Variation in Number of Resin Canals per Needle in Pond Pine

1963 ◽  
Vol 124 (4) ◽  
pp. 251-253 ◽  
Author(s):  
John B. White ◽  
H. O. Beals
Keyword(s):  
IAWA Journal ◽  
1998 ◽  
Vol 19 (2) ◽  
pp. 181-189 ◽  
Author(s):  
Keiko Kuroda

Trunks of Chamaecyparis obtusa were injured to examine seasonal differences in traumatic resin canal formation in secondary phloem. Even after wounding during winter, differentiation of axial parenchyma into epithelium was initiated, and vertical resin canals formed. After winter wounding, resin canal development was slower and the tangential extent of resin canals was narrower than after spring wounding, and it took one to two months until resin secretion began. After spring wounding, the sites of resin canal formation were the 1- and 2-year-old annual rings of phloem. In August, the location of resin canal formation shifted into the current and 1-year-old annual ring. Resin canals never formed in secondary phloem areas that were 3 or more years old. In C. obtusa trunks that are affected by the resinous stem canker, numerous tangentiallines of resin canals are found throughout the phloem, not just recent and 1- to 2-year-old phloem. The present research indicates that these many lines of resin canals were not formed at one time, and that the stimuli that induce traumatic resin canals must occur repeatedly over many years. The data on artificial wounding effects are useful for understanding resinous stem canker.


IAWA Journal ◽  
2003 ◽  
Vol 24 (3) ◽  
pp. 257-267
Author(s):  
Alex C. Wiedenhoeft ◽  
Regis B. Miller ◽  
Terra J. Theim

Three microscopic characters were evaluated for the identification of Pinus contorta and Pinus ponderosa. The tangential diameter of the resin canals, including the epithelium, was compared to the tangential diameter of the entire resin canal complex. The latter measurement was shown to give diagnostic results for these species. Data from the examination of ray composition do not support previously published methods for separating P. contorta and P. ponderosa. The presence or absence of small elongate crystals in the subsidiary parenchyma of the resin canal complexes was shown to be the most powerful diagnostic character for separating the wood of these species.


Author(s):  
Vladimír Gryc ◽  
Petr Horáček

The paper was aimed at the determination of variability of horizontal resin canal dimension in spruce wood in relation to the position in a spruce stem. Significant changes of dimensions in horizontal resin canal along the stem length and radius were found. On the basis obtained of results 3D models (for CW, OW, SWL and SWP zones) describing changes in resin canal dimensions in spruce in relation to the position in a stem were created. In the models, the resin canal dimension decreases with the height of a stem and on the other hand, with an increasing distance from the stem pith the dimension of resin canal increases. The importance of the paper consists in the enlargement of findings about the structure of spruce with compression wood.


2014 ◽  
Vol 63 (1) ◽  
pp. 67-76 ◽  
Author(s):  
Maria A. Bobowicz ◽  
Adolf F. Korczyk

Two-year old needles were collected from 272 standing trees of <i>Pinus sylvestris</i> L., representing 8 Polish populations. The needles were studied in respect to IS morphological and anatomical traits. The obtained data were subjected to multivariate statistical analysis in an attempt to delineate interpopulational variability. Multivariate analysis of variance with testing of statistical hypotheses and discriminant analysis were conducted. Mahalanobis distances were calculated between each of population in pairs and their significance was estimated using Hotelling T<sup>2</sup> statistics. On the basis of the shortest Mahalanobis distances a minimum spanning tree was constructed and on the basis of Euklidean distances hierarchy grouping was performed. A large majority of the populations was found to differ significantly from the remaining populations. The population from Bolewice proved to be most divergent. The principal variables which proved capable of discriminating between populations were found to include: needle length, the number of stomata on the flat side of the needle and the number of resin canals. Using Bryant's test, the studied populations were found to belong to two geographic groups: the North-Polish one or the South-Polish one.


1934 ◽  
Vol 10 (2) ◽  
pp. 129-136
Author(s):  
J. B. Prince
Keyword(s):  

Forests ◽  
2020 ◽  
Vol 11 (3) ◽  
pp. 265
Author(s):  
Joana M.S. Cardoso ◽  
Luís Fonseca ◽  
Isabel Abrantes

The pinewood nematode (PWN) Bursaphelenchus xylophilus, the causal agent of the pine wilt disease (PWD), enters above-ground parts of the tree, migrates through the resin canals and feeds on plant cells causing extensive damage. In order to penetrate the cell wall and establish a parasitic relationship with host trees, the PWN needs to secretea mixture of active cell wall degrading enzymes. In maritime pine, Pinus pinaster, which is high susceptible to PWN, xyloglucan is the major hemicellulosic polysaccharide in primary cells. The xyloglucan backbone is susceptible to hydrolysis by numerous endoglucanases, some of them specific to xyloglucan. However, to completely degrade xyloglucan, all substitutions on the glucan backbones must be released, and l-fucose residues in xyloglucan branches are released by α-l-fucosidases. In the present study, the molecular characterization of two α-l-fucosidases found in PWN secretome was performed. Moreover, a novel α-l-fucosidase was identified and its cDNA and gene sequence were determined. The three-dimensional structures of these α-l-fucosidases were predicted and the transcript levels were analyzed, thus providing new insights into fundamental PWN biology and the possible role of these proteins as cell wall degrading enzymes.


Ecology ◽  
1958 ◽  
Vol 39 (1) ◽  
pp. 33 ◽  
Author(s):  
Ben F. Graham ◽  
Allen L. Rebuck
Keyword(s):  

2001 ◽  
Vol 79 (11) ◽  
pp. 1257-1261 ◽  
Author(s):  
Jinxing Lin ◽  
D A Sampson ◽  
R Ceulemans

Resin canals are an important taxonomic characteristic in conifers. In this paper we examined within- and between-needle variation of the cross-sectional number of resin canals in Scots pine (Pinus sylvestris L.). Variation within needles was determined from 12 free-hand sections taken along the whole length of foliage collected from a common crown position. The effect of crown location and tree age on resin-canal density was also examined from the midpoint cross sections of 450 Scots pine needles collected from interior and exterior locations from the top, middle, and bottom of 25 crowns of trees ranging in age from 8 to 70 years. Within-needle resin-canal density varied with needle length. Two resin canals were typical for the basal and the terminal needle cross sections. There were 3.2 and 8.6 resin canals for cross sections taken from 10 and 30% of the needle length from the basal sheath, respectively. Resin-canal density was largest, and relatively constant, between 30 and 80% of the needle length. We found significant differences in the cross-sectional number of needle resin canals, as influenced by crown positions and tree age. Resin-canal density increased with foliage height. Foliage from the top one-third of crowns had significantly more resin canals than foliage from the bottom. Foliage collected from the crown interior (proximal to the stem) had fewer resin canals than samples from the crown edge. Resin-canal density increased from 7.1 to 10.3 as tree age increased from 8 to 70 years. These results suggest that crown position and tree age need to be incorporated into the sampling protocols used to establish species standards in resin-canal density, at least for Scots pine, if meaningful comparisons are to be made.Key words: resin canal, needle age, crown position, needle anatomy, Pinus sylvestris.


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