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Amalava Bhattacharyya and Santosh K. Shah

A large number of tree species, especially of conifers growing in the Himalaya and a few broad-leaved taxa in the peninsular region, have been dendrochronologically analyzed in India. This paper is a review providing information as regards the present status and future prospects of tree-ring research in India. Many trees are recorded to have datable tree rings but only some of them have been used for climate reconstruction and other aspects, e.g., glacial fluctuation or palaeo-seismic dating. In future not only ring width which is widely used so far, but also other tree-ring parameters need to be analyzed for a better understanding of the regional climate and its linkage with other climatic phenomena in a global perspective.

Anumeha Shukla and R.C. Mehrotra

. 2 ) Description – Wood diffuse porous. Growth rings present, marked by zones of dark coloured denser fibres. Vessels small to large, tangential diameter range 66–267 μm, mean 133 μm, solitary (about 70%) and in radial multiples of 2–5 (about 30%), occasionally in tangential pairs or clusters

Adya P. Singh, Yoon Soo Kim and Ramesh R. Chavan

Edited by Lloyd A. Donaldson

dumbbell shape of tunnelling bacteria across the middle lamella, with the constricted part of the bacterium often present within the confines of this cell wall, suggest that tunnelling bacteria possess an ability to undergo shape changes apparently in relation to the physical and chemical constraints

Robin Adey-Johnson, J. Paul Mclean, Jan Van den Bulcke, Joris Van Acker and Peter J. McDonald

preparation. A continuous radial position was assigned to each measurement based on its relative y -coordinate within the CT volume as the image y -axis is parallel to the radial direction of the specimen. Radial positions presented here are defined relative to the latewood boundary with the next annual

Bei Luo, Tomoya Imai, Junji Sugiyama, Sri Nugroho Marsoem, Tri Mulyaningsih and Takao Itoh

induced radial sieve elements (Sharma et al. 1980; Aloni & Barnett 1996). Recently, we found radial sieve tubes in the rays of the secondary xylem in Aquilaria malaccensis , A. sinensis , A. crasna and Gyrinops versteeghii (Thymelaeaceae, Malvales). The present study describes the occurrence and

Lloyd A. Donaldson, Adya Singh, Laura Raymond, Stefan Hill and Uwe Schmitt

. Because lignin (donor) and rhodamine (acceptor) form a FRET pair this facilitates the applicability of this technique to detecting probes within wood cell walls ( Donaldson et al. 2014 , 2018 ). In the present study, we extend this work to investigate differences in the cell wall porosity of sapwood

Thaís Jorge de Vasconcellos and Cátia Henriques Callado

elements of each type were present. The phenotypic plasticity index (PIV) were calculated for all wood anatomical features, as suggested by Valladares et al . (2006), based on maximum and minimum means. The maximum plasticity, according to Valladares et al. (2006), is PIV = 1.0. The vulnerability and

Jie Wang, Liping Ning, Qi Gao, Shiye Zhang and Quan Chen

Edited by Lloyd A. Donaldson

variable. These six characteristic compounds, alpha-Copaene, gamma-Euesmol, Agaruspirol, Guaiol, Gualazolene, and 7-epi-gamma-Euesmol must be present in the volatile components of the heartwood of P. zhennan buried wood. The buried wood samples must meet both anatomical and chemical criteria before they

Shahanara Begum, Osamu Furusawa, Masaki Shibagaki, Satoshi Nakaba, Yusuke Yamagishi, Joto Yoshimoto, Md Hasnat Rahman, Yuzou Sano and Ryo Funada

Edited by Lloyd A. Donaldson

secondary xylem cells are not fully understood ( Funada 2008 ). The role of actin filaments in controlling the orientation and localization of cortical microtubules remains to be clarified. The aim of the present study was to investigate the spatial and temporal relationship between actin filaments and

Achim Bräuning, Maaike De Ridder, Nikolay Zafirov, Ignacio García-González, Dimitar Petrov Dimitrov and Holger Gärtner

Wood anatomical features may be visible on the microscopic as well as on the macroscopic scale. While the former can often be quantified by detailed wood anatomical analyses, the latter are often treated as qualitative features or as binary variables (present/absent). Macroscopic tree-ring features can be quantified in terms of frequency, intensity, or classified according to their position within a tree ring, like intra-annual density variations (IADFs) in conifers or frost rings in earlywood or latewood. Although some of these tree-ring features, like e.g. missing rings or IADFs are often seen as anomalies, hampering dendrochronologists to perform proper crossdating of tree-ring series, many of these properties are formed under extreme environmental stress or heavy impact, and could mark these extreme events by the manifestation in the wood anatomical structures throughout the lifespan of trees. The described tree-ring features form discrete time-series of extreme events. For example, flood rings may be marked by lunar-shaped earlywood vessels or enlarged latewood vessels in ring-porous oaks. White earlywood rings and light rings indicate reduced cell wall thickness and lignification occurring in very cold years. Frost rings result from cambial cell death during abrupt cooling events in the growing season. Missing rings and IADFs are mainly caused by drought events. Characteristic variations in earlywood vessel size, shape, or number in ring-porous oak species are markers for flood events, defoliation, heat stress, or drought. Traumatic resin ducts may be triggered by a range of biotic or environmental stressors, including wounding, fires or mechanical factors. Reaction wood is indicative of mechanical stress, often related to geomorphic events. In many cases anatomical responses are unspecific and may be caused by different stressors or extreme events. Additionally, the sensitivity of trees to form such features may vary between species, or between life stages within one species. We critically evaluate the indicative value of different wood anatomical tree-ring features for environmental reconstructions.