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Abstract

During the cropping season 2016-2017, an experiment was conducted in a split plot design to study the response of 25 wheat genotypes to drought stress under irrigated and minimal irrigation conditions. Different drought tolerance indices for 25 bread wheat (Triticum aestivum L.) genotypes were evaluated. The calculation drought tolerance indices was based on the grain yield of wheat under irrigated and water stress conditions. The result indicated a significant effect of drought stress on the yield of different wheat genotypes based on mean values of different drought tolerance indices. Among the studied different indices, mean productivity (MP), stress tolerance index (STI), and geometric mean productivity (GMP) were more efficient to discriminate between drought sensitive and drought tolerant genotypes based on the calculation of correlation coefficient and multivariate analysis. Twenty-five genotypes were classified into tolerant and susceptible groups through drought tolerance indices using cluster analysis. Among the genotypes, C-306, WH 1236, WH 1235, and GW 477 having higher yields under drought conditions which showing their stability under stress conditions. The most yield stable genotypes under adverse environment were identified by multivariate analysis of drought tolerance indices individually or in combination. From the result, we concluded that GMP, MP and STI are more efficient drought tolerance indices among other indices to identify stable genotypes under stress conditions.

In: Israel Journal of Plant Sciences

Summary

Axial parenchyma proliferation (non-lignified parenchyma) in wood has been characterized for only a few species. In the present study, we characterized the proliferation, ontogeny, and seasonal variation of wood axial parenchyma in Cochlospermum vitifolium (Bixaceae). This study included material from natural populations from different sites in Mexico. We analyzed the wood anatomy and development in stems of different ages, and monthly sampling of the main stem during the growing season. The results show that the wood anatomy of C. vitifolium is characterized by features associated with efficient water transport, such as wide vessels and low vessel frequency. The wood has a high storage and radial transport capacity. Axial parenchyma is abundant and constitutes the main cell type of the wood. Rays are wide and tall with a high starch content. Ontogenetic development of the wood showed that non-lignified axial parenchyma differentiates after secondary growth has been established. Parenchyma proliferation does not occur in an axially orderly fashion and the results suggest that there is a relationship between maximum proliferation and precipitation. We found high variation in wood parenchymatization between trees. The maximum parenchymatization and succulence was found in trees with larger stem diameter. The ecological and ontogenetic implications of wood parenchymatization are discussed.

In: IAWA Journal

Summary

Wavy grain (fiddle back) in trees has attracted the interest of both science and industry due to its aesthetic and economic importance. As the underlying causes of this particular structural feature in trees remain uncertain, this study investigates the possibility of non-invasively detecting wavy grain patterns within tree bark tissue of sycamore maple (Acer pseudoplatanus). Wavy grain, characterized by alternating light and dark stripes on the wood surface, is highly valued in the production of musical instruments. This research explores the potential of employing transmission light microscopy and microcomputer tomography (μCT) to examine the internal structure of phloem tissue to inspect whether the wavy grain structure found in the xylem continues in the bark. The investigation of phloem tissue proved challenging due to its irregular cellular arrangement. Nonetheless, slight phloem fibre deviations were observed in individual trees. However, no definite connection was found between the periodic oscillations of the xylem fibre tissue and the structure of the phloem in a given area. Variability in wavy grain expression among the xylem of the trees posed an additional challenge, with amplitudes and wavelengths differing across specimens. The application of μCT offered advantages over traditional sample preparation, enabling the study of the anatomical structure across larger areas and multiple depths without altering the specimen. This study sheds light on the potential of employing advanced imaging techniques to detect wavy grain patterns, providing insights that could benefit industries reliant on high-quality wood, such as musical instrument crafting and forestry.

In: IAWA Journal

Summary

The physiological and ecological adaptions of higher plants are driven by anatomical changes that contribute to the evolution of the climbing habit. This not only makes them able to survive in a dry environment but also supports them to undergo secondary growth and complete their reproduction. Some plants even form aerial roots as a survival strategy. In the present study, the anatomy of both aerial and underground roots and stems in Zanonia indica L. (Cucurbitaceae) is investigated. In young stems, vascular bundles (VB) had sieve elements on the inner margin of the protoxylem elements (i.e., bicollateral VB). In stems as well as aerial and underground roots, the axial elements of the secondary xylem were arranged in radial plates separated by wide medullary rays. Aerial and underground roots shared similar features in having exarch protoxylem and distinct narrow piths. Structurally, the secondary xylem was composed of vessels, tracheids, fibres, axial and ray parenchyma cells while extra-fascicular sieve elements were observed only in stems and aerial roots. The formation of aerial roots is a survival mechanism whose significance is discussed with reference to the available literature.

