scholarly journals Root distribution of Acacia mangium Willd. and Macaranga tanarius L. of rainforest

2015 ◽  
Vol 43 (2) ◽  
pp. 141-145 ◽  
Author(s):  
Nazi Avani ◽  
Habibah Lateh ◽  
Ghassem Habibi Bibalani

The number of roots and root area ratio (RAR) decreased with depth in Acacia mangium and Macaranga tanarius and the maximum value of RAR and root number were observed in the first layer of soil. This process was regular in Acacia mangium Willd., but the RAR value showed great variability in Macaranga tanarius L. as the RAR decreased with depth until the second layer (20 cm) and increased again. About 35% of all roots in A. mangium, and about 50% of all roots in M. tanarius are located in the first layer. About 87% of all roots were in the fine root diameter class (d < 2 mm) in M. tanarius species. However 90% of all roots were in the fine root diameter class in A. magnium species. Fine roots contribution to soil reinforcement due to concentration on upper levels, prevent surface erosion and shallow landslide. These results will be useful for slope stability projects. DOI: http://dx.doi.org/10.3329/bjb.v43i2.21665 Bangladesh J. Bot. 43(2): 141-145, 2014 (September)

2018 ◽  
Vol 28 (5) ◽  
pp. 629-636 ◽  
Author(s):  
Matthew B. Bertucci ◽  
David H. Suchoff ◽  
Katherine M. Jennings ◽  
David W. Monks ◽  
Christopher C. Gunter ◽  
...  

Grafting of watermelon (Citrullus lanatus) is an established production practice that provides resistance to soilborne diseases or tolerance to abiotic stresses. Watermelon may be grafted on several cucurbit species (interspecific grafting); however, little research exists to describe root systems of these diverse rootstocks. A greenhouse study was conducted to compare root system morphology of nine commercially available cucurbit rootstocks, representing four species: pumpkin (Cucurbita maxima), squash (Cucurbita pepo), bottle gourd (Lagenaria siceraria), and an interspecific hybrid squash (C. maxima × C. moschata). Rootstocks were grafted with a triploid watermelon scion (‘Exclamation’), and root systems were compared with nongrafted (NG) and self-grafted (SG) ‘Exclamation’. Plants were harvested destructively at 1, 2, and 3 weeks after transplant (WAT), and data were collected on scion dry weight, total root length (TRL), average root diameter, root surface area, root:shoot dry-weight ratio, root diameter class proportions, and specific root length. For all response variables, the main effect of rootstock and rootstock species was significant (P < 0.05). The main effect of harvest was significant (P < 0.05) for all response variables, with the exception of TRL proportion in diameter class 2. ‘Ferro’ rootstock produced the largest TRL and root surface area, with observed values 122% and 120% greater than the smallest root system (‘Exclamation’ SG), respectively. Among rootstock species, pumpkin produced the largest TRL and root surface area, with observed values 100% and 82% greater than those of watermelon, respectively. These results demonstrate that substantial differences exist during the initial 3 WAT in root system morphology of rootstocks and rootstock species available for watermelon grafting and that morphologic differences of root systems can be characterized using image analysis.


2005 ◽  
Vol 21 (5) ◽  
pp. 529-540 ◽  
Author(s):  
Waldemar Zangaro ◽  
Fabio Rodrigo Nishidate ◽  
Flavia Regina Spago Camargo ◽  
Graziela Gorete Romagnoli ◽  
Julia Vandressen

