Barbara Adomas

Phytotoxicity of Sulfamethazine Soil Pollutant to Six Legume Plant Species

The effect of traces of sulfamethazine (SMZ) in soil (0.01, 0.1, 0.25, 1, 5, 15, and 20 mM) on cellular distribution of cytochrome c oxidase activity, shoot and root growth, and leachate electroconductivity was analyzed in germinating seeds of yellow lupin, pea, lentil, soybean, adzuki bean, and alfalfa. Results showed that a high activity of cytochrome c oxidase in mitochondria correlated with high seed vigor and viability. The appearance of necroses and root decay was associated with a decrease in the activity of mitochondrial cytochrome c oxidase but was accompanied by an increase in cytosolic cytochrome c oxidase activity. A short exposure period of seeds (3 and 6 d) to sulfamethazine did not influence germination. Elongation of roots and stems was more sensitive than germination rate as an indicator of soil contamination by sulfamethazine. Among all tested leguminous plants, yellow lupin was the most reliable bioindicator of SMZ contaminated soil.

Phytotoxicity of Sodium Chloride Towards Common Duckweed (Lemna Minor L.) and Yellow Lupin (Lupinus Luteus L.)

Abstract Salinity has adverse effects on plants and is one of the causes of environment degradation. Plants have developed many defensive mechanisms, protecting them from sodium chloride (NaCl), including accumulation of osmoprotective compounds, which maintain osmotic balance, protect cell structure and enzymes. In the current study, we investigated the effects of salinity resulting from a range of sodium chloride concentrations (from 0 to 400 mM) on the growth of common duckweed (Lemna minor L.) and yellow lupin (Lupinus luteus L.). Increasing concentration of sodium chloride decreased the area of common duckweed leaves. At the highest applied salt concentration, the decrease of leaf area was associated with leaf chlorosis. In yellow lupin, the increasing sodium chloride concentration inhibited root and stem elongation. The highest tested NaCl concentration of 400 mM completely stopped elongation of yellow lupin shoots. The content of cyclitols and soluble carbohydrates in plant tissues was evaluated as well. Cyclitols (D -chiro -inositol and D -pinitol), as well as soluble carbohydrates (glucose, fructose and sucrose) were detected in common duckweed tissues. Yellow lupin seedlings also contained cyclitols - D -pinitol, myo -inositol and D -chiro -inositol - and soluble carbohydrates - glucose, galactose and sucrose. The content of osmoprotectants in plant tissues, especially sucrose and cyclitols, increased with increasing concentration of sodium chloride in the soil. The results indicate that the content of cyclitols and soluble carbohydrates in plant tissues can be an indicator of plant response to salinity stress. Zasolenie wpływa niekorzystnie na roślinność i stanowi jedną z przyczyn degradacji środowiska wodnego i glebowego. Rośliny wykształciły wiele mechanizmów odporności na NaCl, jednym z nich może być akumulacja związków osmoprotekcyjnych, utrzymujących równowagę osmotyczną, chroniących struktury komórkowe i enzymy. W pracy badano wpływ zasolenia wywołanego różnymi stężeniami chlorku sodu (od 0 do 400 mM) na tempo wzrostu rzęsy drobnej (Lemna minor L.) i łubinu żółtego (Lupinus luteus L.). Ponadto w tkankach roślin oceniano zawartość cyklitoli i węglowodanów rozpuszczalnych. Wzrastające stężenie chlorku sodu zmniejszało powierzchnię liści rzęsy drobnej. W najwyższym z zastosowanych stężeń obok redukcji pola powierzchni liści obserwowano również intensywną chlorozę liści. Wzrastające stężenie chlorku sodu hamowało wzrost elongacyjny korzeni i łodyg łubinu żółtego. Najwyższe z badanych stężeń NaCl całkowicie hamowało wzrost elongacyjny łodyg łubinu żółtego. W tkankach rzęsy drobnej występowały cyklitole (D -chiro -inozytol i D -pinitol) oraz węglowodany rozpuszczalne (glukoza, fruktoza i sacharoza). Natomiast w siewkach łubinu żółtego występowały cyklitole (D -pinitol, myo -inozytol i D -chiro -inozytol) oraz węglowodany rozpuszczalne (glukoza, fruktoza, galaktoza i sacharoza). Wykazano, że wraz ze wzrostem stężenia chlorku sodu w podłożu wzrastała zawartość osmoprotektantów (cyklitoli i sacharozy) w tkankach. Badania wykazały, że cyklitole i węglowodany rozpuszczalne obecne w tkankach łubinu żółtego i rzęsy drobnej są dobrymi biomarkerami środowiska zanieczyszczonego chlorkiem sodu.

