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IAWA Journal - Volume 32(3)

|Author(s): |Barbara Lachenbruch |

|Title: |Physical Models as an Aid for Teaching Wood Anatomy |

|Source: |IAWA Journal, Volume 32, Issue 3 |

|Publication Year: |2011 |

|Pages: |301-312 |

|Keywords: |physical models; classroom; Teaching wood anatomy |

|Abstract: |Student activities and instructor-made models are described to facilitate and encourage other |

| |instructors to develop their own appropriate activities and models for teaching the |

| |three-dimensional structure of wood. The teaching activities include making several annual rings|

| |with straws pushed into clay, drawing wood’s structure onto a piece of paper that is folded to |

| |resemble a wedge, and assigning students to make an anatomical model to present in class. Plans |

| |are given for instructor-made models (1:500 scale) of tracheids, vessel elements, and a hardwood|

| |‘fiber’ to demonstrate their relative dimensions and geometries. These models also include a set|

| |of outerwood and corewood tracheids onto which the microfibril angle is traced, and one tracheid|

| |on which bordered and cross-field pitting are shown. Plans are then given for a bordered pit |

| |pair with its membrane (1:6300 scale). The last model demonstrates the Hagen-Poiseuille equation|

| |with an array of 16 conduits that together have the same potential flow as one conduit of two |

| |times their diameter. The use of these models has enlivened the classroom and helped students to|

| |more readily grasp wood anatomy and function. |

|DOI: |10.1163/22941932-90000059 |

|Author(s): |Anna Wilczek; Joanna Jura-Morawiec; Paweł Kojs; Muhammad Iqbal; Wiesław Włoch |

|Title: |Correlation of intrusive growth of cambial initials to rearrangement of rays in the vascular |

| |cambium |

|Source: |IAWA Journal, Volume 32, Issue 3 |

|Publication Year: |2011 |

|Pages: |313-331 |

|Keywords: |ray initials; intrusive growth; fusion of rays; splitting of rays; Vascular cambium |

|Abstract: |It is well documented that apical elongation of fusiform cambial initials through extension of |

| |their longitudinal edges, and their intrusion between tangential walls of the neighbouring |

| |initials and their closest derivatives cause rearrangement of fusiform cells, without increasing|

| |the cambial circumference. However, the concurrent rearrangement of rays is not fully |

| |understood. This study deals with Pinus sylvestris L., Tilia cordata Mill. and Hippophaë |

| |rhamnoides L., possessing a nonstoreyed, storeyed and double-storeyed type of cambium, |

| |respectively, and shows that the mechanism for rearrangement of ray initials is similar to the |

| |one proposed for fusiform initials, and includes multiplication of ray initials by anticlinal |

| |divisions, intrusive growth of ray initials, elimination of ray initials caused by intrusive |

| |growth of neighbouring fusiform initials, and transformation of ray initials into fusiform |

| |initials. Intrusive growth of a ray initial does not necessarily lead to the formation of a new |

| |fusiform initial, as it is dependent on the extent of the intrusive growth taken place. The |

| |extent of rearrangement of cambial cells is determined by the intensity of events occurring |

| |among the fusiform as well as ray initials. Intrusive growth of these initials does not |

| |influence the size of the cambial circumference. |

|DOI: |10.1163/22941932-90000060 |

|Author(s): |Karumanchi S. Rao; Jong Sik Kim; Yoon Soo Kim |

|Title: |Early changes in the radial walls of storied fusiform cambial cells during fiber differentiation|

|Source: |IAWA Journal, Volume 32, Issue 3 |

|Publication Year: |2011 |

|Pages: |333-340 |

|Keywords: |storied cambium; fiber differentiation; Cell wall changes; beaded cell walls; Holoptelea |

| |integrifolia; fusiform cells |

|Abstract: |There is little information about the ultrastructural changes taking place in the radial walls |

| |of fusiform cambial cells during differentiation into xylem derivatives. The present study |

| |reports the early events occurring in the radial walls of fusiform cambial cells (FCCs) during |

