黑松当年生苗切根培育试验

2001年冬季大田播种黑松，2002年出苗后，6月底每公顷定苗90万株左右。2002年7～9月，每月10日进行切根培苗试验，结果表明：1．5年生的黑松切根苗与未切根苗相比，切根能有效促进苗木生长和根系发育，提高Ⅰ级苗比率。7，月10日切根效果最好，Ⅰ级苗达到91．2％，8月10日和9月10日切根苗Ⅰ级苗比率分别为85．1％，78．2％，未切根对照苗Ⅰ级苗比率仅为63．5％。     

松类育苗苗期二次切根试验初报

通过应用自行研制的人工简易切根器对火炬松芽苗切根移栽苗木苗期二次切根试验表明，切根时间以８月份为宜，切根深度以８ｃｍ为宜。二次切根苗比芽移切根苗苗高下降１７．３％，地径增加４．３％，侧、须根数增加１４３．３％，侧须根长增加８６．４％，根重增加２６．７％。应用二次切根苗木造林比对照苗成活率提高１６．２％，１年生林不当年抽高生长提高１６．２％。应用该种切根器每天可切根０．０６７～０．０８ｈｍ２。     

松类育苗苗期二次切根试验初报

通过应用自行研制的人工简易切根器对火炬松芽苗切根移栽苗木苗期二次切根试验表明，切根时间以８月份为宜，切根深度以８ｃｍ为宜。二次切根苗比芽移切根苗苗高下降１７．３％，地径增加４．３％，侧、须根数增加１４３．３％，侧须根长增加８６．４％，根重增加２６．７％。应用二次切根苗木造林比对照苗成活率提高１６．２％，１年生林木当年抽高生长提高１６．２％。应用该种切根器每天可切根０．０６７￣０．８ｈｍ＾２。     

沙区樟子松苗期干物质的研究

通过对樟子松 1年生留床苗、2年生留床切根苗、2年生移植 (未切根 )苗的干物质比较 ,结果表明 :含水量 ,2年生切根苗 <未切根 2年生苗 <1年生苗 ;生物量 ,2年生切根苗各部位干物质量 >2年生未切根苗各部位干物质量 >1年生苗各部位干物质量 ,1、2年生苗干物质主要由地上部分组成。研究结果为 :切根苗质量超过未切根苗 ,一级苗数量多于未切根苗 ;苗木在苗期积累了大量干物质 ,根系及径生长旺盛 ,樟子松在苗期非常适合沙区     

切根和施肥对银杏大苗生长的影响

为探讨切根和施肥对银杏Ginkgobiloba裸根大苗生长的影响,同时为了缩短移栽后的缓苗期,2013-2014年在浙江省长兴县选取了15年生实生银杏裸根苗24株,2015-2017年选取了5~10年生实生银杏裸根苗72株,分别进行了两次切根和施肥试验,第一次的试验结果表明:一次切掉1/2的侧根,对苗木胸径、树高生长无明显影响,切根一年后侧根上细根数量大幅增加。第二次的试验结果表明:切根处理的苗木胸径、树高增长量均低于对照CK的增长量,但差异不显著,说明切根对银杏裸根苗的生长有所抑制,但影响不大;在不切根时,施肥对苗木树高的促进作用较为显著,同时切根与开沟施肥时,对银杏树高和胸径生长均有一定的抑制作用。两因素(切根与施肥)的主效应和交互效应分析显示,对于树高生长,切根与否不是影响树高生长的主要因素,施肥才是;对于胸径生长,则恰好相反;不管是对树高生长还是胸径生长,两因素间均存在交互作用,同时也表明分期切根和开沟施肥可作为实用技术推广到生产实践中。     

马尾松不同苗木造林初期效果分析

从马尾松不同处理苗木造林3年生调查分析表明,马尾松截根移栽或切根裸根苗造林效果最好,根系发达,可提高造林成活率和幼林生长,且造林成本适中,而常规裸根苗造林效果差。在林业生产中应大力推广马尾松切根苗造林。     

切根对马尾松苗木及造林初期生长的影响

为提高马尾松苗木质量和造林质量,本文分析了切根对马尾松苗木及造林初期的生长特征。结果表明:切根对马尾松苗木及造林初期生长具有显著的影响。马尾松切根苗苗高、主根长不如对照组,但地径、侧根数、侧根长显著优于未切根苗,径高比的改善提高了苗木质量,有利于提高马尾松造林保存率。造林3年后,切根苗木高生长与未切根苗木相当。     

松类育苗二次切根

松类育苗二次切根江西省宜黄县造林项目办刘克潮等１９９３年用人工简易切根器在苗期对芽苗切根移栽培育的火炬松苗木进行了第二次切根试验。和芽苗切根苗比较，苗高下降１７．３％，地径增加４．３％，侧、须根数增加１４３．３％，侧须根长增加８６．４％，根重增加２６...     

