻害率下降35%,次年造林成活率提高11%,但2000mg/kg浓度处理对次年的新梢生长有一定的影响。  相似文献   

9.
<正> 落叶松全光育苗是一种省工、省料、省钱的方法,约可降低苗木总生产成本的1/3。而且,苗木在全光条件下,生长矮、粗、壮,根系发达,木质化程度高,干物质重量大,质量大大优于遮荫苗木,有利于提高造林成活率。 但是,落叶松全光育苗中午浇降温水,  相似文献   

10.
多效抗旱驱鼠剂在飞播造林中的应用研究   总被引:5,自引:0,他引:5       下载免费PDF全文
用多效抗旱驱鼠剂 (RPA)对飞播用油松、侧柏种子进行拌种处理 ,室内外做发芽及生长试验。结果表明 ,室内RPA的 3个浓度处理油松发芽率比对照提高 13.9%  2 9.8% ,侧柏发芽率提高 2 4 .6 %  2 7.0 % ;油松高生长比对照提高了 9.0 %  19.4 % ,侧柏提高了 2 9.4 %  5 8.8% ,油松成苗率比对照提高 18.5 %  36 .0 % ,侧柏提高了 2 4 .0 %  2 7.5 %。在促进成苗率的同时也促进了苗木根系的生长 ,RPA使油松根系生长比对照提高了 34.6 %  5 0 .0 % ,侧柏根系生长提高了 13.9%  36 .1%。在飞播上应用 ,RPA处理区有苗样方率远远高于对照区 ,处理区苗木分布比较均匀 ,从保存的株数看 ,对照区仅为 0 .0 7株·m- 2 ,而处理区高达 0 .5  0 .8株·m- 2 ;对照区苗木平均高 2  3cm ,处理区为 3  5cm。充分说明多效抗旱驱鼠剂在苗圃育苗或飞播造林中应用 ,能够提高成苗率 ,促进苗木木质化程度 ,使苗木安全越冬 ,促进苗木根系的生长 ,起到以根提水 ,以水促长的作用  相似文献   

11.
Short-day treatment has been used for some conifer species to improve planting stock quality. The aim of this paper was to study the effect of short-day treatment on performance and quality of young seedlings of Italian cypress (Cupressus sempervirens L.), a conifer species abundant in the Mediterranean area. Seeds of Italian cypress were sown in mini-plug cavities. After 5 weeks of growth, seedlings were subjected to four different photoperiods: (a) 14 h (control), (b) 8 h, (c) 6 h, and (d) 4 h for a period of 1–3 weeks, before they were transplanted to bigger size containers. Reducing photoperiod did not result in bud formation or shoot inhibition although it increased the number of lateral shoots. Seedlings subjected to 6-h photoperiod for 2 weeks during pre-cultivation in mini-plugs had improved root characteristics, giving them a higher potential for outplanting success, especially in Mediterranean areas.  相似文献   

12.
Western red cedar (Thuja plicata Donn) seedlings were grown in a greenhouse and subjected to six nursery cultural treatments (long-day wet (LDW), long-day moderate (LDM), long-day dry (LDD), short-day wet (SDW), short-day moderate (SDM), and short-day dry (SDD)) during mid-summer. Seedling attributes were measured before fall and spring planting.Short-day and moisture stress treatments reduced shoot but not root growth, resulting in reduced shoot to root ratios. Fall tested LDW seedlings had a higher osmotic potential at saturation and turgor loss point than other treatments. Fall tested short-day seedlings had lower resistance to plant water movement. The LDW seedlings had the greatest new root growth in fall testing, while one of the lowest in spring testing. In the fall, LDW seedlings had the greatest net photosynthesis (Pn) at 25 °C root temperature, with all treatments having a similar decline in Pn as root temperatures decreased to 1 °C. In the spring, all treatments had a similar decline in Pn with decreasing predawn shoot water potential. Moisture stress and short-day nursery cultural treatments applied in mid-summer will not harden western red cedar seedlings for all potential field conditions.Spring, compared to fall, tested seedlings had two times the shoot and three times the root dry weight. Spring tested seedlings had a lower osmotic potential, maximum modulus of elasticity, relative water content at turgor loss point and greater dry weight fraction. Fall, compared to spring, tested seedlings had lower resistance to plant water movement and greater cuticular transpiration. In general, fall tested seedlings had more root growth than spring tested seedlings. Spring, compared to fall, tested seedlings generally had greater stress resistance.  相似文献   