In: IAWA Journal

Abstract

Identification of different pomegranate (Punica granatum L.) genotypes using morphological descriptors and further substantiated through molecular means is essential for a breeding program. Characterization using molecular markers has an advantage over its morphological counterpart due to its low expense, quick and reliable results, and the requirement of less sophisticated equipment. In this study, eight different pomegranate cultivars were characterized based on their morphological and molecular characters in sub-tropical regions between 2018 and 2019. Morphological experiments were conducted in a randomized block design replicated thrice for each cultivar, whereas RAPD markers were employed for molecular studies. Principal component analysis revealed significant morphological variation (79.61%) among the cultivars. A high level of polymorphism, similar to PCA, was observed with RAPD analysis (80.49%). Some discrepancies between morphological and molecular results were noted in UPGMA cluster analysis. However, eight primers (total = 41) distinctively separated the Bhagwa variety from others, with the maximum similarity coefficient value (ca. 0.54) and superior fruit quality distinguished in PCA analysis with the maximum mean Euclidean distance (ca. 16). Hence, RAPD markers could be used along with morphological markers for a quick screening of germplasms in further crop improvement programs.

In: Israel Journal of Plant Sciences

Summary

Computer vision-based wood identification has been successfully applied to recognize tree species using digital images of wood sections or surfaces. However, this image-to-species approach can only recognize a limited number of species due to two main reasons: 1) the lack of a good reference database requiring high-quality standardized images from multiple individuals of hundreds or even thousands of traded timber species, and 2) species not included in the reference database cannot be identified without expert knowledge. Another bottleneck is that the feature extraction process used by these species recognition approaches is a black box, thereby creating a discrepancy between machine learning features and wood anatomical features. This discrepancy prevents wood anatomists from understanding how these machine-learning algorithms work. Here, we survey currently existing methods used in feature extraction, classification, and deep learning methods applied in wood identification along with their pitfalls and opportunities. As an example of how the field could move forward, we launch the idea of building an image-to-features-to-species identification approach based on microscopic wood images as well as text files comprising wood anatomical descriptions. If we can manage machine learning-based algorithms to recognize the main wood anatomical traits that experts use to identify species in a (semi-)automated way, this would boost wood identification in two ways: (1) extensive reference databases for each species would become less crucial as the databases are ordered at the trait level, (2) timber identification would become more feasible for species that have not yet been included in the reference database as long as wood anatomical descriptions are available.

Open Access
In: IAWA Journal

Summary

Grapevine (Vitis vinifera) is the most widely cultivated and economically relevant crop in the world, but its productivity is menaced by aridification in some wine-growing regions such as the Mediterranean Basin. The impacts of climate on vines depend on regional conditions, cultivar, and vine age, among other factors. Hence, a better understanding of vine radial-growth responses to climate in different regions is sorely needed. First, we related climate data and drought severity with a long-term series of vine leaf unfolding from NE Spain to test if climate warming is advancing the onset of the growing season. Second, we used growth rings to estimate age and quantify climate-growth relationships of vines using dendrochronology. Three sites from different designations of origin and vine varieties were studied: Logroño in northern Spain (La Rioja, Tempranillo), San Martín del Río in northeast Spain (Calatayud, Garnacha) and Anzi in southern Italy (Aglianico, Aleatico). Vine leaf unfolding occurred earlier as winter-spring conditions were warmer and drier. Vine ages ranged between 16 (Logroño, Anzi) and 56 years (S. Martín del Río), and growth rates declined in the two youngest grapevines. Ring widths varied between 1.19 (S. Martín del Río) and 1.80 mm (Logroño), with Anzi showing intermediate values (1.37 mm). February precipitation enhanced vine growth in San Martín del Río ( r = 0.64 ) and Anzi ( r = 0.49 ), whereas the correlation with soil moisture peaked in March in San Martín del Río ( r = 0.83 ). Vine growth rates positively responded to September minimum temperatures in San Martín del Río ( r = 0.51 ) and Logroño ( r = 0.50 ). Garnacha cultivar in San Martín del Río showed the highest responsiveness to water availability. Therefore, similar old grapevines from continental, seasonally dry areas could be the most negatively affected by future warmer and drier climate conditions.