马尾松苗切根技术研究

通过马尾松苗切根试验，明显提高了苗木质量，切根的最佳时间为８月分，深度８ｃｍ左右，切根苗宜在砂质土壤上进行条播为好。     

三尖杉切根育苗及造林成效的研究

对比试验表明,三尖杉小苗定距移栽切主根1/2～1/3,苗木质量优于无切根,切根是培育三尖杉壮苗的主要技术措施。应用切根苗造林,造林成活率较无切根苗高,幼林生长也更快。     

苗木切根技术研究进展

精准培育的理念已经渗入到森林培育的各个环节。切根作为干扰根系最为重要的技术,也受到越来越多地重视。切根可以划分为芽苗切根、苗期切根和起苗后切根等3种类型,把平截、扭根、侧方修根、盒式修根等称为苗期切根,是狭义切根范畴。结合苗木形态指标、生理指标和造林效果,综述每一类型的切根对苗木质量和造林效果的影响。以辐射松为代表的主根发达树种,通过芽苗切根、苗期的平截和扭根,抑制根系顶端优势,从而降低苗木高生长,促进侧根发育,形成发达、紧凑的根系,调整苗木地上和地下比例,最终提高苗木造林效果。以花旗松为代表的慢生常绿树种,侧根较为发达,切根效果不一。苗木平截和扭根后,内源激素、矿质营养、碳水化合物、水分等均会发生变化,这种变化如何影响苗木质量的机制尚不明确。     

Growth of graded sweetgum 3 years after root and shoot pruning

Nursery grown 1–0 bareroot sweetgum seedlings were lifted and graded into two diameter classes (12–16 and 4–8 mm) during the dormant season. Large and small grades were top and/or root pruned and then outplanted on two sites in the lower Coastal Plain of the southeastern United States. Seedling shoots were pruned to 50% of tree height, a 5 cm stump, or no pruning. Seedling roots were pruned to a 15 cm length or left unpruned. Site affected survival but not growth. Smaller, top pruned seedlings performed worse on one site, probably due to greater weed competition. Large seedlings increased survival and growth which increased 3 year average plot volumes by 89%. Top pruning stimulated height growth, but reduced diameter growth and decreased third year seedling volumes. Root pruning did not affect seedling growth. Diameter growth may better indicate treatment impact that height, which has been most commonly used in previous studies.     

Effect of density control and undercutting on root morphology of 1+0 bareroot hardwood seedlings: five-year field performance of root-graded stock in the central USA

The Hardwood Quality Nursery Cooperative (bareroot forest nurseries in 5 midwestern states) initiated a series of studies in 1987 to evaluate red oak (Quercus rubra L.), and black walnut (Juglans nigra L.) seedling performance as a function of cultural treatments and seedling root system morphology.Seedlings were grown at three densities (32, 64, and 128 stems m^-2for red oak; 32, 64, and 96 stems m^-2for black walnut), and half of the density plots were undercut. Seedlings received fertilizer, weeding, and irrigation treatments customary to their respective nurseries. Seedlings were lifted, measured, and outplanted in their respective states as completely random individual tree plots during spring 1988. Survival, height, and diameter were evaluated annually through 1992.Seedling height, diameter, and number of permanent first-order lateral roots (FOLR) decreased with increasing bed density. At a given density, undercutting produced smaller seedlings (for both height and diameter) that had greater numbers of FOLR. Numbers of FOLR influenced seedling performance after outplanting. Red oak seedlings with at least 5 FOLR and black walnut with at least 7 FOLR had better survival and growth than seedlings with fewer roots.     

修剪和生长调节剂对青海云杉苗芽生长发育的影响

对5年生和7年生青海云杉苗进行了不同方式的修剪,同时用不同的生长调节剂对其主干和侧枝上的芽进行了处理,发现除去青海云杉顶芽,能够促进苗木侧芽和隐芽的生长发育,提高侧芽的抽枝率,增加新枝的生长量.不同种类的生长调节剂和修剪方式对青海云杉芽的生长发育影响效果显著不同,去顶芽修剪的效果优于纺锤形修剪和篱式修剪,对于7年生苗,主干上仅留3个饱满芽的强度修剪能明显地减少主干上的芽数,使抽枝数也随之减少,处理效果最差.去顶芽能够明显的增加当年新梢数量和长于6 cm的新梢总长度,同时还能增加当年新梢上冬芽数.6BA对青海云杉芽和枝条的生长发育有较好的促进作用,抽枝宝在各个修剪处理中表现均最差,甚至在一定程度上抑制了青海云杉芽的萌发和延长生长.修剪和生长调节剂处理对5年生苗侧枝芽抽枝数影响均极显著,而对7年生苗的影响却不显著;修剪和生长调节剂的交互作用明显地影响了对7年生苗的处理效果,而对5年生苗的影响不显著.去顶芽后再用6BA涂抹青海云杉苗上的保留芽,能有效地促进青海云杉保留芽的生长发育,有利于形成更多枝条,对青海云杉采穗圃苗的处理效果最佳,强度修剪和用抽枝宝抹芽不适于青海云杉采穗圃苗的培育.     

