Bryophytes as a safeguard of fruits from postharvest fungal diseases: A Review

Postharvest losses from fungal pathogens to essential fruits and vegetables are enormous and alarming. Orthodox synthetic fungicides are being used as a regular practice to restrict these losses. However, now by knowing the hazards of these chemical-based fungicides, the situation demands alternative green technology. Consequently, many angiosperms plant extracts have been evaluated for their antifungal nature and achieved substantial success. However, the second most prevalent flora on land, i.e. bryophytes, have been scarcely used and somewhat remain neglected besides their remarkable thallus organization, water relations and antimicrobial potential. For postharvest fungus control, these bryophytes, the first land plants' extracts to be researched and promoted due to concerns about drug resistance, nephrotoxicity and biomagnification related to current synthetic fungicides. Since these amphibious plants have their unique protective mechanism against fungal or bacterial attacks due to their unique phytochemistry, therefore have great potential to be used as eco-friendly fungicides. Considering these factors, this article seeks to direct the attention of interested researchers toward the relatively accessible but vast underutilised bryo-diversity to investigate their remarkable potential as postharvest antifungal agents first in laboratories and then on a commercial scale in the future.

Settlement characteristics of The Emerald Network "Khukhra" and "Riabyna" objects in Sumy region

The current state of biotope’s vegetation cover by natural and spontaneous origin of the Khukhra and Riabyna river valleys was researched, which are left-bank tributaries of the Vorskla river, as fragments of the preserved landscape within one of the western spurs of the Central Russian Upland. They are listed as perspective objects of the Emerald Network — Riabyna river valley in Sumy region (UA0000427) and Khukhra river valley in Sumy region (UA0000429). The obtained new data on environmental significance are data for the primary database formation in the monitoring organization of these territorial objects. The researched areas are mainly floodplains, small segments of pine terraces and slope’s fragments of these rivers native banks. The presence numbers of biotopes from Resolution 4 of the Berne Convention (C1.222; C1.223; C1.224, C1.32; C1.33; C1.4; C2.33; C2.34; C3.51; D5.2; E2.2; E5.4; F9.1; G1.11; G1.21; G1.22; G1.A4; G1.A1) are given for both explored objects, in addition, for the valley of the Riabyna river are indicated E1.3; E3.4, and for the Khukhra river — C3.4; E1.2. We have not confirmed the existence of such biotopes as C3.4, E1.3, C1.4 for these objects. Also, the presence of Sarmatian-type pine forests (G3.4232) was noted, which are timed to the elevations of pine terraces. Biotopes with constant excessive moisture are ubiquitous in the waters of low-flow artificial ponds. Eutrophic and mesotrophic vegetation of slow-flowing waters often occurs in shallow water along riverbeds. Biotopes groups of dwarf annual amphibious plants were observed only in fragments. Lowland swamps with sedge thickets without stagnant water are widespread in the floodplain, although they occupy small areas. Biotopes flooded pasture and hay meadows are a variety of options coenotic (herbaceous and cereal, wet and moist high-grass meadows). Biotopes of riparian shrubs, willow and willow-poplar floodplain forests are distributed in small fragments in the riverbed of floodplains. Mixed riparian floodplain and gallery forests occur in low-lying areas at the transition from the floodplain to the pine terrace. In general, shrub and forest vegetation on the terraces of these rivers are currently quite limited and fragmentary. Due to the reduction in the use of hayfields, in the floodplain the presence of indigenous forest remnants is quite relevant, which should be a source for their restoration in large areas. Important environmental object in these areas, as part of the Emerald Network is the local population of Ostericum palustre, and in the valley of the Khukhra river discovered a large population.

The molecular framework of heterophylly in Callitriche palustris L. differs from that in other amphibious plants

Heterophylly refers to the development of different leaf forms in a single plant depending on the environmental conditions. It is often observed in amphibious aquatic plants that can grow under aerial and submerged conditions. Although heterophylly is well recognized in aquatic plants, the associated developmental mechanisms and the molecular basis remain unclear. In this study, we analyzed heterophyllous leaf formation in an aquatic plant, Callitriche palustris, to clarify the underlying developmental and molecular mechanisms. Morphological analyses revealed extensive cell elongation and the rearrangement of cortical microtubules in the elongated submerged leaves of C. palustris. Our observations also suggested that gibberellin, ethylene, and abscisic acid regulate the formation of submerged leaves. However, the perturbation of one or more of the hormones was insufficient to induce the formation of submerged leaves under aerial conditions. Finally, we analyzed gene expression changes during aerial and submerged leaf development and narrowed down the candidate genes controlling heterophylly via transcriptomic comparisons, including a comparison with a closely related terrestrial species. We revealed that the molecular mechanism regulating heterophylly in C. palustris is associated with complex hormonal changes and diverse transcription factor gene expression profiles, which differs from the corresponding mechanisms in previously investigated amphibious plants.

