不同育苗方式对薄壳山核桃苗木生长及根系结构的影响

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。     

不同措施对皖南地区薄壳山核桃育苗的影响

为探索播种时间、裸根苗套袋及拉枝角度对皖南地区薄壳山核桃苗木生长的影响,以不同品种和树龄的薄壳山核桃为试验材料,对比不同播种时间、裸根苗整株套袋处理、拉枝角度等处理中薄壳山核桃的生长量、成活率、结果短枝数量。结果表明:(1)冬播覆膜对种子出苗率无显著影响,对幼苗生长量有显著影响,冬播覆膜措施下的1年生苗地径比春播粗2.18 mm,苗高比春播高38.5 cm;(2)薄壳山核桃裸根苗移栽整株套袋处理的成活率与对照组间存在显著差异,整株套袋提高了裸根苗移栽的成活率;(3)薄壳山核桃拉枝角度为45°时与拉枝角度65°、85°和105°处理的平均结果短枝数均存在显著差异,拉枝角度在85°时结果短枝数最多。即薄壳山核桃冬播生长量比春播生长量大,裸根苗移栽套袋处理的成活率增加,拉枝角度处于85°短枝数最多。     

不同立地条件下红豆树容器苗与裸根苗造林对比试验

对红豆树(Ormosia hosiei)容器苗与裸根苗在3种不同立地条件下进行成活率、树高和胸径生长量造林对比试验。结果表明:红豆树在不同处理间造林,成活率、6年生幼树高和胸径生长量差异极显著,立地条件与苗木类型间的互作效应在成活率和胸径上呈极显著差异,在树高上无显著性差异;采用容器苗造林成活率、6年生幼树高和胸径生长量极显著大于裸根苗造林;不同立地条件下造林成活率、6年生树高和胸径生长量呈极显著差异,随着立地条件变差,容器苗与裸根苗之间的造林成活率、树高和胸径生长量差距逐渐拉大,对造林成效的影响依次为:胸径成活率树高。     

森林彩化工程苗木成活率样本调查

在森林彩化工程区块内设置苗木栽植成活率调查样本,并进行了对照调查。结果显示:同类立地条件、相同树种和相同年龄的苗木在不同季节栽植其成活率不同,成活率从高到低排序为春季、冬季、秋季和夏季;同类立地条件、相同树种和相同年龄的营养杯苗、带土球苗、裸根苗3种不同类型的苗木,在相同季节栽植其成活率不同,营养杯苗成活率最高,带土球苗成活率次之,裸根苗成活率相对低。分析表明,提高苗木栽植成活率,应尽量考虑在春季和秋末初冬的适宜季节进行苗木栽植为宜,应根据不同类型苗木特点与栽植要求采取不同的技术操作措施。一般来讲,在同等条件下以选择营养杯苗栽植为宜,选择带土球苗栽植的成活率比选择裸根苗栽植的成活率相对要高。     

杉木不同育苗方式苗木生长差异分析

在提升杉木(Cunninghamia lanceolata)轻基质容器育苗方法的基础上,从生长量、生物量,生长量区间分布,苗木质量等级评价以及根系生长状况等方面,探究1年生杉木实生轻基质容器苗和裸根苗的生长差异。结果表明:轻基质容器苗的平均苗高、平均地径分别为40.87、0.50 cm,均达到Ⅰ级苗出圃标准;裸根苗平均苗高43.35 cm,达Ⅰ级苗出圃标准,平均地径0.54 cm,仅达到Ⅱ级苗出圃标准。轻基质容器苗和裸根苗苗高分别有73.3%、74.2%分布在30~50 cm范围,苗高分布差异较小;轻基质容器苗地径有78.0%分布在0.3~0.6 cm范围,裸根苗仅为62.4%,说明轻基质容器苗地径生长更加均匀。轻基质容器苗侧根数量以及根冠比显著高于裸根苗,有利于提高造林成活率。采用沙床培育,可获得高质量等级和高出圃率的杉木轻基质容器苗。     

