Search results for " Botany"

Epiphytic communities of open habitats in the western Tian-Shan Mts (Middle Asia: Kyrgyzstan)

2016

The paper presents the results of bryosociological research conducted on the epiphytic vegetation in the western Tian-Shan Mountains in 2013. The surveys on epiphytic bryophyte and lichen communities were done on 115 sites with different quantity of trees (solitary, in alleys or wood plots along river valleys) distributed in several mountain ranges within study area. In total 21 epiphytic moss species were found during research which composes characteristic species combinations making apparent difference between associations. As a result of field research and numerical analyses, three separate groups of samples corresponding to seven associations and one community within three alliances: Ul…

Effect of weak magnetic fields on the in vitro propagation of Genista aetnensis (Raf. Ex Biv.) Dc.

2017

Over the years, many studies have emphasized the importance of the magnetic fields (MF), used as a safe alternative choice to improve agricultural production. The induction effect of different magnetic fields varies depending on the species, explants typology, intensity of magnetic field and period of exposure. The aim of the present study was to investigate the application of a continuous magnetic field induction, at different exposure times, as a production enhancement for in vitro culture of Genista aetnensis, an endemic shrub commonly named 'Mount Etna broom'. An in vitro protocol has been settled for the conservation of the species. Plantlets cultured onto a solified Murashige and Skoo…

2020

DnaK3, a highly conserved cyanobacterial chaperone of the Hsp70 family, binds to cyanobacterial thylakoid membranes, and an involvement of DnaK3 in the biogenesis of thylakoid membranes has been suggested. As shown here, light triggers synthesis of DnaK3 in the cyanobacterium Synechocystis sp. PCC 6803, which links DnaK3 to the biogenesis of thylakoid membranes and to photosynthetic processes. In a DnaK3 depleted strain, the photosystem content is reduced and the photosystem II activity is impaired, whereas photosystem I is regular active. An impact of DnaK3 on the activity of other thylakoid membrane complexes involved in electron transfer is indicated. In conclusion, DnaK3 is a versatile …

First report of Diplodia fraxini causing dieback of Fraxinus angustifolia in Spain

2018

Root architectural traits of rooted cuttings of two fig cultivars: Treatments with arbuscular mycorrhizal fungi formulation

2021

Abstract Many fruit tree species develop symbioses relationships with mycorrhizal fungi by which they improve their efficiency in water and nutrient uptake and, in turn, increase their vegetative growth and productivity, particularly under stressful environments. These benefits origin from the effects that mycorrhizal determined on the root architecture, morphology and physiology. Usually, few attentions has been devoted to the tree root structure and function, especially, in fig plants during their growth phase in the nursery. Recently, several root traits or phenes have been reported as fundamental for the root functions such as the root length ratio (plant’s potential for the exploitatio…

Geometric analysis of intrusive growth of wood fibres in Robinia pseudoacacia

2018

ABSTRACT All cell types of the secondary xylem arise from the meristematic cells (initials) of the vascular cambium and grow under mechanical constraints emerging from the circular-symmetrical geometry that characterises many tree trunks. The course of intrusive growth of cambial initials has been elucidated, but is yet to be described in the case of xylem fibres. This study explains the geometry of intrusive growth of the secondary xylem fibres in the trunk of Robinia pseudoacacia. Long series of serial semi-thin sections of the vascular cambium and the differentiating secondary xylem were analysed. Since fibres grow in close vicinity to expanding cells of the derivatives of the vascular c…

Preparation of Samples for Characterization of Arbuscular Mycorrhizal Fungi

2020

Arbuscular mycorrhizal fungi (AMF) are an important element of the plant microbiome as they establish an endosymbiotic relationship with the roots of most plant species. This association enhances access to nutrients and water for plants, and provides the fungus with plant-derived organic carbon. In this chapter, I describe a range of methods to work with AMF including: soil sampling; isolation of AMF propagules (spores, sporocarps, roots, and mycelium) by a wet sieving and centrifugation in a sucrose solution; trap (from field soil with AMF spores) and one-species pot cultures (from AMF spores divided into morphotypes); staining of mycorrhizae in plant roots; and production of diagnostic sl…

2020

Fucoxanthin and its derivatives are the main light-harvesting pigments in the photosynthetic apparatus of many chromalveolate algae and represent the most abundant carotenoids in the world's oceans, thus being major facilitators of marine primary production. A central step in fucoxanthin biosynthesis that has been elusive so far is the conversion of violaxanthin to neoxanthin. Here, we show that in chromalveolates, this reaction is catalyzed by violaxanthin de-epoxidase-like (VDL) proteins and that VDL is also involved in the formation of other light-harvesting carotenoids such as peridinin or vaucheriaxanthin. VDL is closely related to the photoprotective enzyme violaxanthin de-epoxidase t…

Polyamine Biosynthesis Engineering as a Tool to Improve Plant Resistance to Abiotic Stress

2015

Polyamines (PAs) are small polycationic molecules which are present in all living organisms. PAs have been involved in a wide array of metabolic plant processes, extending from development to stress protection. Most of this knowledge has been achieved through the observation of PA homeostasis and manipulation of plant PA levels mediated by different approaches. This chapter summarizes the approaches undertaken to demonstrate the relationship between PAs and the stress response and, in particular, how the genetic manipulation of polyamine levels has evolved in a useful tool for the enhancement of plant stress tolerance in many species, including crops. This chapter also includes the most rec…

Studying the Function of the Phosphorylated Pathway of Serine Biosynthesis in Arabidopsis thaliana

2017

Photorespiration is an essential pathway in photosynthetic organisms and is particularly important to detoxify and recycle 2-phosphoglycolate (2-PG), a by-product of oxygenic photosynthesis. The enzymes that catalyze the reactions in the photorespiratory core cycle and closely associated pathways have been identified; however, open questions remain concerning the metabolic network in which photorespiration is embedded. The amino acid serine represents one of the major intermediates in the photorespiratory pathway and photorespiration is thought to be the major source of serine in plants. The restriction of photorespiration to autotrophic cells raises questions concerning the source of serin…