Determination of fiber length and juvenile and mature wood zones from Hevea brasiliensis trees grown in Brazil

2010 ◽  
Vol 69 (4) ◽  
pp. 659-662 ◽  
Author(s):  
A. L. Ferreira ◽  
E. T. D. Severo ◽  
F. W. Calonego
Keyword(s):  
Hevea Brasiliensis ◽  
Fiber Length ◽  
Mature Wood

Determination of fiber length and juvenile and mature wood zones in Acer velutinum Boiss. trees grown in Iran

2012 ◽  
Vol 14 (4) ◽  
pp. 323-326 ◽  
Author(s):  
Majid Kiaei ◽  
Reza Bakhshi ◽  
Samane Veylaki
Keyword(s):  
Fiber Length ◽  
Mature Wood

scholarly journals ANATOMICAL CHARACTERIZATION OF TENSION WOOD IN Hevea brasiliensis (Willd. ex A. Juss.) Mull. Arg.

2016 ◽  
Vol 40 (6) ◽  
pp. 1099-1107
Author(s):  
Letícia Maria Alves Ramos ◽  
João Vicente de Figueiredo Latorraca ◽  
Thayanne Caroline Castor Neto ◽  
Letícia Souza Martins ◽  
Elias Taylor Durgante Severo
Keyword(s):  
Hevea Brasiliensis ◽  
Fiber Length ◽  
Tension Wood ◽  
Rubber Tree ◽  
Microfibril Angle ◽  
Vessel Diameter ◽  
Longitudinal Distribution ◽  
Axial Parenchyma ◽  
Gelatinous Fibers ◽  
Gelatinous Fiber

ABSTRACT Tension wood is an important anatomical structure for its participation in the orientation of the trunk and the architecture of the branches as a function of structural reinforcement. However, its presence in large amounts significantly affects the technological properties of wood, just as in the rubber tree. Nevertheless, there is still demand for information about the origin, distribution and structural features in this species. Thus, this study aims to characterize the cellular structures in tension and opposite wood in Hevea brasiliensis (rubber tree), as well as its radial and longitudinal distribution. Discs at the base and the middle of the commercial logs were collected from three trees in a commercial plantation located in Tabapoã - SP. Tangential diameter of vessels, fiber length (gelatinous and non-gelatinous fibers), microfibril angle and proportionality of cellular elements (vessels, axial parenchyma, ray, gelatinous fibers and non-gelatinous fibers) were measured, and influence of gelatinous fiber presence in vessel diameter was observed. Gelatinous fibers were observed in the two types of wood and in the two trunk heights. Both types of wood were distinguished by gelatinous fiber length and the proportion of axial parenchyma. The tension wood in mid-trunk was the most different, with long gelatinous fibers and less abundant, larger vessel diameter and vessel proportion. Moreover, smaller vessel diameter was observed in the regions with a high proportion of gelatinous fibers, suggesting that the plant invests more support than in liquid transport.

scholarly journals Determination of the Influence of Cultural Techniques "Densities and Opening Standardʺ on Agrophysiological Parameters of Clones Pb 260, Irca 111 and Rrim 703

2021 ◽  
pp. 31-39
Author(s):  
Diarrassouba Moussa ◽  
Soumahin Eric Francis ◽  
Konan Djézou ◽  
N’guessan Kan Pulchérie ◽  
Moro Affia Perpetue ◽  
...  
Keyword(s):  
Experimental Design ◽  
Hevea Brasiliensis ◽  
Normal Density ◽  
Low Density ◽  
Annual Increase ◽  
Rubber Plantations ◽  
Average Annual Increase ◽  
Sustainable Improvement ◽  
Cultivation Techniques

To find out the effect of cultural techniques on agrophysiological parameters, four combinations ̏planting densities (low density or DF at 350 t/ha, normal density or DN at 510 t/ha) and opening standards (opening at 65cm and opening at 50 cm) ̋ were tested on Hevea brasiliensis clones PB 260, IRCA 111 and RRIM 703. This study was conducted for nine years with a split-plot experimental design of two treatments and two subtreatments repeated three times. The different combinations of treatments and subtreatments tested were low density (DN-50 cm), low density (DN-65 cm), normal density (DF-50 cm), normal density (DF- 65 cm). The parameters evaluated were the production at bleeding and per hectare, the average annual increase in circumference, the rate of tree losses and the rate of trees with dry notches. Production per tree was significantly higher at 350 t/ha and 65 cm opening (DF-65 cm), while per hectare production was higher at 510 t/ha. The girths of the different clones are stronger at DF and at the 65 cm opening. The rate of tree loss and the rate of trees with dry notch were low at the 510 t/ha density and the 65cm opening. The appropriate density and opening standard was "normal density 510 t/ha and opening to circumference 50 cm". The cultivation techniques especially the density and opening standard judiciously applied can participate in the sustainable improvement of rubber productivity of rubber plantations.

Spectrographic Determination of Calcium in Latex of Natural Rubber (Hevea Brasiliensis)

1970 ◽  
Vol 24 (6) ◽  
pp. 583-587 ◽  
Author(s):  
S. K. Ng ◽  
R. C. H. Hsia ◽  
P. T. Lai
Keyword(s):  
Natural Rubber ◽  
Atomic Absorption ◽  
Hevea Brasiliensis ◽  
Internal Standard ◽  
Lithium Carbonate ◽  
Cathode Layer ◽  
Spectrographic Determination ◽  
Dc Arc

A cathode layer dc arc method of determining microgram amounts of calcium in latex of Hevea brasiliensis is described. Using lithium carbonate and lanthanum sulphate as buffers, a working curve covering 0.032% to 10.0% Ca in ash of latex can be constructed with palladium as internal standard. Phosphate and silica suppress Ca emission but silica has a considerably greater effect. Of the four matrices examined, the composition with 44.7% K2O, 22.3% P2O5, and 13.4% MgO, which is most representative of the composition of latex ash, gives reproducible Ca values and these are in closest agreement with those obtained by atomic absorption. The spectrographic technique may be extended to simultaneously determine trace amounts of Mn, Fe, Cu, and Si.

scholarly journals Automatic Determination of Fiber-Length Distribution in Composite Material Using 3D CT Data

2010 ◽  
Vol 2010 (1) ◽  
Author(s):  
Matthias Teßmann ◽  
Stephan Mohr ◽  
Svitlana Gayetskyy ◽  
Ulf Haßler ◽  
Randolf Hanke ◽  
...  
Keyword(s):  
Composite Material ◽  
Fiber Length ◽  
Length Distribution ◽  
3D Ct ◽  
Automatic Determination ◽  
Fiber Length Distribution ◽  
Ct Data
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