容器育苗技术要点

容器苗的根系是在容器内形成的,在出圃、运输、造林的过程中,根系得到容器保护,栽植成活率高,栽植后根系恢复生长快,没有裸根苗的短期停滞生长现象,有利于苗木的初期生长。近年来,河北坝上地区采用容器苗造林取得了较好的经济效益和生态效益。现将其方法介绍如下。     

苗木不同繁育方式对文冠果苗木生长的影响

以同批文冠果种子6种不同育苗技术来研究其对1a生苗木造林后生长性状的影响。结果表明:不同育苗方式对1a生文冠果苗木造林后的成活率、苗高和地径影响均为极显著,且三者间均存在着极显著的正相关关系;RPM容器苗成活率(87.00%)显著高于裸根苗(30.00%),而苗高(50.73cm)、地径(7.96mm)显著高于无纺布容器苗和裸根苗;GGR处理裸根苗效果显著,成活率提高110.43%,苗高提高95.56%。     

渭南市渭北黄土高原沟壑区侧柏造林试验

在渭南市渭北黄土高原沟壑区进行了侧柏不同苗木类型、不同苗龄的造林效果对比试验研究,试验结果表明:在黄土高原干旱沟壑区造林宜选用定植培育1a、苗高0.8~1.0m的侧柏容器苗,较裸根苗可提高成活率37.3个百分点;选用定植培育2a、苗高1.8~2.0m的侧柏苗,要带直径和高度不小于20cm的土球,较不带土球苗提高成活率40个百分点;栽后截除苗木顶梢和茎干枝叶的一部分,较不截可提高栽植成活率26.8个百分点。     

不同苗木种类在煤矿废弃地植被恢复中的试验研究

采用单因素随机区组设计试验,研究了裸根苗、带土球苗和容器苗在煤矿废弃地植被恢复过程中的生长情况。试验结果表明:不同种类苗木生长情况不同,苗木成活率、地径生长量以容器苗最高,分别为91.58%、6.71,以裸根苗最低,分别比容器苗低31.5%、79%;株高生长量以容器苗最高,为10.08,以带土球苗最低;苗木整体生长状况级以容器苗最好,能够很好地适应煤矿地生长环境,生长旺盛;煤矿地土壤条件差,在植被恢复过程中植物易采用容器苗以提高植株成活率,从而也提高了生态恢复效率。     

龙泉市3种主要树种的容器苗与裸根苗造林对比试验

对杉木(Cunninghamia lanceolata)、马尾松(Pinus massoniana)、木荷(Schima superba)3树种进行树种与苗木类型双因素造林对比试验。结果表明,2.5年生时,树种间新梢高、地径和冠幅生长差异极显著,生长量大小为杉木>马尾松>木荷,树种与苗木类型间互作效应不显著,属树种的遗传效应;容器苗与裸根苗间新梢高差异极显著,地径和冠幅则差异不显著;经多重比较,容器苗平均新梢高生长比裸根苗增产30.3%,效益显著,其中杉木增产14.5%,马尾松增产34.9%,木荷增产51.9%。     

Effects of Seedbed Density on One-Year-Old <Emphasis Type="Italic">Fraxinus angustifolia</Emphasis> Seedling Characteristics and Outplanting Performance

To assess the effects of seedling spacing on one-year-old seedling morphology in the nursery, seeds of three provenances of Fraxinus angustifolia were sown at five different seedling spacings within rows of two different spacings in the seedbed. Subsequent growth performance of one-year-old seedlings was assessed by planting in the forest. Within row spacings were: 4.3, 5.0, 6.3, 8.3, and 12.5 cm, and there were five rows at 20 cm apart, or three rows at 33 cm apart across the 1.2 m wide seedbeds. Both spacings within and between rows significantly affected shoot height, root collar diameter, root dry weight and shoot dry weight, but not root/shoot ratio. Wider spacings produced larger seedlings, but only the wider spacing within rows significantly increased fine and coarse root mass. Provenances showed significant differences in diameter, root/shoot ratio, and fine and coarse roots, and they also showed interactions with row spacings in height and diameter measurements. One year after outplanting, diameter growth was significantly related to provenance, and diameter growth was 88% greater for trees from 33 cm nursery row spacing than those from 20 cm nursery row spacing.     

