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为研究不同育苗容器对'吉美'海棠(Malus'Jimei')生理特性的影响,以'吉美'海棠为对象,选择3种类型容器(控根容器、无纺布袋和营养钵)栽植'吉美'海棠苗木,测定其相关生理指标,以期找到最佳育苗容器类型.试验结果表明,无纺布袋30cm×30cm(直径×高)可作为'吉美'海棠苗木的最佳育苗容器类型. 相似文献
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采用ECH2O含水量监测系统,对侧柏容器苗留袋、脱袋造林后容器水分动态及苗木生长及生物量进行监测。林地土壤平均含水量>脱袋造林>留袋造林。根系数量、根系分布、苗木生长状况、标准株生物量脱袋造林均优于留袋造林。大规格移植容器苗造林时,在确保苗木根团完整的情况下,以采用脱袋造林栽植方式为好。 相似文献
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比较了在美植袋物理控根容器中以及大田条件下生长的3年生玉兰苗的生长量、根系构型和透根情况,结果表明:美植袋培育的玉兰苗的生长量与大田培育的玉兰苗无显著差异,但在根系构型上有显著不同,美植袋中生长的玉兰苗在距离主干20 cm范围内的吸收根(根系直径在0 2 mm的根系)的根尖数、根表面积和根体积分别为12 996.66个·株-1,1 674.4 cm2·株-1,40.82 cm3·株-1,疏导根(根系直径在2 5 mm的根系)的根尖数、根体积和根表面积分别为195.09个·株-1,969.09 cm2·株-1,67.73 cm3·株-1,明显大于大田培育的玉兰苗,具有更高的吸收和疏导能力。垂直方向上,美植袋中生长的玉兰苗在距离容器顶端21 33 cm具有较多的疏导根和吸收根,水平方向上,在距离容器侧壁0 14 cm处具有较多的吸收根和疏导根。在这区域内吸收根和疏导根的体积和面积均占根系总体积和表面积的71.5%,根系构型发生了明显改变。美植袋容器使用3年后,已经老化,出现了透根现象,透出的根系主要是直径在0 1 mm的细根和直径大于10 mm的粗根。 相似文献
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控根容器对苗木根系构型和造林成活率的影响 总被引：1，自引：0，他引：1
为了提高苗木质量和移栽成活率,比较了控根容器和普通容器对舟山新木姜子和红楠苗木根系构型和移栽成活率的影响。结果表明:控根容器培育比普通容器的苗木根系长度增长率分别高13.3%和10%,0.5mm以下细根数量分别多8.4%和7.5%,根系表面积增长率分别多19.8%和16.8%,根系生物量垂直分布上移,整体比重更加均匀,移栽后成活率分别提高15.8%和10.5%,而且可以实现全年造林。试验证明,控根容器可以显著改善苗木根系构型,提高造林成活率,值得推广。 相似文献
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容器规格、基质配比对菩提树容器苗生长及生理的影响 总被引：1，自引：0，他引：1
《经济林研究》2021,39(3)
【目的】筛选适合菩提树容器苗生长的最佳容器规格及基质配比,为完善我国北方地区菩提树容器育苗技术提供参考。【方法】采用双因素随机区组试验设计,按照直径和高度设置3种容器规格,以园土、育苗土、珍珠岩、蛭石为基质材料,设置5个水平的基质配比,共15种组合,测定不同处理组合下菩提树容器苗的株高、地径和生物量等生长指标以及叶绿素含量、可溶性糖含量、可溶性蛋白含量等生理指标,并进行主成分分析及综合评价。【结果】容器规格和基质配比对菩提树容器苗生长规律的影响显著。6—8月为菩提树容器苗株高的速生期,株高以A1B5处理组合(A1:15 cm×20 cm美植袋;B5:20%园土+30%育苗土+10%珍珠岩+40%蛭石)较优;9月为地径增长的速生期,地径生长以A1B4处理组合(B4:40%园土+30%育苗土+10%珍珠岩+20%蛭石)较优。不同容器规格处理中,A1处理下菩提树容器苗的生物量、苗木质量指数极显著高于A2(18 cm×23 cm)、A3(20 cm×30 cm)处理,A2处理下叶绿素含量、可溶性糖含量、可溶性蛋白含量等生理指标显著高于A1和A3处理,小规格的容器明显有利于菩提树容器苗株高、地径的生长及生物量的累积。不同基质配比处理中,B5处理下生物量、苗木质量指数、高径比等生长形态指标以及叶绿素含量、可溶性糖含量、可溶性蛋白含量等生理指标均显著高于其他基质配比处理。综合评价结果表明,15个容器规格和基质配比的组合中,A2B5、A1B5组合较优。【结论】随着容器规格的增大,菩提树容器苗的苗木质量指数降低,15 cm×20 cm美植袋最适宜菩提树容器苗生物量的累积,为最佳容器规格。20%园土+30%育苗土+10%珍珠岩+40%蛭石为其最佳基质配比,可以更好地促进菩提树容器苗的生长。 相似文献
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《Scandinavian Journal of Forest Research》2012,27(1-4):547-556
Fungi were isolated from the roots and growth substrate of bare‐rooted and containerized Pinus sylvestris and Picea abies nursery seedlings displaying a root dieback. Isolations were also made from visually healthy seedlings. The potential pathogenicity of all isolated species was determined in laboratory trials. Cylindrocarpon spp., Fusarium spp. and Trichoderma viride were frequently isolated. The isolation frequency of a uninucleate Rhizoctonia‐like fungus, Pythium spp. and Phytophthora imdulatum from diseased containerized seedlings and their pathogenicity in tests suggest that these fungi are likely involved in the root dieback disease in containers. The pathogenic Rhizoctonia‐like fungus in addition to Pythium spp. was also isolated from bare‐rooted seedlings. In greenhouse tests Pythium spp. were more pathogenic to 4‐week‐old Scots pine seedlings grown before transplantation in unsterile substrate than to those seedlings grown axenically in agar. External factors are considered to have some role in the expression of disease. 相似文献
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Plant roots play important roles in acquisition of water and nutrients, storage, anchoring, transport, and symbiosis with soil microorganisms, thus quantitative researches on root developmental processes are essential to understand root functions and root turnover in ecosystems,and at the same time such researches are the most difficult because roots are hidden underground. Therefore, how to investigate efficiently root functions and root dynamics is the core aspect in underground ecology. In this article, we reviewed some experimental methods used in root researches on root development and root system architecture, and summarized the advantages and shortages of these methods. Based on the analyses, we proposed three new ways to more understand root processes:(1) new experimental materials for root development;(2) a new observatory system comprised of multiple components, including many observatory windows installed in field, analysis software,and automatic data transport devices;(3) new techniques used to analyze quantitatively functional roots. 相似文献