| |fiber elongation in Holoptelea integrifolia, a deciduous tropical tree with storied cambium. |

| |Serial tangential sections of active cambial zone cells demonstrate the initiation of intrusive |

| |cell wall elongation from gabled ends of FCCs during fiber development. The elongation at the |

| |tip is followed by the axial extension of the entire cell. It was evident from ultrastructural |

| |observations made on the tangential sections that the thick beaded pattern on FCC radial walls |

| |disappear following cell elongation. PATAg staining, specific for wall polysaccharides showed |

| |that, initially, the beaded structures undergo wall loosening following hydrolysis of pectic |

| |polysaccharides in the middle lamella. Then the loosened primary walls come together with the |

| |axial extension of cells. Thus the beaded nature disappears in the differentiating cambial |

| |cells. This study highlights the cell wall changes associated with the differentiation of FCCs |

| |into fibers. |

|DOI: |10.1163/22941932-90000061 |

|Author(s): |Ridwan Yahya; Katsuhiko Koze; Junji Sugiyama |

|Title: |Fibre Length in Relation to the Distance from vessels and contact with rays in Acacia Mangium |

|Source: |IAWA Journal, Volume 32, Issue 3 |

|Publication Year: |2011 |

|Pages: |341-350 |

|Keywords: |serial images; fibres; Alignment; rays; vessels |

|Abstract: |Fibre length, as a function of radial or tangential distance from a vessel was estimated from |

| |serial cross sections. This new method is easier and faster than earlier methods which rely on |

| |photographic prints of transverse images for the analysis. When necessary virtual tangential and|

| |radial sections were produced from 3D data to enable fibre length estimation. Fibre length up to|

| |the 5th and 2nd fibres away from a vessel in radial and tangential directions, respectively, |

| |were significantly shorter than fibres at greater distance from the vessels. Fibre length |

| |strongly correlated with radial vessel distance (r = 0.83) up to the 5th fibre and then leveled |

| |off. Vessel-adjacent fibres on the radial or tangential side of a vessel did not significantly |

| |differ in length. However, the rate of length increase differed significantly in the radial and |

| |tangential directions. Percentage of contact with rays varied independently of fibre length. |

|DOI: |10.1163/22941932-90000062 |

|Author(s): |Michelle R. Cleary; Terry Holmes |

|Title: |Formation of traumatic resin ducts in the phloem of western redcedar (Thuja plicata) roots |

| |following abiotic injury and pathogenic invasion by Armillaria ostoyae |

|Source: |IAWA Journal, Volume 32, Issue 3 |

|Publication Year: |2011 |

|Pages: |351-359 |

|Keywords: |Thuja plicata; Armillaria ostoyae; traumatic phloem resin ducts; abiotic wounding; |

| |necrophylactic periderm |

|Abstract: |Anatomical changes involved in traumatic phloem resin duct (TPRD) formation in western redcedar |

| |(Thuja plicata) roots were examined following abiotic wounding and fungal invasion by Armillaria|

| |ostoyae. Following necrophylactic periderm formation, hyperplasia and expansion of a band of |

| |phloem parenchyma cells occurred in close proximity to the vascular cambium and schizogenous and|

| |lysigenous separation of its derivatives resulted in a series of longitudinal resin ducts in the|

| |inner to mid-phloem region. Fungal invasion appeared to amplify traumatic resin duct formation |

| |in the phloem. While traumatic cavities in the phloem have been reported for other Cupressaceae,|

| |this is the first report documenting TPRD formation in western redcedar. |

|DOI: |10.1163/22941932-90000063 |

|Author(s): |Eduardo Luiz Longui; Israel Luiz de Lima; Ivelize Maciel Andrade; Miguel Luiz Menezes Freitas; |

| |Sandra Monteiro Borges Florsheim; Antonio Carlos Scatena Zanatto; Francides Gomes da Silva |

| |Júnior |

|Title: |Seed provenance influences the wood structure of Gallesia Integrifolia |

