Black stem galls on aspen: anatomy and histochemistry

1995 ◽  
Vol 73 (3) ◽  
pp. 391-412 ◽  
Author(s):  
Patricia E. Crane ◽  
P.V. Blenis ◽  
Y. Hiratsuka

Large black stem galls occur sporadically on trembling aspen (Populus tremuloides) in western Canada. Although little is known about their cause or structure, trees having these galls are less likely than surrounding aspen to have advanced decay caused by the fungus Phellinus tremulae. The anatomy and histochemistry of black galls and associated branch galls were studied and compared with normal wood and bark. Light microscopy showed that the cambium of black galls produces greater numbers of cells per growth ring and that growth rings are two to three times wider than normal. Vessel elements and fibers are unusually small and misshapen. Gall xylem has characteristics associated with wounding or infection: ray cells filled with phenolic deposits, and vessel elements occluded by tyloses and granular material. Frequent radial strands of undifferentiated callus tissue surrounded by necrophylactic periderms indicate sites of cambial damage of unknown cause. White areas within dark-colored gall xylem of some samples were free of most of these abnormalities, suggesting that a persistent agent is required for continuing tumor growth. Thickened outer bark harbored a variety of saprophytic fungi, especially hyphomycetes. Surface and internal morphology of black galls was also compared with similar stem galls caused by poplar budgall mites (Aceria parapopuli) and was found to be different. Bacteria, fungi, or mites were not obvious within living tissue, and further studies are necessary to determine the etiology of black galls. Key words: Populus tremuloides, poplar, black gall, wood anatomy.

IAWA Journal ◽  
2005 ◽  
Vol 26 (4) ◽  
pp. 469-476 ◽  
Author(s):  
Sezgin K. Gülsoy ◽  
Hüdaverdi Eroğlu ◽  
Nesime Merev

Chemical and anatomical properties of tumorous and normal wood of Quercus robur L. subsp. robur were compared. Tumorous growth appeared as a result of topping stress. Orientation of cells was severely disrupted in the affected wood. In cross section, aspects of cells changed abruptly from transverse to longitudinal, and in tangential section all wood elements appeared to turn around each other like a fingerprint. Vessel elements and fibres of affected wood were shorter than those of healthy wood. The vessels of affected wood were smaller in diameter especially in the earlywood. On the other hand, multiseriate ray height was shorter than that of normal wood. In addition, perforated ray cells occurred. The ray and axial parenchyma cells of tumorous wood contained dark coloured phenolic compounds. Normal wood had calcium oxalate crystals, while tumorous wood did not. Chemical analyses showed that hemicellulose content and solubility rates in 1% NaOH, cold water, hot water, and alcohol- benzene were higher than those of normal wood. Cellulose and ash contents of tumorous wood were slightly lower than in normal wood. In addition, air-dry specific gravity of tumorous wood was higher than that of normal wood.


IAWA Journal ◽  
1999 ◽  
Vol 20 (4) ◽  
pp. 395-404 ◽  
Author(s):  
Tetsuo Itabashi ◽  
Shinso Yokota ◽  
Nobuo Yoshizawa

Septate wood fibers were abundant in the following parts of growth rings of Kalopanax pictus Nakai: 1) around the vessels, 2) in the vicinity of ray cells, 3) in terminal regions of the growth rings. Septum formation in wood fibers progressed from the initial region (pore zone) towards the terminal region within a current growth ring with progressing 1ignification of the wood fiber walls. Many septate wood fibers at the end of the growth ring had radially continuous septa. Karyokinesis was observed in severa1 wood fibers before the initiation of septum formation, while lignification was in progress after the completion of the S3 layer deposition. This suggests that the septation starts in parallel with the progress of lignification after the deposition of the S3 layer.


IAWA Journal ◽  
2003 ◽  
Vol 24 (4) ◽  
pp. 411-420 ◽  
Author(s):  
Kishore S. Rajput ◽  
K.S. Rao

Development of cambial variant and xylem structure were studied in the stem of Cocculus hirsutus (Menispermaceae). In the early stages of stem development several collateral vascular bundles are joined by interfascicular cambium resulting in the formation of a complete cambial cylinder. After functioning for two to three years the cambial ring ceases its activity. Subsequently a second ring of cambium is formed from the innermost cortical parenchyma cells. These parenchyma cells undergo periclinal divisions to give rise to cells that become lignified, abaxially, and cambial cells, adaxially. The cambial cells divide periclinally giving rise to individual vascular bundles with xylem and phloem. Later the cambium in each bundle is joined by interfascicular cambium. Subsequent cambia develop similarly resulting in the formation of successive rings of xylem and phloem. During the leafless condition, all the cambial rings are dormant, and flanked by mature xylem and phloem elements. With the sprouting of new leaves, either the existing outermost cambium reactivates or an entire new ring of cambium develops. The xylem is diffuseporous with indistinct growth rings. It is composed of fibre-tracheids, tracheids, vessel elements, libriform fibres, and parenchyma cells. Xylem rays are multiseriate, compound and heterocellular. Deformed libriform fibres and vessel elements commonly occur among the ray cells in all the successive rings of xylem. The length of fibres and the height and width of xylem rays increase gradually from the centre towards the periphery of the stem.