Tetracycline Accumulation in Pea Seedlings and its Effects on Proteome and Enzyme Activities

Among antibiotics, tetracyclines are the most commonly used and detected in the environment. In this study, the amount of tetracycline taken up from soil by pea seedlings was analyzed, identified its main site of accumulation in plants and determined also changes in the protein profile of pea. The study demonstrates that pea seedlings take up tetracycline from soil and transport the drug via roots to over-ground parts and then accumulate it in the youngest parts, such as upper stem and leaves. After the taken up of drug, the activity of guaiacol peroxidase is modified and changes in the profile of proteins, as determined by two-dimensional gel electrophoresis occur. The majority of proteins (∼40%) visualized possessed molecular weight between 25 and 37 kDa. Only 8% of the proteins had molecular weight lower than 20 kDa, and 2% greater than 75 kDa. The number of spots in the control samples was 194, which is less by 49 than at the concentration of 150 mg kg of soil. Isoflavone reductase was present only in seedlings growing with tetracycline. Tetracycline uptake from soil modify mainly the changes in biochemical processes connected with protein.

Content of biogenic amines in Lemna minor (common duckweed) growing in medium contaminated with tetracycline

Aquatic plants are continuously exposed to a variety of stress factors. No data on the impact of antibiotics on the biogenic amines in duckweed (Lemna minor) have been available so far, and such data could be significant, considering the ecological role of this plant in animal food chains. In the tissues of control (non-stressed) nine-day-old duckweed, the following biogenic amines were identified: tyramine, putrescine, cadaverine, spermidine and spermine. Based on the tetracycline contents and the computed EC values, the predicted toxicity units have been calculated. The obtained results demonstrated phytoxicity caused by tetracycline in relation to duckweed growth rate, yield and the contents of chlorophylls a and b. The carotenoid content was not modified by tetracycline. It was found that tetracycline as a water pollutant was a stress factor triggering an increase in the synthesis of amines. Tetracycline at 19, 39 and 78μM concentrations increased biogenic amine synthesis by 3.5 times. Although the content of tyramine increased fourteen times with the highest concentration of the drug (and of spermidine - only three-fold) the increase of spermidine was numerically the highest. Among the biogenic amines the most responsive to tetracycline were spermine and tyramine, while the least affected were putrescine and spermidine. Despite putrescine and spermidine being the least sensitive, their sum of contents increased five-fold compared to the control. These studies suggest that tetracycline in water reservoirs is taken up by L. minor as the antibiotic clearly modifies the metabolism of this plant and it may likely pose a risk.

Herbicide Phytotoxicity and Resistance to Herbicides in Legume Plants

Active substances in herbicides, just like in other pesticides, are chemical compounds synthesized in order to kill organisms which are harmful for cultivated plants. Therefore, they are toxins introduced on purpose by man into the environment. From the perspective of environmental protection, it is very significant that herbicides are most often applied directly into the soil to manage weeds. Since DDT and chloro-organic herbicides such as 2,4,5-T were withdrawn (in the 1970s) and since the EU regulations were unified for all its member countries, plant protection techniques have advanced considerably. Yet, pesticides, thus herbicides as well, continue to be a big group of xenobiotics periodically occurring at high levels in agroecosystems. These compounds infiltrate into related biocenoses from air, soil, water and food (Allinson & Morita, 1995; Kolpin et al., 1998; Adomas at al., 2008). Soil may become a reservoir of various pollutants, including herbicides. Herbicides remain active in soil for different periods. Paraquat has a relatively long half-life in soil (estimated at about 1000 days). The half-life of glyphosate in soil is only 10 to 100 days, and according to Monsanto the average half-life of this herbicide is 32 days (Hornsby et al., 1996; Monsanto, 2005). Remainders of persistent herbicides (e.g. atrazine, metribusin, and trifluralin) can stay in soil and destroy subsequent plantations a year or more after herbicides had been used. Herbicides from soil leach into surface water and ground water. The assessment of herbicides content in the aquifers in Iowa shows that 75% of herbicides (Kolpin et al., 1998), despite degradation, are still detected. From soil, water or air, herbicides get into crops (Adomas et al., 2008). When pesticides are applied, acceptable remainders of active substances (MRL) can often be detected in cultivated plants. Depending on physicochemical properties of the active substances of pesticides and the ways of their detoxification, some of these pollutants tend to increase concentration while passing through organisms of higher trophic levels. It can lead to a significant bioaccumulation of toxins in the food chains (Allinson & Morita, 1995; Dinis-Oliveira et al., 2006). No doubt therefore, monitoring of herbicide (including desiccant) residues in cultivated plants is needed, so that people and environment can be safe. Moreover, application of herbicide desiccants modifies physiological properties of seeds and may thus lead to delayed problems, becoming evident long after the treatment.