Preservation Of Plant Material Research Articles

The study of perspective medicinal plants using the example of Helianthus tuberosus L.

This paper presents the results of microscopic analysis of a perspective medicinal plant Helianthus tuberosus used for the treatment of diabetes mellitus. The study was conducted to identify specific morphological and structural characteristics of this plant, which may have a positive impact on the efficacy and safety of its use for medical purposes. Different types of plant material were used in the research: fresh plants, dried plant material and preserved plant material. For preservation of the latter, a special mixture consisting of ethyl alcohol, glycerol and distilled water in equal volumes was used. Anatomical study of the structure and structure of plants was carried out using several methods: to study the structure of the epidermis, surface samples were prepared, which allowed us to get a detailed idea of the cellular composition and location of the epidermis on the surface of leaves, stems and roots of plants; for a deeper study of the internal structure of plants, transverse sections were made, which were further investigated. The results of the study suggest the high potential of this plant as a basis for the development of safe and effective phytopreparations.

The Devonian landscape factory: plant–sediment interactions in the Old Red Sandstone of Svalbard and the rise of vegetation as a biogeomorphic agent

The Devonian Period was a crucial interval in the evolution of plants. During its 60 myr duration, it witnessed the successive evolution of roots, wood, trees and forests. In addition, many of the biogeomorphic phenomena that operate in modern terrestrial environments came online for the first time. The ‘Old Red Sandstone’ of Svalbard consists of a near-continuous Silurian to Late Devonian record of sedimentary environments colonized by land plants and provides a perfect natural laboratory to aid our understanding of the facies signatures and evolution of these phenomena. We describe and illustrate a catalogue of ‘Old Red Sandstone’ features that provide evidence for the stepwise appearance of novel plant–sediment interactions, including preserved plant material and rooting structures, early large woody debris accumulations, cannel coal deposits and the oldest known vegetation-induced sedimentary structures, in addition to vegetation-influenced motifs of elevated mudrock content and complex alluvial sand bodies. These characteristics are combined to reconstruct changes to non-marine environments in this Devonian ‘landscape factory’. In addition to tectonic and climate influences, plant evolution first served as a control on the construction of the sedimentary record during this period and has persisted as a fundamental influence on Earth surface processes and landforms ever since.

The influence of volcanic activity and trophic state on plant taphonomic processes in Triassic lacustrine-deltaic systems of western Gondwana

The impact of volcanic activity and trophic state on the preservation of plant remains from two Triassic palaeolake deposits in western Gondwana is investigated. Six taphonomic modes are identified for the Potrerillos–Cacheuta sequence and the Los Rastros Formation, along with proposed taphonomic pathways for each mode. The taphonomic pathways were compared with those proposed for the Agua de la Zorra Formation, a coeval lacustrine-deltaic succession. In all three cases, plant preservation in off-shore lacustrine facies was enhanced by anoxic bottom conditions. In the more proximal near-shore facies, a high sedimentation rate would have been factor that enhanced the preservation. Variation in relative abundance and taxonomic diversity between the three successions are attributed to ecological differences rather than taphonomic differences among the lake systems. No evidence was recorded that the preserved plant material was produced by volcanic trauma. The preservation of the cuticle recorded in the Cacheuta Formation was likely enhanced by the apparently low thermal maturation of the rock and the presence of tuffaceous horizons. In the three successions, the abundance and distribution of remains throughout the sections suggest that the trophic state of the lake did not influence the preservation of the plant.