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B. J. Wang W. Zhang P. Ahanbieke Y. W. Gan W. L. Xu L. H. Li P. Christie L. Li 《Agroforestry Systems》2014,88(5):835-850
A field study was conducted at Hetian, southern Xinjiang, northwest China, to investigate root morphology as affected by interspecific interactions between jujube (Ziziphus jujuba Mill.) and wheat (Triticum aestivum L.). The treatments comprised (1) sole wheat, (2) 3-, 5- and 7-year-old sole jujube trees, and (3) intercropping of wheat/3-, 5- and 7-year-old jujube trees. Roots were sampled by auger in each plot down to 100 cm depth at 20 cm intervals in the soil profile and horizontally up to 150 cm away from the base of the trees at 30 cm intervals. All jujube/wheat intercropping systems had advantages of intercropping with a land equivalent ratio (LER) >1. There were significant differences in the contours of both root length density (RLD) and root diameter (RD) in intercropped wheat and jujube in the vertical and horizontal direction at corresponding soil depths but the RLD and RD of the 7-year-old jujube/wheat intercropping system were less influenced by intercropping in this respect than 3- and 5-year-old jujube intercropped with wheat. The roots of both intercropped wheat and jujube had smaller RLD, RD and larger specific root lengths (SRLs) at corresponding soil depths than did sole wheat and jujube. The older the jujube the larger were the SRL values of intercropped wheat and the smaller the RLD and RD of intercropped wheat. The greater the distance from the jujube the less influence there was on the RLD, SRL and RD of intercropped wheat and jujube and the greater the distance from the jujube the smaller was the SRL of intercropped wheat and the greater the RLD and RD of intercropped wheat (but still less than the monoculture wheat). The older the jujube the more developed were the jujube roots so that the smaller the SRL of jujube the bigger the RLD and RD of jujube. Jujube tree roots showed a mainly downward trend and extended laterally 150 cm from the trees resulting in the roots of the jujube trees and the wheat having niche overlap at a soil depth of 20–40 cm. The mechanisms underlying the thinner roots of wheat and jujube require further investigation. 相似文献
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Root respiration may account for as much as 60% of total soil respiration. Therefore, factors that regulate the metabolic activity of roots and associated microbes are an important component of terrestrial carbon budgets. Root systems are often sampled by diameter and depth classes to enable researchers to process samples in a systematic and timely fashion. We recently discovered that small, lateral roots at the distal end of the root system have much greater tissue N concentrations than larger roots, and this led to the hypothesis that the smallest roots have significantly higher rates of respiration than larger roots. This study was designed to determine if root respiration is related to root diameter or the location of roots in the soil profile. We examined relationships among root respiration rates and N concentration in four diameter classes from three soil depths in two sugar maple (Acer saccharum Marsh.) forests in Michigan. Root respiration declined as root diameter increased and was lower at deeper soil depths than at the soil surface. Surface roots (0-10 cm depth) respired at rates up to 40% greater than deeper roots, and respiration rates for roots < 0.5 mm in diameter were 2.4 to 3.4 times higher than those for roots in larger diameter classes. Root N concentration explained 70% of the observed variation