The relationships between arbuscular mycorrhizal fungi and root morphological characteristics were studied under greenhouse conditions of 78 tropical native woody species and 47 seedling species collected in the field. Seedlings of native woody pioneer and early secondary species that generally exhibited fine roots with a dense cover of long root hairs showed higher mycorrhizal response and root mycorrhizal colonization than late-secondary and climax species with coarse roots with a sparse cover of short root hairs. Root-hair length and incidence decreased with the progression among the successional groups while fine-root diameter increased, both in the greenhouse and in the field. The mycorrhizal response was highly correlated to root mycorrhizal colonization in the greenhouse and in the field. These parameters were inversely correlated with the seed mass and fine-root diameter, but directly correlated with root-hair incidence, both in the greenhouse and in the field. Mycorrhizal response and root mycorrhizal colonization were also directly correlated with the root-hair length and root/shoot ratio of uninoculated plants. The seedling mycorrhizal status of the early successional woody species suggests that the root traits of these fast-growing species can be more receptive to attraction, infection and colonization by arbuscular mycorrhizas than root traits of late-successional species.


HortScience ◽  
1990 ◽  
Vol 25 (9) ◽  
pp. 1064e-1064 ◽  
Author(s):  
Edward F. Gilman ◽  
Michael E. Kane

Shoot and root growth were measured on Chinese juniper (Juniperus chinensis L.) Var. `Torulosa', `Sylvestris', `Pfitzeriana' and `Hetzii' 1, 2 and 3 years after planting into a simulated landscape from 10-liter black plastic containers. Mean diameter of the root system increased quadratically averaging 1, 2 m/year; whereas, mean branch spread increased at 0, 33 m/year, Three years after planting, root spread was 2, 75 times branch spread and roots covered an area 5.5 times that covered by the branches. Percentage of total root length located within the dripline of the plants remained fairly constant (71-77%) during the first 3 years following planting. Root length density per unit area increased over time but decreased with distance from the trunk. In the first 2 years after planting shoot weight increased faster than root `weight. However, during the third year after planting, the root system increased in mass and size at a faster rate than the shoots. Root length was correlated with root weight within root-diameter classes, Root spread and root area were correlated with trunk area, branch spread and crown area.


2019 ◽  
Vol 17 (1-2) ◽  
pp. 52-65
Author(s):  
MN Sarkar ◽  
AKMZ Hossain ◽  
SN Islam ◽  
S Shahanaz ◽  
MZ Tareq

An experiment was conducted at the growth chamber of Department of Crop Botany in the Bangladesh Agricultural University, Mymensingh, Bangladesh during March 2018 to observe morpho-physiology and anatomical response of sorghum. Six genotypes were grown in hydroponics with a full nutrient solution (NH4NO3-500 μM; Ca(NO3)2-500 μM; MgSO4-200 μM; KH2P04 -100 μM; FeC13-2μM; H2B03-11 μM; MnC12-2μM; ZnC12-0.35μM; CuCl2-0.2μM; (NH4)6Mo704-0.1 μM) and 100 mM salinity was imposed on 14 days seedlings. Data on morpho-physiological and anatomical parameters from seedlings were collected after 21 days and stress tolerant indexes of shoot and root were analyzed. Anatomical parameters like metaxylem and protoxylem thickness were also investigated. The results indicated that all the parameters viz. root length, shoot length, fresh and dry weight of shoot and root, stress tolerance index of root, and shoot, dry weight of shoot and root, relative chlorophyll content, photochemical efficiency (Fv/Fm), proline concentration, total root area, vascular cylinder area and root diameter were decreased with increasing salinity levels except leaf proline content. Genotypes BD 750 and BD 686 showed better performance considering tolerant indicators while the poor performance was exhibited by BD 747 and BD 753. Thus, based on overall observation BD 750 and BD 686 might be salt tolerant. The Agriculturists 2019; 17(1-2) 52-65


2008 ◽  
Vol 38 (1) ◽  
pp. 92-100 ◽  
Author(s):  
Rock Ouimet ◽  
Claude Camiré ◽  
Marcel Brazeau ◽  
Jean-David Moore

