0000000000385833

AUTHOR

Andis Karlsons

Physiological Performance of a Coastal Marsh Plant Hydrocotyle vulgaris in Natural Conditions in Relation to Mineral Nutrition and Mycorrhizal Symbiosis

Abstract Fluctuating soil salinity and competition for light are the main factors affecting plant distribution and performance in coastal salt marshes. The aim of the present study was to assess plant performance by means of non-destructive instrumental methods in a highly heterogeneous natural habitat. More specifically, environmental factors affecting growth and physiological performance of a clonal plant Hydrocotyle vulgaris L. were investigated. Changes in soil salinity, soil mineral characteristics, leaf nutrient concentrations, morphological parameters, chlorophyll fluorescence, and mycorrhizal symbiosis were analysed in different experimental plots of naturally growing H. vulgaris pl…

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Minerālās barošanās adaptīvie mehānismi un minerālelementu nodrošinājuma īpatnības jūras piekrastes augiem

Elektroniskā versija nesatur pielikumus

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Physiological Responses of Wetland Species Rumex Hydrolapathum to Increased Concentration of Biogenous Heavy Metals Zn and Mn in Substrate

Abstract The aim of the present study was to determine if individuals of Rumex hydrolapathum Huds native to saline wetlands are able to tolerate high concentration of biogenous heavy metals Zn and Mn in substrate and to accumulate high concentration of these metals in aboveground parts. Plant physiological status was monitored by using non-destructive analysis of chlorophyll and chlorophyll a fluorescence. R. hydrolapathum plants accumulated up to 1840 mg·kg−1 Zn and 6400 mg·kg−1 Mn in older leaves. The usefulness of monitoring changes in chlorophyll concentration and chlorophyll a fluorescence parameters to predict physiological response of R. hydrolapathum plants to excess Zn and Mn was n…

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Light Conditions Affect NaCl-Induced Physiological Responses in a Clonal Plant Species Hydrocotyle vulgaris

Abstract In order to understand if differences in light conditions can affect responses of a clonal plant species to increased soil salinity, the long-term effect of two substrate concentrations of NaCl on leaf growth, clonal plasticity and oxidative enzyme (peroxidase and polyphenol oxidase) activity in Hydrocotyle vulgaris L. plants grown at low, moderate and high light conditions was studied. H. vulgaris appeared to be a shade-tolerant species, since both leaf blade and petiole growth was inhibited at low light intensity. At low light intensity, H. vulgaris plants represented characteristics of halophytes with significant stimulation of leaf blade and petiole growth by NaCl, especially a…

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DYNAMICS OF SOIL NUTRIENT STATUS OF HIGHBUSH BLUEBERRY IN LATVIA, 2006-2017

In Latvia, the first commercial highbush blueberry (Vaccinium corymbosum L.) plantings have been established on a few hectares at the end of the 1990th. Since then, a remarkable growth has noticed and today the total cultivated area reaches 280 hectares. An increasing market demand for fresh and processed berries provides a future upward trend in the development of blueberry crop in Latvia. In general, blueberry is a highly specialized crop that has definite soil agrochemical and climatic requirements. There are two main soil types used for blueberry cultivation in Latvia: well-drained acid sandy soils with high organic matter content and sphagnum peat soils. Evaluation and management of pl…

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Vermicompost from municipal sewage sludge affects growth and mineral nutrition of winter rye (Secale cereale) plants

ABSTRACTThe aim of the study was to investigate sewage sludge vermicompost application effects on growth and mineral nutrition of winter rye (Secale cereale L.) plants as compared to two initial levels of mineral nutrient availability, pure sand and sand enriched with inorganic nutrients at the optimal level. Addition of sewage sludge vermicompost significantly inhibited rye seed germination at 20 to 50% sand substitution independently on mineral nutrient supplement. Growth inhibition was evident at early stages of plant development. However, at the later stages, sewage sludge vermicompost acted both as mineral fertilizer and plant growth-promoting agent. Significant stimulation of mineral …

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Salinity-induced responses and resistance in Trifolium repens L.

Abstract White clover ( Trifolium repens L.) is a commonly cultivated legume with good ground cover potential often used with companion grass species in urban grassed areas. The effect of increased soil salinity on plant growth is an urgent problem in cities where NaCl is used as a de-icing material. The aim of this research was to examine the effect of different salinity levels and K supply-induced responses and tolerance in the T. repens L. variety ‘Daile’, a variety which is used in urban greenery. To analyze the impact of increased soil salinity and the antagonistic effect of K, the effect of gradually increasing NaCl (0, 20, 40, 60, 80, 100 mM) and K (+0, +100, +200, +300 mg/L) levels …

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Wild Plants from Coastal Habitats as a Potential Resource for Soil Remediation

The aim of the present review is to stimulate an interest in experimental exploration of native coastal plants as a valuable resource for development of and use in environmental remediation technologies. An attempt is made to analyze wild plant species from different coastal habitats in respect to the functional properties useful for soil remediation purposes. Several plant species from a number of coastal plant genera are described as potential models for further studies aimed at practical environmental phytoremediation, including Armeria maritima, Rumex hydrolapathum, Ranunculus sceleratus, Anthyllis maritima, Alyssum montanum subsp. gmelinii, and Sedum maximum. It is concluded that a lar…

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ASSESSMENT OF THE IMPACT OF VERMICOMPOST AND PEAT EXTRACTS ON NUTRIENT ACCUMULATION IN TUBERS AND POTATO YIELD

Investigations on the potential beneficial effect of humic substances on crop plant cultivation under extremely diverse soil and climatic conditions is of global character, thereby knowledge obtained on the basis of local investigations are of great importance world-wide. The aim of the research was to evaluate the effect of different application methods (seed tuber treatment and foliar application) of commercially-produced peat and vermicompost extracts on nutrient uptake in tubers and yield of potato ( Solanum tuberosum L.) using field experiments in organic farming system with potato variety ‘Borodjanskij Rozovij’. The tested extracts from the organic products included: peat extract (K45…

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Effect of Vermicompost Extract and Vermicompost-Derived Humic Acids on Seed Germination and Seedling Growth of Hemp

Abstract Hemp (Cannabis sativa L.) cultivars grown for industrial use have recently emerged as a sustainable alternative source of industrial fibre and bioenergy, and is a highly valuable food and animal feed resource. The aim of the present study was to evaluate the effect of vermicompost extract, vermicompost mineral nutrient composition, and vermicompost-derived humic and fulvic acids on seed germination and growth of hemp seedlings. In general, separate application of all vermicompost components stimulated seed germination and hypocotyl and radicle growth, as well as increased chlorophyll concentration in cotyledons. Effective concentration range and the degree of stimulation varied sig…

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