PLANT TAPHONOMY IN A LAKE AFFECTED BY VOLCANISM (AGUA DE LA ZORRA FORMATION, UPPER TRIASSIC) MENDOZA, ARGENTINA

ABSTRACTVolcanic eruptions have an impact on the paleoecology of plant communities and their preservation in the fossil record. The aim of this contribution is to evaluate the influence of volcanism on plant preservation in lacustrine settings via systematic sampling and chemical analyses of fossil plants in the Upper Triassic Agua de la Zorra Formation, of the Argentinian Cuyana Basin. Plant remains are not uniformly preserved throughout the Agua de la Zorra Formation and their stratigraphic distribution reflects the original spatial pattern of the plant communities. SEM-EDX analyses was used to demonstrate how volcanism affected diagenesis of the plant remains. Eight taphonomic modes were determined from biostratinomic analysis, and three preservational modes from the chemical features observed in the SEM-EDX spectra. The three preservation modes recognized by SEM-EDX analysis are more likely linked to diagenesis and are not equivalent to the taphonomic modes described based on the biostratinomic features. The Agua de la Zorra paleolake preferentially preserved plant material because of anoxic conditions in deeper parts of the lake, and a high sedimentation rate in proximal near-shore facies. The plant remains are most abundant in sandy facies deposited by high-energy flows but there is no evidence that these flows were pyroclastic nor that the plant remains were generated by volcanic trauma.

Machine Learning Using Digitized Herbarium Specimens to Advance Phenological Research.

Machine learning (ML) has great potential to drive scientific discovery by harvesting data from images of herbarium specimens—preserved plant material curated in natural history collections—but ML techniques have only recently been applied to this rich resource. ML has particularly strong prospects for the study of plant phenological events such as growth and reproduction. As a major indicator of climate change, driver of ecological processes, and critical determinant of plant fitness, plant phenology is an important frontier for the application of ML techniques for science and society. In the present article, we describe a generalized, modular ML workflow for extracting phenological data from images of herbarium specimens, and we discuss the advantages, limitations, and potential future improvements of this workflow. Strategic research and investment in specimen-based ML methods, along with the aggregation of herbarium specimen data, may give rise to a better understanding of life on Earth.

Morfología de semillas de siete especies del género Opuntia (Cactaceae) del sureste de Coahuila (México)

Introducción y Objetivos: Opuntia se distribuye naturalmente desde Canadá hasta Argentina, actualmente forma parte del paisaje en algunas regiones del mundo, comprende entre 191 y 215 especies; la conservación ex situ de este recurso fitogenético ha adquirido relevancia, pero la identificación de especies por semilla es una limitante cuando no se tienen caracteres morfológicos confiables. El objetivo del estudio fue caracterizar la morfología de semillas de siete especies de Opuntia e identificar caracteres morfológicos propios, para tener un criterio en la identificación de especies cuando el material vegetal conservado es semilla. M&M: Mediante la técnica de desgaste y análisis de imágenes se evaluó: grosor de testa (GT), grosor de la cubierta funicular ventral (GCFV), longitud del embrión (LE), área del embrión (AE), longitud del eje mayor (LEMA) y del eje menor (LEME). Por medio de ANDEVA exploratorios y componentes principales (CP) se detectaron los caracteres más sobresalientes. Para la clasificación y predicción de especies se realizó un análisis supervisado con los métodos K-NN y LDA.
 Resultados: Las diferencias en todas las variables entre especies fueron significativas. Opuntia ficus-indica presentó semillas de mayor tamaño. Las variables que más ayudan a discriminar son GCFV y GT. El análisis de componentes principales explicó el 92% de la variación total. El método de predicción K-NN, fue capaz de predecir correctamente el 83% de los casos en la clasificación de las especies.
 Conclusiones: Los caracteres de semillas evaluados, principalmente el GCFV y GT, pueden coadyuvar en la descripción morfológica de las especies de nopal o o en identificación de especies de Opuntia cuando sólo se tiene semilla.