13.
Abstract

When Scots pine (Pinus sylvestris L.) seedlings are short-day (SD) treated in May or early June, height growth ceases but seedlings reflush within a few weeks and grow secondary needles (later referred to as early SD treatment). These “2-year-old-like” seedlings have been thought to be more stress tolerant than traditional 1-year-old pine seedlings, and thus suitable for summer and autumn plantings. To test this, seedlings sown in April were early SD treated over a 3-week period from the beginning of June and the seedlings were planted at 10-day intervals from the beginning of July until the end of September, and also during the following spring. Neither survival nor height growth of early SD-treated seedlings differed from untreated (1-year-old) seedlings. Moreover, for both early SD-treated seedlings and 1-year-old seedlings, those planted in summer grew and survived better after planting but had more multiple leaders than seedlings planted in autumn or spring.  相似文献   

14.
In Mediterranean climates, seedlings are frequently shaded in the nursery to avoid heat damage and save water. However, the impact of this shading on the seedling quality and transplanting performance of Mediterranean species is not well known. We studied the effect of nursery shading on pre-planting features and post-planting performance of two Mediterranean tree species: the shade-intolerant pioneer Pinus halepensis and the shade-tolerant late-successional Quercus ilex. We grew one-year-old seedlings of both species under 100, 40 and 5% full sunlight. Shade had a low impact on the morphology and physiology of Q. ilex seedlings. In pines, only the deep shade treatment produced low quality seedlings with poor root development. In both species, transference to high light at planting in autumn did not impose any additional stress than that caused by frosts, but initial root growth was impaired in the two shaded treatments in pine. Post-planting growth and survival of oak seedlings showed no difference between treatments. Pine seedlings grown in deep shade showed higher mortality and lower growth after planting than those grown in full sun and intermediate light treatments, while intermediate light only reduced growth. For the nursery culture of Q. ilex seedlings, we advise using low light levels during summer to save water without impairing field performance. In P. halepensis, seedlings should be cultured under full sunlight conditions to maximize post-planting growth, but they can be cultured under intermediate light without impairing survival.  相似文献   

15.
Successful forest restoration requires planting quality seedlings with optimal growth potential. Thus, nurseries need to produce seedlings with plant attributes that favor the best chance of successful establishment once they are field planted. From the mid-twentieth century on, research foresters have critically examined plant attributes that confer improved seedling growth under various restoration site conditions. This review examines the value of commonly measured seedling quality attributes (i.e., height, diameter, root mass, shoot-to-root ratio, drought resistance, freezing tolerance, nutrient status, root growth potential, and root electrolyte leakage) that have been recognized as important in explaining why seedlings with improved attributes have better growth after planting. Seedlings with plant attributes that fall within the appropriate range of values can increase the speed with which they overcome planting stress, initiate growth, and become “coupled” to the forest restoration site, thereby ensuring successful seedling establishment. Although planting high quality seedlings does not guarantee successful seedling establishment, it increases chances for successful establishment and growth.  相似文献   