in respiration across sites and size and depth classes. Differences in respiration among root diameter classes and soil depths appeared to be consistent with hypothesized effects of variation in root function on metabolic activity. Among roots, very fine roots in zones of high nutrient availability had the highest respiration rates. Large roots and roots from depths of low nutrient availability had low respiration rates consistent with structural and transport functions rather than with active nutrient uptake and assimilation. These results suggest that broadly defined root classes, e.g., fine roots are equivalent to all roots < 2.0 mm in diameter, do not accurately reflect the functional categories typically associated with fine roots. Tissue N concentration or N content (mass x concentration N) may be a better indicator of root function than root diameter. 相似文献
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Variations of fine root diameter with root order in Manchurian ash and Dahurian larch plantations 总被引：1，自引：0，他引：1
Xiangrong Wang Zhengquan Wang Youzhi Han Jiacun Gu Dali Guo Li Mei 《Frontiers of Forestry in China》2007,2(1):34-39
Fine root lifespan and turnover play an important role in carbon allocation and nutrient cycling in forest ecosystems. Fine
roots are typically defined as less than 1 or 2 mm in diameter. However, when categorizing roots by this diameter size, the
position of an individual root on the complex lateral branching pattern has often been ignored, and our knowledge about relationships
between branching order and root function thus remains limited. More recently, studies on root survivals found that longevity
was remarkably different in the same branching level due to diameter variations. The objectives of this study were: (1) To
examine variations of fine root diameter from the first-to fifth-orders in Fraxinus mandshurica Rupr and Larix gmelinii Rupr roots; and (2) To reveal how the season, soil nutrient, and water availability affect root diameter in different branch
order in two species. This study was conducted at Maoershan Forest Research Station (45°21′–45°25′N, 127°30′–127°34′E) owned
by Northeast Forestry University in Harbin, northeast China. Both F. mandshurica and L. gmelinii were planted in 1986. In each plantation, fine roots of two species by sampling up to five fine root branch orders three
times during the 2003 growing season from two soil depths (i.e., 0–10 and 10–20 cm) were obtained. The results showed that
average diameters of fine roots were significantly different among the five branch orders. The first-order had the thinner
roots and the fifth order had the thickest roots, the diameter increasing regularly with the ascending branch orders in both
species. If the diameter of fine roots was defined as being smaller than 0.5 mm, the first three orders of F. mandshurica roots and the first two orders of L. gmelinii roots would be included in the fine root population. The diameter ranges of the fine roots from first-order to fifth-order
were 0.15–0.58, 0.18–0.70, 0.26–1.05, 0.36–1.43, and 0.71–2.96 mm for F. mandshurica, and 0.17–0.76, 0.23–1.02, 0.26–1.10, 0.38–1.77, and 0.84–2.80 mm for L. gmelinii. The average coefficient of variation in first-order roots was less than 10%, second-and third-order was 10–20%, and fourth-and
fifth-order was 20–30%. Thus, variation in root diameter also increased with the ascending root order. These results suggest
that “fine roots”, which are traditionally defined as an arbitrary diameter class (i.e., <2 mm in diameter) may be too large
a size class when compared with the finest roots. The finest roots have much shorter lifespan than larger diameter roots;
however, the larger roots are still considered a component of the fine root system. Differences in the lifespan between root
diameter and root order affect estimates of root turnover. Therefore, based on this study, it has been concluded that both
diameter and branch order should be considered in the estimation of root lifespan and turnover.