Geophysical expression of the Meyers Crater, a new meteorite impact crater discovered in the Coolgardie Goldfield of Western Australia

SummaryDetailed airborne electromagnetic (VTEM), gravity and passive seismic HVSR surveying, followed up by RC and diamond drilling, has identified an isolated circular and geologically young meteorite impact crater filled with sediments and located next to the town of Coolgardie in Western Australia. It was discovered in 2017 (Meyers, 2017), is 800 m in diameter and estimated to be >140 m deep based on passive seismic results, because only angled drilling was carried out for gold exploration along the western side of the crater. The crater has been filled with impact debris and sedimentary deposits to form a flat modern topographic feature. The pre-impact bedrock is Archean greenstone, which hosts numerous gold occurrences and mines surrounding the crater. The crater is filled with a polymict impact breccia of mixed greenstone rocks from below and surrounds near its base. A thin (<2 m) tuffaceous looking ejecta layer occurs at the boundary between the impact breccia and underlying in situ brecciated greenstone bedrock (high Mg basalt and ultramafic lava). This transition zone is also imaged as two “bedrock” layers in passive seismic HVSR cross-sections. The impact breccia is overlain by a very thick deposit of anoxic peat and carbonised wood fragments containing framboidal pyrite, as well as slump blocks of greenstone rocks, starting from over 120 m deep to a depth of 14 m from surface, where this organic layer is capped by a fine clay deposit, which was likely transported into the crater after its raised rim was breached by erosion. The crater and its fill deposits cannot explain the entire circular gravity anomaly low of -5mGal, and the brecciated in situ greenstone bedrock around and below the crater is modelled to contribute to the gravity anomaly low. It is estimated that the meteorite projectile was about 40 m in diameter, came from an easterly trajectory, and impacted Coolgardie between the Miocene to Pleistocene, with age dating and Ir analysis of the impact layer and overlying plant material soon to be carried out. A high-resolution ground magnetic survey using 10 m line spacing was carried out to try and detect large iron meteorite fragments, but only a weak and diffuse anomaly pattern occurs at the crater centre, indicating that the meteorite was highly fragmented on impact and/or later demagnetised by weathering. A vertical diamond drillhole down the centre of the crater is required to properly study this relatively young impact structure and analyse the preserved plant material filling the crater over a vertical column of 100 m or more, continuously recording local environmental changes over a considerable time period.

A Workflow for Data Extraction from Digitized Herbarium Specimens

Based on own work on species and trait recognition and complementary studies from other working groups, we present a workflow for data extraction from digitized herbarium specimens using convolutional neural networks. Digitized herbarium sheets contain: preserved plant material as well as additional objects: the label containing information on the collection event, annotations such as revision labels, or notes on material extraction, identifiers such as barcodes or numbers, envelopes for loose plant material and often scale bars and color charts used in the digitization process. preserved plant material as well as additional objects: the label containing information on the collection event, annotations such as revision labels, or notes on material extraction, identifiers such as barcodes or numbers, envelopes for loose plant material and often scale bars and color charts used in the digitization process. In order to treat these objects appropriately, segmentation techniques (Triki et al. 2018) will be applied to localize and identify the different kinds of objects for specific treatments. Detecting presence of plant organs such as leaves, flowers or fruits is already a first step in data extraction potentially useful for phenological studies. Plant organs will be subject to routines for quantitative (Gaikwad et al. 2018) and qualitative (Younis et al. 2018) trait recognition routines. Text-based objects can be treated as described by Kirchhoff et al. 2018, using OCR techniques and considering the many collection-specific terms and abbreviations as described in Schröder 2019. Additionally, species recognition (Younis et al. 2018) will be applied in order to help further identification of incompletely identified collection items or to detect possible misidentifications. All steps described above need sufficient training data including labelling that may be obtained from collection metadata and trait databases. In order to deal with new incoming digitized collections, unseen data or categories, we propose implementation of a new Deep Learning approach, so-called Lifelong Learning: Past knowledge of the network is dynamically saved in latent space using autoencoder and generatively replayed while the network is trained on new tasks which enables it to solve complex image processing tasks without forgetting former knowledge while incrementally learning new classes and knowledge.

Using herbaria to study global environmental change.

