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Dr. Alexander Eig is a figure of major importance in the history of botany in Israel. This paper attempts to evaluate, for the first time, personal contacts that influenced his academic development. Archival research reveals that his meeting with one of the greatest plant researchers of the 20th century, N.I. Vavilov, in 1926 had a great impact upon him. It was Vavilov who stimulated the young Alexander Eig to undertake his first taxonomic work and write his first monograph. This article reproduces and discusses a newly discovered letter, written by Vavilov to Yitzhak Volcani, the head of the Institute of Agriculture and Natural History in Israel, under whose leadership Eig began his academic work. This document points to the existence of a mutual understanding and cooperation between Vavilov and Volcani. Furthermore, Vavilov’s letter explains why Eig’s academic work, and that of generations of Israeli botanists who followed in his footsteps, chartered the path it took.

In: Israel Journal of Plant Sciences
A Comprehensive History of Tea from Prehistoric Times to the Present Day
The Tale of Tea is the saga of globalisation. Tea gave birth to paper money, the Opium Wars and Hong Kong, triggered the Anglo-Dutch wars and the American war of independence, shaped the economies and military history of Táng and Sòng China and moulded Chinese art and culture. Whilst black tea dominates the global market today, such tea is a recent invention. No tea plantations existed in the world’s largest black tea producing countries, India, Kenya and Sri Lanka, when the Dutch and the English went to war about tea in the 17th century. This book replaces popular myths about tea with recondite knowledge on the hidden origins and detailed history of today’s globalised beverage in its many modern guises.

ABSTRACT

We revisited questions about changes in the incidences of functional wood anatomical traits through geologic time and compared the incidences of these traits in the fossil record with modern wood anatomical diversity patterns in order to test classical (“Baileyan”) and more recent ecophyletic hypotheses of xylem evolution. We contrast patterns through time for tropical and higher (paleo)latitudes. Data are from the InsideWood database. There are striking differences between woods from high and mid latitudes versus tropical (paleo)-latitudes. At temperate and subtropical latitudes (Laurasia and high latitude Gondwana), the epoch by epoch time series supports the Baileyan transformation series of vessel-bearing woody angiosperms (basal woody angiosperms and eudicots): “primitive” features such as scalariform perforations, exclusively solitary vessels, apotracheal diffuse parenchyma and heterocellular rays abound in the Cretaceous and become much less frequent in the Cenozoic, especially post-Eocene. In contrast, in the paleotropics hardly any changes occur in the incidences – each epoch has an equally “modern” spectrum of wood anatomical attributes. Although climatic gradients from the poles to the equator were less steep in the Cretaceous than in the late Cenozoic, the wood anatomical differences between mid-high latitude woods and tropical woods were much more pronounced in the Cretaceous than in later epochs. This seeming paradox is discussed but we cannot resolve it.

We suggest that tropical conditions have accelerated xylem evolution towards greater hydraulic efficiency (simple perforations), biological defense and hydraulic repair (elaborate paratracheal parenchyma patterns) as evidenced by late Cretaceous tropical latitude woods having near modern incidences of almost all traits. At higher paleolatitudes of both the Northern and Southern Hemisphere “ancestral” features such as scalariform perforations were retained in cooler and frost-prone regions where they were not selected against in mesic habitats because of lower demands on conductive efficiency, and could even be advantageous in trapping freeze-thaw embolisms. The fossil wood record remains too incomplete for testing hypotheses on the wood anatomy of the earliest angiosperms. The low incidence of so-called “xerophobic” woods sensu Feild with scalariform perforations with numerous (over 40) closely spaced bars in the Cretaceous tropical fossil record is puzzling. At higher paleolatitudes such woods are common in the Cretaceous.

Ring porosity, an indicator of seasonal climates and deciduousness, occurs at low levels in the Cretaceous and Paleogene at higher paleolatitudes only, and reaches modern levels in the Miocene. In Neogene and Recent temperate Northern Hemisphere, wide vessels are virtually restricted to ring-porous woods. In the tropics, there is a low incidence of ring porosity throughout all epochs.

The fossil record indicates that ecophysiological adaptation to tropical or temperate conditions was already evident in the Cretaceous with considerable latitudinal differences.