In: IAWA Journal

Summary

A comprehensive analysis was conducted using optical microscopy based on wood anatomy to enhance the preservation of wooden components in Tingbao Yang’s former residence. This study identified wood samples, and statistical examination of wood species, variations in their configuration, physical and mechanical properties, and natural durability were examined. The principles for wood species selection were assessed. Findings indicate that Cunninghamia lanceolata, Pseudotsuga spp., Populus spp. and Ulmus spp. are the primary choices for these wooden components. However, certain portions incorporate Larix sect. Multiseriales, Picea brachytyla, Pinus bungeana, Pinus massoniana, Castanea sp. and Quercus subg. Lepidabalanus, sect. Prinus. Pseudotsuga spp., C. lanceolata, Ulmus spp. and Populus spp. are primarily utilized for wooden columns and melon columns. However, C. lanceolata, Ulmus spp. and Populus spp. possess inadequate parallel grain compressive strength for load-bearing compression wooden components. C. lanceolata and Ulmus spp. are widely utilized in beams, lintels, purlins, and rafters owing to their exceptional bending strength. It was noted that Castanea sp. and Quercus subg. Lepidabalanus, sect. Prinus wood varieties demonstrate superior resistance to rotting and insects compared with other types of wood. The selection of wood species for the ancient buildings of Tingbao Yang’s former residence relies on crucial principles, such as the suitability of wood properties and local selection. This selection process involves analyzing the wood properties, assessing the natural durability of wooden components, and considering the distribution of forest resources in Henan Province.

Open Access
In: IAWA Journal
Authors: and

Summary

A splinter of charred wood was recovered from late Early Eocene volcanoclastic deposits underlying the lacustrine succession of the Messel-pit near Darmstadt (Hesse, Germany). Well-preserved anatomical details due to charring allow for an attribution of the splinter to the Oleaceae family. Within Oleaceae, the wood shows good agreement with the anatomical structure of recent members of the genera Olea, Chionanthus and Noronhia. However, due to the high variability of structural features within this group of genera, a reliable taxonomic placement is restricted to the monophyletic drupaceous subtribe Oleinae. The Splinter was cut loose from a tree of the local vegetation and charred by effects of the respective phreatomagmatic eruption, even under a low-fire regime. The specimen represents a rare example of a Pre-Quarternary wood that can be related directly to a radiometric age of 48.27–48.11 Ma (±0.22 Ma).

In: IAWA Journal

Summary

Forest fires play a significant role in the growth and development of trees because they can damage the phloem and cambium. Fire injury induces the formation of fire scars that can cause xylem dysfunction. The study area is located in Taşköprü, Kastamonu (Western Black Sea of Turkiye), where two forest fires occurred in 1957 and 2020. In this study, the effect of the 1957 fire on the tree-ring widths and tracheid dimensions of Pinus nigra trees was investigated. We measured tree-ring widths and tracheid dimensions of fire-scarred (FS) and unscarred (UF) trees during four different periods: the pre-fire period (1947–1956), fire event year (1957), and post–fire periods (1958–1967 and 2011–2020). In this study, UF trees showed almost 2.5–3 times wider tree–ring widths (TRWs) than FS trees. FS and UF trees also showed great variation in tracheid dimensions in the four different periods; the average tracheid diameter (TD), lumen area (TLA), and wall thickness (TWT) values increased significantly in UF trees compared to FS trees during the fire event and post-fire periods. The average TD, TLA, and average tracheid lumen diameter (TLD) decreased during the fire and post-fire years in the FS trees. In this study, we suggest that fire injury significantly affects the tracheid dimensional traits of FS Pinus nigra trees. Our results also suggest that although Pinus nigra trees experienced serious fire damage, they continued to grow but with a decrease in tracheid size.

In: IAWA Journal