SummaryDuring the last centuries, humans have transformed global ecosystems. With their temporal dimension, herbaria provide the otherwise scarce long‐term data crucial for tracking ecological and evolutionary changes over this period of intense global change. The sheer size of herbaria, together with their increasing digitization and the possibility of sequencing DNA from the preserved plant material, makes them invaluable resources for understanding ecological and evolutionary species’ responses to global environmental change. Following the chronology of global change, we highlight how herbaria can inform about long‐term effects on plants of at least four of the main drivers of global change: pollution, habitat change, climate change and invasive species. We summarize how herbarium specimens so far have been used in global change research, discuss future opportunities and challenges posed by the nature of these data, and advocate for an intensified use of these ‘windows into the past’ for global change research and beyond.

Synvina to extend PEF pilot phase

This work discusses the effects of pulsed electric field (PEF), ohmic heating (OH), and osmotic (O) treatments on the structure of apple tissue and its freezing/thawing behaviour. Apple discs were treated at electric field strength E = 800 V/cm (PEF, isothermal regime) and E = 40 V/cm (OH, non-isothermal regime) to a high level of tissue disintegration (conductivity disintegration index Z was ≈ 0.98) and then were subjected to osmotic (O) treatment in the aqueous solution of glycerol (20 wt.%). The distribution of osmotic solution was practically homogeneous inside the disc of PEF-treated tissue and highly inhomogeneous in untreated and OH-treated samples. The freezing–thawing (FT) experiments (+ 20 °C → − 40 °C → + 20 °C) were done in order to reveal the effects of combined modes of treatment on the structure of apple tissue. The most pronounced reducing of both freezing and thawing times and strengthening of the apple texture were observed for PEF treatment.Freezing-assisted preservation of plant materials in the most natural-looking state with near-original texture and colours requires thorough optimization of freezing operation. In this study, the research of the impact of pulsed electrotechnologies combined with osmotic pre-treatment on the structure of apple tissue, its freezing/thawing behaviour and texture quality, is provided.

Soil organic matter molecular composition and state of decomposition in three locations of the European Arctic

Increased mineralization of the organic matter (OM) stored in permafrost is expected to constitute the largest additional global warming potential from terrestrial ecosystems exposed to a warmer climate. Chemical composition of permafrost OM is thought to be a key factor controlling the sensitivity of decomposition to warming. Our objective was to characterise OM from permafrost soils of the European Arctic: two mineral soils—Adventdalen, Svalbard, Norway and Vorkuta, northwest Russia—and a “palsa” (ice-cored peat mound patterning in heterogeneous permafrost landscapes) soil in Neiden, northern Norway, in terms of molecular composition and state of decomposition. At all sites, the OM stored in the permafrost was at an advanced stage of decomposition, although somewhat less so in the palsa peat. By comparing permafrost and active layers, we found no consistent effect of depth or permafrost on soil organic matter (SOM) chemistry across sites. The permafrost-affected palsa peat displayed better preservation of plant material in the deeper layer, as indicated by increasing contribution of lignin carbon to total carbon with depth, associated to decreasing acid (Ac) to aldehyde (Al) ratio of the syringyl (S) and vanillyl (V) units, and increasing S/V and contribution of plant-derived sugars. By contrast, in Adventdalen, the Ac/Al ratio of lignin and the Alkyl C to O-alkyl C ratio in the NMR spectra increased with depth, which suggests less oxidized SOM in the active layer compared to the permafrost layer. In Vorkuta, SOM characteristics in the permafrost profile did not change substantially with depth, probably due to mixing of soil layers by cryoturbation. The composition and state of decomposition of SOM appeared to be site-specific, in particular bound to the prevailing organic or mineral nature of soil when attempting to predict the SOM proneness to degradation. The occurrence of processes such as palsa formation in organic soils and cryoturbation should be considered when up-scaling and predicting the responses of OM to climate change in arctic soils.