In: IAWA Journal

Abstract

Mango burl is an important disease affecting many mango plantations in India and causes great loss in yield and decrease of vigour. We carried out a diagnostic survey for burl disease (sometimes also referred to as crown gall) in different varieties of mango (Mangifera indica L., Anacardiaceae) throughout India during 2015 and 2016. More than 500 mango genotypes were screened for disease susceptibility and more than twenty-three mango genotypes in different parts of India were found susceptible to this disease. Burls initiate as small tumorous growths and become more pronounced as warty outgrowths with the increasing age of the individual tree. Samples of burl were collected from all popular varieties from different parts of the country and subjected to histological investigations.

The present study confirms that mango burl disease is caused by Agrobacterium tumefaciens using evidence from the “carrot assay” and molecular identification of the presumed causal organism. The latter was isolated and inoculated on carrot disks to induce typical symptoms.

The xylem of the burl tissue was deformed and showed no specific orientation of the wood cells. Dimensional details and morphology of xylem cells vary at different positions within the burl. In a 10 cm diameter burl, the marginal portion showed xylem cells in circular arrangement. Vessel elements and fibres were very short while rays were relatively low and biseriate rays were observed rarely. Orientation of the xylem tissue was lost and all three plains (i.e. transverse, tangential and radial view) were observed in the same section. Cells from the middle portion of the burl were isodiametric, oval to circular, thick-walled and lignified, in morphology not dissimilar from callus tissue. Tyloses were common in all the cell types viz. fibres, ray cells, tracheids, axial parenchyma cells, and vessel elements.

In: IAWA Journal

Abstract

The characteristics of cross-field pitting among compression wood, lateral wood, and opposite wood, in the stem woods of Ginkgo biloba and Pinus densiflora were investigated with optical and scanning electron microscopy. In Ginkgo biloba, compression wood exhibited piceoid pits, while lateral and opposite wood exhibited cupressoid pits. The compression wood of Pinus densiflora exhibited cupressoid pits and piceoid pits, while lateral wood and opposite wood exhibited pinoid and window-like pits in the cross-field. In both species, compression wood yielded the smallest pit number among each part, while opposite wood yielded the greatest pit number per cross-field. Cross-field pitting diameters of compression wood and opposite wood were significantly smaller than lateral wood in Ginkgo biloba, while the cross-field pitting of compression wood was the smallest in Pinus densiflora. Radial tracheid diameter of compression wood was slightly smaller than lateral and opposite wood in Ginkgo biloba and significantly smaller than lateral and opposite wood in Pinus densiflora. In conclusion, the cross-field pitting type, pit number, and cross-field pitting diameter could be used to identify reaction wood in the stem wood of Ginkgo biloba and Pinus densiflora.

In: IAWA Journal

Abstract

Paper quality depends on fiber diameter and wall thickness, and their derivatives. Fiber deformation occurs due to pressure from the vessel during development. The diameter and wall thickness of the fibers were measured following the direction of pressure exerted by the vessel on the face of the fiber cells. Fiber cell diameter measured perpendicular to and parallel with vessel enlargement was referred to as radial and tangential diameter, respectively, and likewise for fiber wall thickness. Differences in radial and tangential diameter and wall thickness of fiber cells in relation to their distance from vessels were analyzed. The radial diameter of fibers adjacent to large vessels decreased from the first to the fifth fiber, and from the first to the second fiber adjacent to small vessels. Conversely, tangential fiber diameter increased from the first to the fifth fiber for fibers adjacent to large vessels, and from the first to the second fiber adjacent to small vessels. The fibers adjacent to the vessel seem to have thicker walls in both the tangential than radial directions up to 2 and 5 fibers for small and large vessels, respectively. The first two fibers adjacent to small diameter vessels may produce higher strength paper than those up to five fibers from large diameter vessels, because the Runkel ratio, Coefficient of rigidity and Muhlsteph ratio values of fibers adjacent to small vessels are lower than fibers adjacent to large vessels. The opposite occurs for flexibility coefficient values.

