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Methyl jasmonate (MJ) is a widely occurring molecule. Since it is synthesized constitutively, its presence is substantial to plant normal growth and development. Moreover, its elevated concentration detected under abiotic and biotic stress conditions seems to be crucial to plant in reacting to adverse events and its ability to survive. Because of the sophisticated biochemical machinery inside the plant body, MJ, among other molecules, helps the plant to adopt to the surrounding environmental changes and is involved in its defense system.
Environmental studies conducted after the 2010 flood in the middle Vistula River Valley focused on assessment of the physicochemical properties of soil (0-20 cm) sampled from horticultural plantations (2493 samples). Soil pHKCl as well as the content of available P, K and Mg forms were determined. Selected samples (48) were analysed for the content of heavy metals (Cu, Zn, Cd, Pb, Cr, Ni, As, Hg), mineral N, S-SO4, salinity and dry mass. The tested soil pH ranged from acid to neutral; the phosphorus content was in the average range, while the content of available potassium was 161.0 mg K kg-1 and that of available magnesium exhibited the value of 160.5 mg Mg kg-1. The mean value of pHKCl and available P were not elevated in the flooded soils versus the same soils before the flood, while the available K and Mg were higher. The content of mineral nitrogen and sulphate sulphur as well as the salinity level were only slightly dependent on the soil agronomic category and soil pH. The content of heavy metals in the soil was higher than before the flood, but did not exceed natural values. The analyses did not demonstrate any significant deterioration of the physicochemical parameters of soils after the 2010 flood, which could negatively affect the quality and yield of cultivated fruit trees and shrubs.
The present study deals with biochemical and physiological methods for assessment of the optimal nutrient supply for the growth and development of garden rocket (Eruca sativa Mill.), edible vegetable. Two nitrate (0.3; 0.6 g N dm⁻³ of medium) and three potassium doses (0.3; 0.6; 0.9 g K dm⁻³ of medium) in the form of sulphate or chloride were examined. At the higher nitrate dose and the sulphate form of potassium the intense green colour of leaves, higher content of nitrates, flavonoids, L-ascorbic acid and lower carbohydrates content correlated with elevated growth parameters, e.g. the number of leaves and partially plant fresh weight. The proline and anthocyanin contents weakly diversified the nutrient supply. Despite the lack of modification in the photosynthetic pigment concentration, the chlorophyll fluorescence parameters were significantly improved when the higher nitrate dose accompanied the sulphate form of potassium (higher values of fluorescence decrease, maximum quantum efficiency of PSII photochemistry in the dark-adapted state, photochemical quenching and lower values of the fraction of absorbed light energy not used for photochemistry). The biochemical and photosynthetic parameters corresponding to the morphological characteristics (leaf colour, number of leaves and plant fresh weight) indicated that better nutrient conditions were provided to plants under the combined fertilization of the higher nitrate dose and the sulphate form of potassium.
Maize seedlings grown in a nutrient solution were treated with Cd (50, 100 μM) or Cu (50, 100 μM). Roots and separated leaf sections (from the youngest–– basal, through the middle––mature, to the oldest––apical) were analysed. Shoot and root fresh weight, and root net growth rates were reduced significantly after Cu application in comparison to Cd. Copper (50, 100 μM) and cadmium (100 μM) decreased the sum of chlorophyll and total carotenoid pools mostly in mature and old leaf sections. The concentration of Cu and Cd increased in the old and mature leaf sections. Analysis of organic acids showed that both metals differently influenced the lowmolecular-weight organic acids (LMWOAs) content in maize leaf sections. In mature sections, the excess Cu increased the succinate and tartrate contents, whereas in the young ones mainly the tartrate level was elevated. Cadmium elevated citrate accumulation in mature and old sections, compared to the control plants. Malate, the main LMWOA in maize leaves, increased only after addition of 100 μM of Cd (mature and old sections) or 50 μM of Cu (old sections). Analysis of LMWOAs in roots showed that the excess of Cd or Cu induced higher accumulation of tartrate and malate and, additionally, copper increased the citrate content.
The aim of the experiment, conducted from 1973 to 1999, was to determine the effect of long-term fertilization with liquid manure (annual and biennial) and with mineral fertilizers on selected physicochemical and chemical properties of soil, i.e., the content of phosphorus, potassium, magnesium, sulphate sulphur, iron, manganese, pHKCl and organic carbon. Fertilization with liquid manure was observed to have resulted in a significant reduction in the content of soil-available phosphorus in comparison to fertilization with NPK. Fertilization with both liquid manure and NPK led to a significant increase in the content of available potassium and magnesium in the soil profile. The highest amounts of S-SO4 were reported from the topsoil layer, irrespective of the type of fertilizer applied. Fertilization with liquid manure and NPK caused an irregular rise in the content of iron soluble in 1 M HCl in the soil, whereas the content of manganese increased slightly and irregularly in response to the fertilization applied. A negligible rise in pHKCl of the topsoil layer was observed at annual application of increasing doses of liquid manure. It was reported that fertilization with liquid manure led to a steady rise in the organic carbon content in the soil profile.
The aim of the experiment was to assess the effect of long-term fertilization with liquid manure applied annually and biennially and with mineral fertilizers on selected sorption properties of soil, i.e. the content of exchangeable magnesium, potassium, calcium, sodium and as well as the value of hydrolytic acidity, sorption capacity and base cation saturation ratio. It was found that fertilization with liquid manure, in contrast to NPK application (N as NH4NO3, P as triple super phosphate, K as KCl), led to a significant rise in the content of exchangeable magnesium in soil, whereas application of liquid manure or mineral fertilizers contributed to a significant increase in the potassium content in soil. Application of liquid manure did not cause significant changes in the value of hydrolytic acidity between the lowest and the highest dose used, while mineral fertilization contributed to an increase in the value of hydrolytic acidity. Application of liquid manure reduced the value of hydrolytic acidity as deep as the third layer of the soil profile. Fertilization with liquid manure and mineral fertilizers did not affect the content of exchangeable calcium in the whole soil profile, although the calcium content in the soil profile increased to the 51-75 cm layer. Application of liquid manure and NPK did not alter significantly the content of exchangeable sodium in soil. Upon application of both liquid manure and NPK, no significant changes were observed in the total base exchangeable cations in soil (S) or in the sorption complex saturation (V). However, S and V significantly increased along the depth of sampling. It was found that fertilization with both liquid manure and mineral fertilizers did not induce substantial changes in the soil sorption capacity, although there was an increase in the total sorption capacity in two layers (51-75 cm and 76-100 cm) of the soil profile.
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