Archaeobotanical remains from inhumation graves in Finland, with special emphasis on a 16th century grave at Kappelinmäki, Lappeenranta

Plant remains from graves shed light on the usage of plants as part of the burial customs, economy or diet of the past. The aim of this interdisciplinary study was to examine what new information can be acquired from graves by combining archaeobotanical and pollen data with archaeological results. The study material consisted of soil samples from 158 graves of nine different archaeological sites in southern Finland, dated from the Iron Age to the 16th century. Archaeobotanical results from the graves were generally rather modest. However, remarkable results were gained from a 16th century grave at the Kappelinmäki cemetery in Kauskila, Lappeenranta. The grave gave evidence of the deceased's last meal, since a large number of raspberry seeds and some fish bones were discovered. Pollen analysis of the same grave gave evidence of funeral practices and ritual usage of plants. Due to local soil conditions, plant material was generally not preserved in the inhumation graves. Preserved plant material can be associated with the graves with well-preserved human bones and / or the graves containing plentiful metal artefacts.

The effects of different freeze-drying processes on the moisture content, color, and physical strength of roses and carnations

Freeze-drying is a relatively new preservation process for the preserved plant material industry. However, optimum freeze-drying procedures have been determined for very few flowers. This study evaluated the effects of different freezing times and vacuum-drying temperatures on color, moisture content, and stem and petal strengths of roses and carnations. Strength/stiffness was determined via force-deformation curves. The moisture content of freeze-dried flowers determines their longevity, and fewer changes in shape and color increases their aesthetic value. Vacuum-drying temperatures had more effect on the flowers than freezing time. Lower vacuum-drying temperatures resulted in flowers with color closer to fresh and control flowers, while higher vacuum-drying temperatures resulted in lower moisture contents and stronger/stiffer petals but more changes in color.

A test for the analogy of tropical domed peat deposits to “dulling up” sequences in coal beds—Preliminary results

Megascopic and microscopic characteristics of a domed peat deposit in Sarawak, Malaysia were examined to test their analogy to “dulling up” sequences in low-ash coal beds. Preliminary petrographic results show high concentrations (> 95%) of vitrinite precursor material for all peat types, but that fibrous peats in the upper central portion of the deposit contain more preserved plant material than peats toward the base and margins which, although more decomposed, contain large fragments (5–150 cm) of wood. These results present contradictory evidence in support of a dulling up model and suggests that modern tropical peat domes are perhaps poor petrographic analogues for dulling up sequences. This deposit would produce an “all bright” coal seam with bright vitrain bands of variable thickness and amount, set in bright, high vitrinite matrix.

Preservation of plant material by large scale sorption freeze‐drying

AbstractA large‐scale sealed system for freeze‐drying herbage is described. It utilizes the principle of sorption drying and is dependent upon the vapour pressure differential (VPD) between the herbage and the silica gel drying agent. Ice sublimes to vapour from the sample in a system operating at approximately – 10°C and the vapour is adsorbed by silica gel in an air stream recycled by a blower; equal masses (up to 50 kg each) of wet herbage and silica gel are used. The system is simple to construct and is relatively inexpensive.Approximately eight days drying time are needed to reduce moisture content from 90 to 10%. Twenty‐four different species or cultivars of both temperate and tropical grasses and legumes sampled at several stages of maturity have been dried in the system. When snap‐frozen herbage is freeze‐dried by this process the physical and chemical changes that otherwise occur when herbage is harvested and prepared for evaluation can be reduced and sufficient material can be obtained to permit animal feeding studies as well as chemical analyses.

A Pennsylvanian-Age Terrestrial Storm Deposit: Using Plant Fossils to Characterize the History and Process of Sediment Accumulation