In: IAWA Journal

Abstract

We aimed to explore the effects of different concentrations, in particular, high concentrations, of exogenously applied ethephon and methyl jasmonate on gum duct formation in three broad-leaved tree species, Cerasus × yedoensis, Prunus mume and Liquidambar styraciflua. Intact shoots were treated with ethephon and methyl jasmonate in lanolin paste at concentrations of 0.1%, 1%, 2%, 5%, and 10% (w/w). The ethephon treatments induced gum duct formation in the xylem adjacent to the cambium in all three species, whereas the methyl jasmonate treatments did not. The highest induction of gum duct formation was observed after 1–2% ethephon treatments in C. × yedoensis and P. mume, and after 5–10% ethephon treatments in L. styraciflua. Meanwhile, the treatments with higher ethephon concentrations resulted in a lower induction of gum duct formation in C. × yedoensis and P. mume. In addition, we examined gum duct formation at sites distant from the treatment sites in C. × yedoensis and P. mume shoots treated with 10% ethephon. Gum duct formation was found to be the highest at sites 2 cm away from the treatment site (in the acropetal direction). We show that at least in C. × yedoensis and P. mume, trees have an optimal concentration of ethephon to induce gum duct formation, and that concentrations higher than the optimum suppress the induction.

In: IAWA Journal

Abstract

Wood identification has never been more important to serve the purpose of global forest protection, by controlling international illegal timber trade and enabling the enforcement of timber trade regulations. Macroscopic wood identification is the fastest method for the first identification of an unknown timber and, with proper training, it can be performed by operators in the timber industry, restorers and curators of cultural heritage, wood traders, designers, students and customs officers. Here we describe a wood atlas and accompanying software, SIR-Legno, developed for the identification of 48 Italian timber species based on a recently proposed list of macroscopic features for wood identification. For each species the atlas provides a complete macroscopic description plus information on natural durability, end-use class, physico-mechanical properties, conservation status, maximum diameter of the bole and most frequent uses. For each genus covered by the atlas, information about species number, CITES-listed species, main commercial timbers, similarly-named timbers from other genera, geographical distribution and notes on species or species group recognition at macroscopic and microscopic level are provided. SIR-Legno is an educational product, a handy identification key and a tool to search woods by their natural durability, end-use class and physico-mechanical properties. Both the atlas and the software can be freely downloaded from the web. Thanks to the adoption of a codified list of characters and a transferable design, SIR-Legno can be easily replicated or expanded to other databases in order to include new species. SIR-Legno is freeware and works on any version of Windows.

In: IAWA Journal

ABSTRACT

Most evolutionary innovations in plant vascular tissues, including secondary growth, occurred during the Devonian period (~420 to 360 million years ago). Such innovations had a major impact on land colonisation by plants and on their biodiversity. Here, we show the hydraulic conductance of the secondary xylem of three shrubby or arborescent plant fossils (a probably new genus of Cladoxylopsida, the archaeopteridalean genus Callixylon and the stenokolean genus Brabantophyton). Evidences come from the Ronquières fossil site (Belgium). This site is considered mid-late Givetian/earliest Frasnian in age. Results reveal that hydraulic conductivity of these early woody plants is more or less similar to that of modern gymnosperms, meaning that water transport was already as efficient in Devonian plants as it is in living plants. Our results further suggest that tracheids with features helping for optimised water transport were quickly selected in the evolutionary history of vascular plants.

In: IAWA Journal

ABSTRACT

This contribution presents descriptions of 14 fossil woods from the Piedra Chamana Fossil Forest in Peru, an assemblage of fossil woods and leaves dated at 39 Ma (late Middle Eocene). It is part two of the descriptions of the non-monocot angiosperm fossils from the site (see Woodcock et al. 2017). The woods are assigned to the subfamilies Bombacoideae, Bombacoideae/Malvoideae, Byttneroideae, Grewioideae, and Sterculioideae of Malvaceae and the families Melastomataceae, Muntingiaceae, Rubiaceae, Rutaceae, and Sapindaceae. Malvalean taxa make up around one-third of the wood types. Many of the woods are identifiable to modern-day genera or groups, including genera with species counted among the hyperdominant trees of the New World forests. Represented vegetation types include mixed freshwater swamp with Avicennia, seasonally flooded forest, and lowland tropical forest with a dry aspect. The assemblage shows floristic similarities to extant South American lowland tropical forest, particularly the seasonally flooded forests growing along white water rivers (várzea); however, the dry forest association has a less clear analog in the present-day tropics.

In: IAWA Journal