遮阳网遮光度对红椎大田播种育苗效果的影响

设置了4种不同的遮光处理:全光照、遮光度40%、遮光度60%、遮光度70%,探讨不同遮光度对红椎大田播种育苗苗木保存率和苗木生长的影响。结果表明:遮光度对红椎大田播种育苗苗木保存率和苗木生长有显著影响。遮光度达70%时,其苗木保存率、苗木高生长与地径生长均表现最佳。     

Field performance of Quercus petraea seedlings grown under competitive conditions: influence of prior undercutting in the seedbed

Quercus petraea was undercut according to the following procedure: undercutting first year once (July, September, November), twice (July and November), or undercutting in two consecutive years (September of year 1 and either July, September or November of year 2). Undercutting decreased height and dry weight of the seedlings compared to uncut control seedlings. Undercutting in September and July in two consecutive years increased the number of first-order lateral roots. Field performance was evaluated by transplanting under two conditions, (a) competition with a mixture of grasses with no irrigation or fertilisation and (b) standard conditions with fertilisation and irrigation first year and no competition with grass. After two growing seasons under competitive conditions, seedlings undercut in September of year 1 had a significantly higher dry weight compared with that of uncut control seedlings. Numbers of lateral roots and field performance under competitive conditions was related when numbers of lateral roots were small, but not when high. Competitive conditions had limited effect on root growth after one growing season, whereas shoot growth was reduced. After two growing seasons both shoot and root growth were reduced in all treatments compared with standard conditions.     

Stock quality assessment through an integrated approach

Forest regeneration can be improved by matching seedling stock with reforestation site environmental conditions. To achieve this improvement, one must characterize seedling performance potential with anticipated field site conditions. A theoretical performance potential index (PPI) has been developed to forecast seedling field performance during the first growing season on a reforestation site. PPI includes material and performance attribute tests that characterize seedling performance potential under optimum and limiting environmental conditions. Test results are standardized and then integrated resulting in a comprehensive assessment procedure. The PPI concept is demonstrated using containerized western hemlock (Tsuga heterophylla (Raf.) Sarg.) seedlings subjected to a series of dormancy induction treatments and the results are compared with actual seedling performance during the first growing season on a reforestation site. Results indicated that PPI values for western hemlock seedlings treated with various dormancy induction treatments corresponded to field performance. Possible use of PPI in stock selection is discussed.     

三尖杉育苗技术研究

通过三尖杉播种、扦插育苗试验,研究不同种源种子、不同穗条及不同生根剂处理对三尖杉苗木繁殖的影响,结果表明:福建柘荣和安徽黄山种源的种子相似,与云南易门种源的种子相比,种子外形较大,发芽率高,实生苗生长较快。穗条采用ABT1250 mg.L-1+双吉尔250 mg.L-1浸泡10 h,扦插生根率最高;幼龄母树比老龄母树、顶梢比不带顶梢、萌条比树冠上的穂条的扦插成活率高;三尖杉扦插苗木偏冠现象明显,偏冠现象同穗条采条的位置、穗条年龄有关,幼龄母树萌条带顶梢穗条的扦插苗偏冠率最低,老龄母树不带顶梢穗条的扦插苗偏冠率最高。     

Physiological and phenological responses of oak seedlings to oak forest soil in the absence of trees

Established trees influence the growth and physiology of seedlings by altering above- and belowground conditions; however, tree influences on seedling physiology via belowground interactions are not well understood. We used soil transfers to an open field to examine the belowground influences of a Quercus ellipsoidalis E.J.Hill dominated forest on Q. ellipsoidalis seedling mycorrhizal infection, nutrient uptake, growth and photosynthesis over three years. After two years, seedlings planted with large quantities of forest soil (HF treatment) had greater leaf mass and foliar N concentrations than seedlings receiving smaller quantities of forest soil (LF) and control treatments. Mycorrhizal infection was greater in the HF treatment after one year compared with the LF and control treatments, with a positive correlation of foliar N and mycorrhizal infection in Year 2. There were marked effects of treatments on seedling spring phenology with HF seedlings breaking bud up to 17 days earlier than seedlings in the other treatments. The HF seedlings also had more rapid leaf expansion and larger leaves, and an increase in net photosynthetic rates. These results highlight complex linkages between above- and belowground physiology: forest soil had substantial effects on seedling physiology, including traits such as phenology that have previously been considered to be under aboveground control. Belowground influences of trees on conspecific seedlings may play a critical role in early seedling establishment.     

国外容器苗质量调控技术研究进展

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.