|Source: |IAWA Journal, Volume 32, Issue 3 |

|Publication Year: |2011 |

|Pages: |361-374 |

|Keywords: |juvenile wood anatomy; provenance; ex situ conservation; radial variation; chemical |

| |constituents; Basic density |

|Abstract: |Plants from three provenances of Gallesia integrifolia were cultivated under homogeneous growth |

| |conditions to determine the effect of seed provenance on the wood density, anatomy and chemical |

| |constituents. In 1981, seeds were collected in Ribeirão Preto (RP), Campinas (CA) and Bauru |

| |(BA). Seedlings of the three provenances were planted at the Luiz Antonio Station in 1982 and |

| |trees were felled in 2008. The plants showed significant differences in their wood, possibly due|

| |to different genotypes. The relatively small vessel diameter in CA was associated with a high |

| |wood density. The provenances RP and CA did not show radial variation in density, which |

| |indicates a more homogeneous wood than BA. To obtain wood with a high density, trees of the |

| |provenance CA would be most useful, while wood from the RP and CA provenances would be suitable |

| |if a homogeneous wood with minor radial variation were desirable. |

|DOI: |10.1163/22941932-90000064 |

|Author(s): |Mauro Bernabei; Jarno Bontadi |

|Title: |Distinguishing root- and stem-wood of Picea Abies |

|Source: |IAWA Journal, Volume 32, Issue 3 |

|Publication Year: |2011 |

|Pages: |375-382 |

|Keywords: |Picea abies Karst; root-wood; wood identification; wood anatomy; Bartholin’s method |

|Abstract: |In archaeology, palaeobotany and dendrochronology, it can be important to distinguish between |

| |root- and stem-wood. Although numerous studies have described the root-wood of various species |

| |in great detail, there is, as yet, no quick and generally accepted wood anatomy-based method to |

| |distinguish Norway spruce root- from stem-wood. This study compared the anatomical |

| |characteristics of Norway spruce root- and stem-wood, and found it was possible to distinguish |

| |these two parts of the tree by differences in the average number of rows of ray tracheids as |

| |viewed in radial section, and in the frequency of rays per mm2 as viewed in tangential section. |

| |The reliability of these criteria was verified in a double-blind trial. Finally, a |

| |cross-comparison between Norway spruce and European larch root- and stem-wood characteristics |

| |was carried out, and it was determined that spruce root-wood can be distinguished from larch |

| |stem- or root-wood. |

|DOI: |10.1163/22941932-90000065 |

|Author(s): |Shuichi Noshiro; Yuka Sasaki |

|Title: |Identification of Japanese species of evergreen Quercus and Lithocarpus (Fagaceae) |

|Source: |IAWA Journal, Volume 32, Issue 3 |

|Publication Year: |2011 |

|Pages: |383-393 |

|Keywords: |identification; Fagaceae; Japan; Lithocarpus; Quercus subg. Cyclobalanopsis; wood structure |

|Abstract: |To identify archaeological oak woods with very large vessels (> 200 μm), the wood structure of |

| |eleven species of evergreen Quercus and Lithocarpus from Japan were studied. Species groups |

| |could be identified by the size and frequency of vessels and the ray structure. Quercus |

| |phillyraeoides of subg. Sclerophyllodrys had semi-ring-porous wood with small (< 100 μm on |

| |average), numerous vessels, and aggregate rays. Two species of Lithocarpus had aggregate to |

| |semi-compound rays that came to be divided by the development of vertical masses of fusiform |

| |cells. Among species of Quercus subg. Cyclobalanopsis, Q. gilva, Q. hondae, and Q. miyagii had |

| |very large vessels with a maximum vessel diameter over 200 μm. Within the species groups, |

| |individual species could not be identified just from wood structure, but Q. gilva could be |

| |distinguished when the distribution ranges of species were considered. The vertical splitting of|

| |semi-compound rays in Lithocarpus with the formation of a vertical wedge of fusiform cells |

| |differed from the ray development so far reported in Fagaceae or other taxa that have broad |

| |rays, and occurred only in the subgenus Pasania. |

|DOI: |10.1163/22941932-90000066 |

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