16.
Impacts of nursery short-day treatments on the survival, growth and needle damage of about 5,000 1 + 0 container white spruce (Picea glauca [Moench] Voss) seedlings from a single seedlot were studied for two growing seasons following planting on July 22, 1999 at four boreal reforestation sites in Northern Alberta, Canada of varying soil texture, drainage, aspect, slope, and slope position. Each site was separated into two areas that were site-prepared by either ripping or mounding. When seedlings reached a height of about 20 cm under normal greenhouse growth conditions, the seedlings from different germination dates over a 7-week period were exposed to one of five different conditioning treatments (T), mainly through varying the duration of 12-h short-day exposure to 0 (T0), 3 (T3), 7 (T7), 10 (T10), or 15 (T15) days followed by different periods of reduced N supply. N-reduction produced few differences in needle nutrient concentrations and so was not considered a likely cause of differences in field performance. The treatments progressively (from T0 to T15) increased tolerance to drought and frost, and resulted in a similar seedling size for T3, T7 and T10 (planting height of 21 cm and ground diameter of 2.9 mm) although T0 seedlings were smaller (20 cm) and T15 taller (24 cm). The weather in 1999 was dry, particularly in the weeks immediately before and after planting, but relatively moist and favorable in 2000 and 2001 apart from one major frost event (−7°C) in May 2000. Survival, growth and needle damage varied substantially among sites and short-day treatments, and the treatment differences were largely consistent across the four sites. In general the growth was better on the ripped than on the mounded areas. Seedlings in T7 (intermediate tolerance) survived and grew best in the first year but T0 (actively growing) did best during the second year. After 2 years, no differences were observed among T0, T3 and T7 in mortality (18%) and total height growth (15 cm). However, T10 and T15 had higher mortality (24 and 43%), and lower height growth (12 and 10 cm, respectively). The percentage of seedlings showing very severe needle damage after 2 years increased from T0 through T15 (14–33%). New root egress in the field also differed significantly among treatments and was positively and highly correlated with survival rate and growth. These results suggest that a longer short-day regime, as in T10 or T15, may be counterproductive and a shorter regime may be more effective in improving the performance of summer-planted white spruce seedlings.  相似文献   

17.
该文报道了薄壳山核桃大田播种育苗和火箭盆、无纺布、塑料钵容器等育苗方式对苗木生长及根系结构的影响.结果表明:不同育苗方式对薄壳山核桃苗木高度和地径生长影响显著,其中火箭盆容器培育的苗高、地径生长量最大,为39.14 cm和0.96 cm;无纺布容器苗和大田播种苗次之;塑料钵容器苗的苗高、地径生长量最小.多重比较分析表明,不同育苗方式对薄壳山核桃苗木的主根长度、主根直径、1级侧根数、1级侧根平均长度、根鲜质量、根干质量、茎鲜质量、茎干质量、根茎鲜质量比和根茎干质量比等指标影响显著,火箭盆容器和无纺布容器培育的苗木侧根系发达,根系质量好;而大田播种苗和普通塑料容器苗的主根发达,侧根少,根系质量较差.  相似文献   

18.
In order to re-inoculate soil with mycorrhizal fungi, small amounts (about 150 ml) of soil from an established Douglas-fir plantation were added to planting holes when Douglas-fir seedlings were planted on an old, unrevegetated clearcut in the Klamath Mountains of Oregon. Seedlings were lifted throughout the growing season to determine the influence of soil transfer on the rate of root tip initiation and mycorrhiza formation. Six weeks after planting, seedlings receiving plantation soil had formed 62% more root tips than controls; however, no statistically significant differences were apparent 15 weeks after planting. By that time, a small percentage of root tips were visibly mycorrhizal; seedlings receiving transferred soil had the most colonization (13.6 vs 3.5 per seedling, p 0.05). Of seedlings receiving transfer soil, 36.6% survived the first growing season, compared to 11.3% of control seedlings. At this high elevation, soils often remain frozen well into spring, leaving only a brief period betwen the time when soils become warm enough for root growth and the onset of summer drought. Under these conditions, the rapid root growth and mycorrhiza formation stimulated by plantation soil increases the ability of seedlings to survive the first growing season.This is Paper 2341 of the Forest Research Laboratory, Oregon State University.  相似文献   

19.
压苗栽植是花椒抗旱造林的一个新的栽植方法.用这种方法造林,幼树根系发达,成活率、保存率高,幼树结果早,产量高。以2a生的1级苗压苗造林效果最好。春、夏、秋三季造林均有较高的保存率,但从幼树生长情况来看,春季优于夏季,夏季优于秋季。  相似文献   

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