Vassilios Triantafyllidis

Effects of Presowing Pulsed Electromagnetic Treatment of Tomato Seed on Growth, Yield, and Lycopene Content

The use of magnetic field as a presowing treatment has been adopted by researchers as a new environmental friendly technique. The aim of this study was to determine the effect of magnetic field exposure on tomato seeds covering a range of parameters such as transplanting percentage, plant height, shoot diameter, number of leaves per plant, fresh weight, dry weight, number of flowers, yield, and lycopene content. Pulsed electromagnetic field was used for 0, 5, 10, and 15 minutes as a presowing treatment of tomato seeds in a field experiment for two years. Papimi device (amplitude on the order of 12.5 mT) has been used. The use of pulsed electromagnetic field as a presowing treatment was found to enhance plant growth in tomato plants at certain duration of exposure. Magnetic field treatments and especially the exposure of 10 and 15 minutes gave the best results in all measurements, except plant height and lycopene content. Yield per plant was higher in magnetic field treatments, compared to control. MF-15 treatment yield was 80.93% higher than control treatment. Lycopene content was higher in magnetic field treatments, although values showed no statistically significant differences.

Spatiotemporal Variation and Risk Assessment of Pesticides in Water of the Lower Catchment Basin of Acheloos River, Western Greece

A three-year monitoring survey (March 2005–February 2008) was conducted to investigate, on monthly basis, the presence of thirty pesticides belonging to various categories and metabolites, in Acheloos River (Western Greece), one of the most important water resources in Greece. Six sampling stations along the river were established. Water analyses were performed using solid-phase extraction combined with gas chromatography with flame thermionic detector and mass spectrometry. Statistical analysis using one-way ANOVA and Duncans multiple range test (P < 0.05) was used to compare annual mean concentrations of pesticides, seasonal and spatial distribution. In general, the highest mean concentrations of the pesticides were recorded at the three stations downstream. The greatest average concentrations were determined during spring and summer in agreement with the pesticide application period. The observed lower concentrations after 2006 reflect the land-use change because of the elimination of tobacco, the main cultivation of the area for many decades. The compounds most frequently detected were diazinon (78.6%), DEA (69.3%), and fenthion (52.6%). Environmental risk assessment using risk quotient (RQ) approach showed high risk for six insecticides in 2005 and one in 2007. A compliance with the European Environmental Quality Standards (EQS) was observed for the priority pesticides.

Imidacloprid losses in surface runoff from plots cultivated with tobacco

The loss of imidacloprid, a systemic insecticide, was determined in runoff water from loamy soil plots of various surface slopes cultivated with tobacco over a period of 174 days. Conditions were selected to simulate agricultural practices employed in the Mediterranean region. The surface slopes of plots were 0, 2.5, 5, 7.5, and 10%, and both cultivated and uncultivated (control) areas were monitored simultaneously. The cumulative losses of imidacloprid in surface runoff from tilled and untilled plots with a slope of 10% were estimated at 0.076% and 0.131% of the initial applied active ingredient, respectively, while for the plots with a slope of 0%, they were 0.003% and 0.005%. Analyses of soil samples for a 110 day period made it possible to study the kinetics of pesticide residue decrease. The average half-life was 17.8 days in bare soil and 16.9 days in tobacco-cultivated plots.

Evaluation of Mobility and Dissipation of Mefenoxam and Pendimethalin by Application of CSTR Model and Field Experiments Using Bare and Tobacco Tilled Soil Columns

The soil mobility and dissipation of two pesticides with different physicochemical properties, namely mefenoxam, a systemic fungicide, and pendimethalin a selective herbicide, were determined in bare and tobacco tilled soil columns, which were installed in field conditions for over 125 days. Soil samples were collected at specific time intervals for a 125-day period and the rate of pesticide dissipation and leaching through the soil column was studied. The dissipation half-lives of mefenoxam from the top soil layer in tilled and bare soil columns were estimated at 10.3 and 13.1 days, respectively, while the corresponding half-lives for pendimethalin were 26.7 and 27.5 days, respectively. The dissipation of mefenoxam and pendimethalin from the top soil in tobacco cultivation was faster in comparison with bare soil; however, 120 days after their application, both pesticide residues were detected in the soil. Maximum concentrations of mefenoxam and pendimethalin were observed on the 15th and 33rd day, respectively, in the soil layer of 5–10 cm depth and on the 30th day and 63rd day, respectively, in the soil layer of 10–15 cm depth. Higher concentrations were observed in bare soil columns. The leaching of both pesticides was simulated with the continuous stirred tank reactor (CSTR) in series model. The simulated peak concentration and peak time for both pesticides fitted reasonably well to the experimental values.

Corrigendum to “Effects of Presowing Pulsed Electromagnetic Treatment of Tomato Seed on Growth, Yield, and Lycopene Content”

[This corrects the article DOI: 10.1155/2014/369745.].