A thin black shale overlying the B-coal underclay (in the Middle Pennsylvanian post-Pottsville strata of the Bernice Basin) contains a compression flora composed of large, prostrate, unidirectionally oriented lycopod trunks and randomly oriented pteridosperm stems. Analyses of modern log accumulations indicate that unidirectional trunk orientations can be produced by riverflood currents, volcanic blasts, and most high-energy windstorms. Since there are neither fluvial sediments nor ash deposits associated with the Bernice assemblage, this deposit is believed to have been formed by high-energy winds. Furthermore, this deposit is interpreted to be in situ because storm winds (and volcanic blasts) rarely have sufficient energy for the physical transport of large, intact tree trunks. The sedimentary history of the B-coal underclay can be determined from the successional changes in the species and plant part compositions (leaves, seeds, branches, trunks, etc.) of the preserved plant material. The underclay is an accretionary floodplain soil which accumulated as discrete increments during episodic floods. The sediments deposited with each flood incorporated the litter layer of the lycopod-pteridosperm forest which occupied this site. Ordinarily, the flood water would recede, and renewed root growth would destroy the primary sedimentary structures and the newly incorporated organic material. Because the bedding and forest litter are preserved in the top 5 cm of the underclay, root growth and silt deposition must have been terminated by the last flooding event. The site eventually became permanently inundated, and an organic-rich mud began to accumulate in the resulting floodplain lake. The lycopod-pteridosperm forest drowned and, at some later time, was blown down into the lake. The trunks are preserved on a single bedding plane in a 2-cm-thick, organic-rich lacustrine black shale. Continued organic accumulation in the lake resulted in the accumulation of a hypautochthonous peat which eventually was colonized by a peat-forming flora.

Preparation techniques and student evaluation of bioplastic specimen blocks for use in crop science teaching

Plastic specimen blocks enhance crop science lecture and laboratory teaching according to student reaction measured three semesters in the Department of Agronomy, University of Illinois. Students indicated that these visual aids are useful, interesting, important, and successful in promoting teaching objectives. Similar positive student responses to the use of plastic-embedded crop specimens were found among all classes and majors enrolled in the introductory crop science course. Agronomic specimens which have been successfully embedded include: seeds of weeds and crops, grass collars, flowers and typical leaves of plants, grass spikelets, plant inflorescences, ears and ear sections of corn, soybean pods, and nodulated soybean roots. Special “freeze dry” techniques are essential in preparing wet plant specimens for embedding since plastic resin does not mix with water. Advantages of preserving agronomic specimens in bioplastic blocks include: (a) minimum breakage because of fragile nature of dry specimens (b) easy stereomicroscopic examination, and (c) preservation of plant materials in natural color for repeated use.

The Archaeological Evidence for Manioc Cultivation: A Cautionary Note

In the humid tropics of the Americas, where preservation of plant materials is unlikely, archaeological evidence for manioc cultivation largely consists of artifacts which are similar to artifacts associated with manioc cultivation in the ethnographic record and which, by analogy, were similarly used in the prehistoric past. The validity of this inference by analogy is examined in terms of ceramic platters and stone grater teeth, two of the most commonly cited evidences for manioc cultivation.

Laminating Moth Wings and Larvae1

In most institutions there is a limitation on space. A process has been devised whereby reference material for certain groups of insects can be assembled in a compact unit (fig. 1). Fessenden (1949) described the preservation of plant material by lamination, and the preservation of both plants and insects in plastic blocks. His methods were complex and expensive.

Silage studies IX biochemical changes in microbe-free silage

If the aseptic plant material is regarded as a substrate for preservative microbial activity, it may be said that both the nitrogen and carbohydrate components undergo changes due to the influence of native enzymes in the plant material. These changes may very well be reflected in the microbial activity in a silage. It is interesting to compare the findings of this investigation, which show that during the days immediately after ensilage practically no changes take place when no bacteria are present. In a non-sterile ensilage, on the other hand, it is during this early stage that the briskest bacterial activity takes place. The chances of, say, an acid-forming microbial process actually lowering the pH in order that preservation of the material may take place are directly counteracted by the action of native enzymes of the vegetable material. During the days immediately after ensilage, however, if other conditions are favourable, microbial activity may clearly determine the whole course of events, and may possibly even inactivate the processes of the plant material itself. As is evident from the experiments described above, the activities inherent in the ensiled material itself are of no mean proportions. Further study of the mutual relationship of the ensilage and the various microbial fractions is therefore particularly necessary in order to be able to understand a number of processes of fundamental importance in biological preservation of plant material.