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Translated from Acta Phytoecologica Sinica, 2005, 29(6): 871–877 [译自: 植物生态学报] 相似文献
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《Scandinavian Journal of Forest Research》2012,27(1-4):233-242
Scots pine and different provenances of lodgepole pine were compared in regard to root characteristics and the distribution of biomass within individual trees. Tap root formation was more frequent and the root/shoot ratio was higher on Scots pine than on lodgepole pine but significant variation of these traits was found between provenances of planted lodgepole pine. A non‐destructive method for estimation of root biomass was developed. 相似文献
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Fine root distribution and structural root characteristics of four-years-old multipurpose woody species with potential for
use in agroforestry systems were investigated on an Alfisol in the forest savanna transition zone of south-western Nigeria.
Rooting patterns of woody species studied differed considerably. Lonchocarpus sericeus had the lowest percentage (21%) of
total fine roots confined to the upper (0 to 30 cm) soil layer, compared to 84% with Tetrapleura tetraptera. Despite the superior
tap root system of Enterolobium cyclocarpum and the fine root form of Nauchlea latifolia however, their extensive distribution
and very large lateral woody root volume density may pose a major problem for seedbed preparation and tillage operations in
simultaneous agroforestry systems. Lonchocarpus sericeus appears to have the most desirable structural and fine root architecture
among the species studied for simultaneous agroforestry systems. The total root density below the underlying distal soil layers
was linearly related to the sum of square of tap root diameter and the corresponding soil depths.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
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对刺槐根瘤形成过程中传递细胞的功能作了初步探讨。研究发现，接种根瘤菌的刺槐幼苗其鲜重、干重均高于同期培养的未接菌的刺槐苗。接菌刺槐幼苗的含水率也略高于同期未接菌的刺槐幼苗，但差异不显著。作元素分析，同一时期接种根瘤菌的刺槐幼苗根段磷、钾、镁、铁、锰、锌各元素含量均高于未接菌的对照刺槐苗。 相似文献
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By influencing belowground processes, streamside vegetation affects soil processes important to surface water quality. We
conducted this study to compare root distributions and dynamics, and total soil respiration among six sites comprising an
agricultural buffer system: poplar (Populus × euroamericana‘ Eugenei), switchgrass, cool-season pasture grasses, corn (Zea
mays L.), and soybean (Glycine max (L.) Merr.). The dynamics of fine (0--2 mm) and small roots (2--5 mm) were assessed by
sequentially collecting 35 cm deep, 5.4 cm diameter cores from April through November. Coarse roots were described by excavating
1 × 1 × 2 m pits and collecting all roots in 20 cm depth increments. Root distributions within the soil profile were determined
by counting roots that intersected the walls of the excavated pits. Soil respiration was measured monthly from July to October
using the soda-lime technique. Over the sampling period, live fine-root biomass in the top 35 cm of soil averaged over 6 Mg
ha-1 for the cool-season grass, poplar, and switchgrass sites while root biomass in the crop fields was < 2.3 Mg ha-1 at its maximum. Roots of trees, cool-season grasses, and switchgrass extended to more than 1.5 m in depth, with switchgrass
roots being more widely distributed in deeper horizons. Root density was significantly greater under switchgrass and cool-season
grasses than under corn or soybean. Soil respiration rates, which ranged from 1.4--7.2 g C m-2 day-1, were up to twice as high under the poplar, switchgrass and cool-season grasses as in the cropped fields. Abundant fine roots,
deep rooting depths, and high soil respiration rates in the multispecies riparian buffer zones suggest that these buffer systems
added more organic matter to the soil profile, and therefore provided better conditions for nutrient sequestration within
the riparian buffers.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献