Root characteristics and growth potential of container and bare-root seedlings of red oak (<Emphasis Type="Italic">Quercus rubra</Emphasis> L.) in Ontario,Canada

Root characteristics and field performance of container and bare-root seedlings of red oak (Quercus rubra L.) were compared during the first growing season after planting. Sixty seedlings of each stock type were planted on a clearfell and weed-free site near Restoule, Ontario. Twenty-four additional seedlings from each stock type were compared at the start of the study in terms of shoot and root parameters. Measurement of root and shoot parameters were repeated at three dates during the first growing season in the field. The root systems of container stock had a larger number of first order lateral long roots and were significantly more fibrous than bare-root stock. These differences were sustained throughout the first growing season. In terms of field performance, container seedlings had 100% survival and achieved significant increases in both biomass and shoot extension. Bare-root seedlings suffered 25% mortality, significant shoot dieback and more variable growth. The mean relative growth rate (RGR) of container seedlings increased throughout the study period to a maximum of 30 mg/g/day, whereas the mean RGR of bare-root stock remained close to or below zero. Overall, the container seedlings proved less prone to transplanting shock than the bare-root seedlings, most likely due to favourable root architecture and the pattern of root development. Further work may be warranted in container design, growing regimes and root architecture to fully realise the potential of container systems for the production of high quality red oak seedlings across a range of site conditions.     

Biomass and nutrient allocation in Douglas-fir and amabilis fir seedlings: influence of growth rate and temperature

Allocation of biomass and nutrients to current-year and one-year-old shoots and roots of two-year-old conifer seedlings with differing rates of growth was studied. Differences in growth rate were achieved by selecting fast- and slow-growing populations of the relatively fast- and slow-growing conifer species, Pseudotsuga menziesii (Mirb.) Franco and Abies amabilis Dougl. ex Loud, respectively. Environmentally controlled differences in growth rate were induced by placing half of the seedlings in a 10 degrees C growth chamber and half in a 20 degrees C growth chamber in their second growing season. Seedling samples were harvested in May, before the temperature treatment, and in July and November of the second growing season, and biomass and nutrient concentrations of current-year and one-year-old shoots and roots were determined. Seedling biomass and nutrient allocation differed among the high-growth treatments. Seedlings exhibiting high growth in response to the 20 degrees C treatment and faster growing populations within species both showed increased allocation to new shoots, whereas seedlings of the fast-growing species showed greater allocation to old shoots than to new shoots. Increased growth increased nutrient uptake, but nutrient concentration decreased with growth rate as a result of dilution, so that faster-growing seedlings had greater nutrient-use efficiency than slower-growing seedlings. Retranslocation of P and K was seen in the second year only in slow-growing populations at 10 degrees C. Nutrient concentrations of one-year-old plant parts decreased in the second year, indicating new growth was a stronger sink for nutrients than second-year growth.     

不同容器规格对樟子松育苗质量的影响

为探索樟子松(Pinus sylvestris var.mongolica)容器育苗的合理容器规格,以白色无纺布袋作为育苗容器,按照育苗容器口径和高度不同,设置6 cm×10 cm、10 cm×10 cm、12 cm×15 cm、15 cm×18 cm 4种容器规格,研究了不同容器规格对樟子松幼苗质量的影响。结果表明:随着容器规格的增大,樟子松幼苗的株高、地径、主根长、植株干鲜质量、根冠比和壮苗指数均呈增加趋势,但12 cm×15 cm和15 cm×18 cm两个规格容器对樟子松幼苗各项指标的影响差异不显著,而樟子松幼苗根系活力、可溶性蛋白和丙二醛均随着容器规格的增大呈先增加后降低趋势,并以12 cm×15 cm效果最佳。研究认为12 cm×15 cm规格的容器更适宜培育樟子松容器苗。     

