Suchergebnisse

The purpose of this research was to determine the residue analysis of difenoconazole in apple fruits from Resen region, Republic of Macedonia. Analyzed were two varieties of apples, Golden Delicious and Idared. Samples were taken from two different locations in Resen in the year 2016. Difenoconazole analysis was performed with liquid chromatography-tandem mass spectrometry (LC-MS/MS) after a previous extraction of residue by applying the QuEChERS method. The obtained concentrations of residues of difenoconazole are compared with the maximum residue limit regulated by the Macedonian legislation. Analyses showed that the concentration of difenoconazole in both varieties of apples from two different locations is in the range of 0.01 to 0.41 mg/kg. In certain development phase of the apple fruits the concentration reaches 80 times lower concentration than the maximum limit. The data show that apple fruits can be safely consumed according to the recommended maximum residue limit (MRL) for difenoconazole in apples (0.8 mg/kg). Statistical processing of the data suggests that there is no significant difference between samples but presence of difenoconazole in apple fruits from both locations is with significant difference.

Apple is the most common crop cultivated in Resen region, Republic of Macedonia. In this region, apple powdery mildew caused by Podosphaera leucotricha (Ellis & Everh.) E. S. Salmon, and apple scab (caused by Venturia inaequalis (Cooke) G. Wint) are important pests in apple production. Trifloxystrobin is fungicide which acts against these pests and improves the yield of agricultural crops. We analyzed the presence of trifloxystrobin in two varieties of apples: Golden Delicious and Idaret from two different locations: Evla and Kriveni in Resen region, Macedonia. Fungicide was analyzed in four apple development phases, or from apple of the size a hazelnut, to the phase of harvest. Trifloxystrobin is analyzed by liquid chromatography-tandem mass spectrometry (LC-MS / MS) followed by an extraction/separation treatment with acetonitrile and the dispersive SPE - QuEChERS - method. Obtained values are compared with the maximum residues levels (MRL) according to the legislation of the Republic of Macedonia. We made a statistical processing of the data with Student's t-test. The analysis revealed that trifloxystrobin is present in Golden Delicious on both locations with a concentration within the range of 0.04 to 0.14 mg/kg, but mainly on Kriveni location. In the Idaret from Kriveni, it is detected only in early phase of apple maturing, while in Evla there is none or is below the detection limit. The value of t-test for Golden Delicious and Idaret from both locations are 1,946173039 and 1. They are lower than the critical t-value. That means that there is a significant difference in the presence of trifloxystrobin in apples from Kriveni and Evla. After comparing the obtained values with the MRL it can be concluded that apples from the two locations are safe for consumption. Key words: Trifloxystrobin, Fungicides, Apples, Golden Delicious, Idaret.

The aim of this research is to determine the presence of chlorpyrifos in two varieties of apples: Golden Delicious and Idaret on two different locations (Evla and Krveni) from Resen region in the country. Chlorpyrifos is organophosphate pesticide (insecticide) used to protect apples from insects which can cause significant damage in apple production. The apples are analyzed in four development phases and in each phase the presence of chlorpyrifos is determined. Chlorpiryfos analysis of the apples is performed by liquid chromatography-tandem mass spectrometry (LC-MS/MS) followed by an extraction/separation cleansing with acetonitrile and the dispersive SPE - QuEChERS - method. The results are compared with the maximum residue levels (MRL) prescribed by the legislation of the Republic of Macedonia. The conclusion is that chlorpyrifos is variously represented in most phases, regardless of the phase and location where apple is grown. At certain phase the concentration exceedes MRL, however during the harvest, apples are safe to be consumed. Higher presence of chlorpyrifos is found in Idaret apples at Kriveni location compared to Evla. Тhe presence of chlorpyrifos in Golden Delicious is almost equally in both locations. From the statistical analysis of the data it is noticeable that the use of chlorpyrifos doesn't depends on the (type) variety of apple but rater of the location where the apple is grown. Keywords: chlorpyrifos, pesticides, apples, Golden Delicious, Idaret