Probing the Response of the Amphibious Plant Butomus umbellatus to Nutrient Enrichment and Shading by Integrating Eco-Physiological With Metabolomic Analyses

Amphibious plants, living in land-water ecotones, have to cope with challenging and continuously changing growth conditions in their habitats with respect to nutrient and light availability. They have thus evolved a variety of mechanisms to tolerate and adapt to these changes. Therefore, the study of these plants is a major area of ecophysiology and environmental ecological research. However, our understanding of their capacity for physiological adaptation and tolerance remains limited and requires systemic approaches for comprehensive analyses. To this end, in this study, we have conducted a mesocosm experiment to analyze the response of Butomus umbellatus, a common amphibious species in Denmark, to nutrient enrichment and shading. Our study follows a systematic integration of morphological (including plant height, leaf number, and biomass accumulation), ecophysiological (photosynthesis-irradiance responses, leaf pigment content, and C and N content in plant organs), and leaf metabolomic measurements using gas chromatography-mass spectrometry (39 mainly primary metabolites), based on bioinformatic methods. No studies of this type have been previously reported for this plant species. We observed that B. umbellatus responds to nutrient enrichment and light reduction through different mechanisms and were able to identify its nutrient enrichment acclimation threshold within the applied nutrient gradient. Up to that threshold, the morpho-physiological response to nutrient enrichment was profound, indicating fast-growing trends (higher growth rates and biomass accumulation), but only few parameters changed significantly from light to shade [specific leaf area (SLA); quantum yield (φ)]. Metabolomic analysis supported the morpho-physiological results regarding nutrient overloading, indicating also subtle changes due to shading not directly apparent in the other measurements. The combined profile analysis revealed leaf metabolite and morpho-physiological parameter associations. In this context, leaf lactate, currently of uncertain role in higher plants, emerged as a shading acclimation biomarker, along with SLA and φ. The study enhances both the ecophysiology methodological toolbox and our knowledge of the adaptive capacity of amphibious species. It demonstrates that the educated combination of physiological with metabolomic measurements using bioinformatic approaches is a promising approach for ecophysiology research, enabling the elucidation of discriminatory metabolic shifts to be used for early diagnosis and even prognosis of natural ecosystem responses to climate change.

Heterophylly: Phenotypic Plasticity of Leaf Shape in Aquatic and Amphibious Plants

Leaves show great diversity in shape, size, and color in nature. Interestingly, many plant species have the ability to alter their leaf shape in response to their surrounding environment. This phenomenon is termed heterophylly, and is thought to be an adaptive feature to environmental heterogeneity in many cases. Heterophylly is widespread among land plants, and is especially dominant in aquatic and amphibious plants. Revealing the mechanisms underlying heterophylly would provide valuable insight into the interaction between environmental conditions and plant development. Here, we review the history and recent progress of research on heterophylly in aquatic and amphibious plants.

Development of a wetland plant indicator list to inform the delineation of wetlands in New South Wales

Wetlands experience fluctuating water levels, so their extent varies spatially and temporally. This characteristic is widespread and likely to increase as global temperatures and evaporation rates increase. The temporary nature of wetlands can confound where a wetland begins and ends, resulting in unreliable mapping and determination of wetland areas for inventory, planning or monitoring purposes. The occurrence of plants that rely on the presence of water for part or all of their life history can be a reliable way to determine the extent of water-affected ecosystems. A wetland plant indicator list (WPIL) could enable more accurate mapping and provide a tool for on-ground validation of wetland boundaries. However, this introduces the problem of the definition of ‘wetland plant’, especially with species that can tolerate, or require, water level fluctuation, and that respond to flooding or drought by adjusting their morphology or phenology (i.e. ‘amphibious’ plants and those that grow only during drawdown). In this study we developed a WPIL through a process of expert elicitation. The expert decisions were compared and standardised for each species. It is envisaged that this work will lead to a comprehensive listing of wetland plants for Australia for the purposes of planning, mapping and management.

Updated checklist of aquatic macrophytes from Northern Brazil

Field collection and herbaria data did not allow to quantify the diversity of aquatic plants from Northern Brazil, so we could not detect biogeographic patterns. Therefore, our objectives were to identify and quantify the aquatic macrophytes of North Brazilian states, analyzing herbaria data plataforms (SpeciesLink and Flora do Brasil). The checklist was produced by bibliographic search (articles published between 1980 and 2000), herbaria collections of the platforms SpeciesLink and Flora do Brasil and field expeditions, where we utilized asystematic sampling. We also analyzed the floristic similarity of aquatic macrophytes among Northern Brazil, wetlands of distinct Brazilian regions and the Neotropics. We recorded 539 species, of which 48 are endemic to Brazil. The states with highest number of species were Amazonas and Pará, independently on platform. The most represented families were Poaceae (89 species), Podostemaceae (55), Cyperaceae (50) and Fabaceae (47). We highlight the unprecedent richness of Podostemaceae, due to our own field collection efforts on favorable habitats, 25 species being endemic. Emergent and/or amphibious plants (515) were dominant in total species richness and were best represented in lotic habitats. We found significant differences in richness and floristics among states, obtained from the platforms. There is floristic similarity among Northern states and other Brazilian wetlands. In conclusion, we observed a rich aquatic flora in Northern Brazil, in spite of scarcity of records for Acre, Rondonia and Tocantins; we highlight the unprecedent number of endemic species of Podostemaceae (25) and contrasting richness between SpeciesLink and Flora do Brasil.