Root growth potential, seedling morphology and bud dormancy correlate with survival of loblolly pine seedlings planted in December in Alabama

First-year survival of December-planted loblolly pine seedlings sampled from 20 nurseries ranged from 36 to 86%. Various characteristics of the seedlings including root growth potential (RGP), shoot/root ratio, root weight and stem length were correlated with survival. A regression model using the number of new roots >/= 0.5 cm and the shoot/root ratio accounted for 80% of the variation in first-year survival. Alone, the number of new roots >/= 0.5 cm accounted for 76% of the variation in survival. Foliar nutrients were not correlated with survival. Seedlings with a high proportion of quiescent buds at planting had a higher RGP and better survival than seedlings with dormant (endodormant) buds. The data suggest that seedlings with dormant buds should not be planted on sites where rapid new root growth is needed for survival.     

不同育苗基质对油茶芽砧嫁接苗生长的影响

通过对几种育苗基质对油茶芽砧苗成活率、苗高、地径以及根系等生长指标对比分析的结果表明,在4个基质配比中,1 a生芽砧嫁接苗以油茶轻基质容器苗保存率、树高和地径表现为最大,分别为82.2%,32.1 cm和0.31cm;苗木根系以2 a生大田裸根苗主根为最长,为13.3 cm,根茎比最大,为0.50,适宜油茶造林后后期生长。因此培育1 a生油茶苗以油茶轻基质为最佳选择,培育2 a生苗应该选择大田育苗。     

沙床育苗技术对杉木苗木生长影响的研究

对采用沙床育苗法培育的杉木轻基质容器苗的生长量、生物量、根系形态和出圃率等进行对比研究的结果表明:轻基质容器苗地径、侧根数、高径比在贝江河林场、西山林场和咸水林场等3个种子园的良种苗间均存在极显著差异。轻基质容器苗的苗高、地径、侧根数、地下鲜重、根冠比和出圃率分别为37.3 cm、5.5 mm、13.5条、5.1 g、0.29和94.5%,表明轻基质容器苗根系发达,出圃率高,对提高造林成活率和良种利用率具有重要意义。沙床培育轻基质容器苗技术利于培育出高质量和高出圃率的良种壮苗,宜在苗木培育与生产中大力推广。     

木荷轻基质网袋容器育苗技术

通过基质配比、容器规格、缓释肥用量及容器空气切根与否4个处理对1年生木荷容器苗生长性状差异进行研究,以选择出最佳的木荷容器育苗方案。结果表明:1年生木荷容器苗受基质和空气切根的影响不显著,其基质配比中泥炭比例达到50%即可。而缓释肥用量、容器规格对木荷1年生容器苗的苗高和地径生长影响显著,木荷1年生容器苗的苗高和地径生长量随缓释肥用量的增加而增大,缓释肥量2.5 kg/m3时其苗高和地径生长量最大,容器规格为4.5 cm×12 cm时生长表现最好。综合考虑容器苗生产成本,1年生木荷容器苗最佳育苗方案为:基质中泥炭-谷壳配比为5∶5,无纺布容器规格为4.5 cm×8 cm,基质中缓释肥量为2.5 kg/m3。     

木荷裸根苗和容器苗造林效果对比分析

采用一年生木荷容器苗和裸根苗在不同造林地类型上造林,比较造林效果。结果表明:木荷容器苗造林成活率和保存率在不同的造林地类型中均明显优于裸根苗。木荷容器苗造林树高生长和地径在不同的造林地类型中均明显优于裸根苗,并且差异显著。不同的造林地类型中,采伐迹地的成活率、保存率、树高生长量和地径生长量最好,其次为林冠下,再次为生物防火带。