IAWA Journal ◽  
1994 ◽  
Vol 15 (2) ◽  
pp. 149-155 ◽  
Author(s):  
Young Geun Eom ◽  
Youn Jib Chung

The anatomy of tumor wood and normal wood in a branch of Korean red pine (Pinus densiflora S. et Z.) is compared. In tumor wood the tracheids and rays are irregularly arranged, the cell lumina contain resinous substances and fungal hypha, the tracheid files are of variable width within the growth ring, and traumatic vertical resin canals are present. There are also differences in length of tracheids, numbers of vertical and horizontal resin canals (fusiform rays), height of fusiform rays, and number and height of uniseriate rays. The modified structure of the tumor wood originates near the pith. The wider growth rings, considerably shorter but not wider tracheids, and larger and more numerous rays in tumor wood are associated with a higher radial growth rate, which in turn results in the externally massive wood tumor.


1951 ◽  
Vol 29 (2) ◽  
pp. 147-157 ◽  
Author(s):  
T. C. Vanterpool ◽  
Ruth Macrae

The Canadian tuckahoe is the perennial sclerotium of Polyporus tuberaster jacq. ex Fries. It is commonly found in the parkland belt of the Canadian prairies where land supporting, virgin poplar groves, mainly Populus tremuloides Michx., is being brought under cultivation. Sporophore as many as three to a single sclerotium, appear in late June and July. Interfertility studies with single spore cultures isolated from sporophores derived from four sources in Western Canada and from one source in Italy have shown that both the Canadian fungus and the European P. tuberaster are heterothallic, have the tetrapolar type of interfertility, and are interfertile.


1986 ◽  
Vol 16 (5) ◽  
pp. 1041-1049 ◽  
Author(s):  
K. C. Yang ◽  
C. A. Benson ◽  
J. K. Wong

The distribution and vertical variation of juvenile wood was studied in an 81-year-old dominant tree and an 83-year-old suppressed tree of Larixlaricina (Du Roi) K. Koch. Two criteria, growth ring width and tracheid length, were used to demarcate the boundary of juvenile wood. The width of juvenile wood, expressed in centimetres and the number of growth rings, decreased noticeably from the base to the top of the tree. The volume of juvenile wood decreased in a similar pattern. These decreasing trends had a strong negative correlation with the year of formation of cambial initials at a given tree level. The length of these cambial initials decreased with increasing age of formation of the cambial initials. In the juvenile wood zone, there was a positive linear regression between the growth ring number (age) and the tracheid length. The slopes of these regression lines at various tree levels increased as the age of the year of formation of the cambial initials increased. At a given tree level, the length of tracheids increased from the pith to a more uniform length near the bark. However, the number of years needed to attain a more uniform tracheid length decreased from the base to the top of the tree. These relationships suggest that the formation of juvenile wood is related to the year of formation of the cambial initials. Consequently, the juvenile wood is conical in shape, tapering towards the tree top.


1983 ◽  
Vol 5 (5) ◽  
pp. 161
Author(s):  
José Newton Cardoso Marchiori

This paper deals with the description of general, macroscopic and microscopic anatomy of Colletia paradoxa (Spreng.) Escalante, an aphyllous and xerophilous shrub from Rio Grande do Sul (Brazil). Pores of very small diameter, very short vessel elements, spiral thickenings and simple perforation plates in vessels, non sptate libriform fibers, scanty paratracheal axial paranchyma, and Heterogeneous II rays were observed in the wood.. Perforated cells are also common in rays. The presence of perforated ray cells and anatomical features of the vessel elements are discussed with respect to eco-physiological aspect of the plant and wood anatomy literature.


2004 ◽  
Vol 155 (6) ◽  
pp. 208-212 ◽  
Author(s):  
Peter Bebi ◽  
Alejandro Casteller ◽  
Andrea Corinna Mayer ◽  
Veronika Stöckli

Snow, avalanches, and permafrost are extreme site conditions for plants. Reactions and adaptations to such extreme conditions can be reconstructed with growth ring analysis and linked with corresponding climate and disturbance data. On the basis of five case studies in and around the long-term research site Stillberg, near Davos, we discuss both the potential and the limits of dendroecology to understand the effect of such extreme site conditions. Despite some uncertainties in reliably assigning plant reactions, growth ring analysis is a valuable addition to better understand the effects of extreme site conditions on the survival and growth of plants. This can lead to improved management strategies associated with natural hazards, especially in the case of avalanches.


2016 ◽  
Vol 25 (10) ◽  
pp. 1086 ◽  
Author(s):  
Kellie A. Uyeda ◽  
Douglas A. Stow ◽  
John F. O'Leary ◽  
Christina Tague ◽  
Philip J. Riggan

Chaparral wildfires typically create even-aged stands of vegetation that grow quickly in the first 2 decades following a fire. Patterns of this growth are important for understanding ecosystem productivity and re-establishment success, but are logistically challenging to measure over long time periods. We tested the utility of a novel method of using shrub growth rings to estimate stand-level biomass accumulation at an annual time scale in southern California chaparral. We examined how temporal variation in precipitation and spatial variation in solar irradiation influence that accumulation. Using field measurements and a relationship between stem basal area and aboveground biomass, we estimated current biomass levels in an 11-year-old chaparral stand, and used growth-ring diameters to estimate growth in each year from age 4 to 11 years. We found that annual growth as measured by shrub growth rings tracked closely with patterns of annual precipitation, but not with time since fire. Solar irradiation was not found to be a significant covariate with total biomass by plot, possibly due to sampling area limitations. The close relationship of annual biomass accumulation with annual precipitation indicates that shrub growth-ring measurements can provide a useful metric of stand-level recovery.


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