Estimates of belowground biomass and mineralomass are fundamental to understanding carbon and element cycling in forest ecosystems. At two sites, we measured coarse root (diameter ≥2 mm) biomass by diameter class and their mineralomass for sugar maple ( Acer saccharum Marsh.), black spruce ( Picea mariana (Mill.) BSP), and jack pine ( Pinus banksiana Lamb.) trees to relate them to stem diameter at breast height (DBH). All regressions describing coarse root biomass and nutrient content as a function of stem DBH were highly significant (r2 ≥ 0.89, P < 0.001). Root mineral element (N, P, K, Ca, Mg, and S) concentrations varied with tree species and root diameter class. Sugar maple roots had higher N, P, and S concentrations than the other two tree species. Black spruce had higher root Ca concentrations. Element concentrations increased consistently with the reduction of root diameter for the three studied species. We also found that the horizontal root extent of sugar maple was related to tree DBH. In conjunction with other studies, the relationship suggests that this tree species could tolerate a 10%–20% root loss but not losses ≥28%–34%; otherwise, sugar maple health and vigour would be compromised in the short term.


2009 ◽  
Vol 6 (3) ◽  
pp. 3993-4033 ◽  
Author(s):  
F. Preti ◽  
F. Giadrossich

Abstract. The present paper deals with the characteristics of the root system of Spanish Broom (Spartium junceum L.), a species that is worth taking into consideration for its capacity for adaptation and resistance to drought. In particular, the aims of the study were 1) to investigate the plant's bio-mechanical aspects and 2) to verify whether root reinforcement and the field rooting ability of stem cuttings enhance its potential for use in slope stabilization and soil bio-engineering techniques, particularly in Mediterranean areas. Single root specimens were sampled and tested for tensile strength, obtaining classical tensile strength-diameter relationships. Analyses were performed on the root systems in order to assess root density distribution. The Root Area Ratio (RAR) was analyzed by taking both direct and indirect measurements, the latter relying on image processing. The data obtained were used to analyze the stability of an artificial slope (landfill) and root reinforcement. The measurement and calculation of mean root number, mean root diameter, RAR, root cohesion and Factor of safety are presented in order to distinguish the effect of plant origin and propagation. Furthermore, tests were performed to assess the possibility of agamic propagation (survival rate of root-ball endowed plants, rooting from stem cuttings). These tests confirmed that agamic propagation is difficult, even though roots were produced from some buried stems, and for practical purposes it has to be ruled out. Our results show that Spanish Broom has good bio-mechanical characteristics with regard to slope stabilization, even in critical pedoclimatic conditions and where inclinations are quite steep, and it is effective on soil depths of up to about 50 cm, in agreement with other studies on Mediterranean species. It is effective in slope stabilization, but less suitable for soil bio-engineering or for triggering natural plant succession.


2009 ◽  
Vol 36 (1) ◽  
pp. 11 ◽  
Author(s):  
Dirk Gaul ◽  
Dietrich Hertel ◽  
Christoph Leuschner

The importance of root systems for C cycling depends crucially on fine root longevity. We investigated mean values for fine root longevity with root diameter, root C/N ratio and soil depth using radiocarbon (14C) analyses in a temperate Norway spruce [Picea abies (L.) Karst.] forest. In addition, we applied sequential soil coring and minirhizotron observations to estimate fine root longevity in the organic layer of the same stand. The mean radiocarbon age of C in fine roots increased with depth from 5 years in the organic layer to 13 years in 40–60 cm mineral soil depth. Similarly, the C/N ratios of fine root samples were lowest in the organic layer with a mean value of 24 and increased with soil depth. Roots >0.5 mm in diameter tended to live longer than those being <0.5 mm in diameter. By far the strongest variability in fine root longevity estimates was due to the chosen method of investigation, with radiocarbon analyses yielding much higher estimates (5.4 years) than sequential soil coring (0.9 years) and minirhizotron observations (0.7 years). We conclude that sequential soil coring and minirhizotron observations are likely to underestimate mean fine root longevity, and radiocarbon analyses may lead to an overestimation of mean root longevity.


Sign in / Sign up

Export Citation Format

Share Document