Monitoring of nitrate (NO(3)(-)) and nitrite (NO(2)(-)) content in agricultural products in Slovenia has been carried out since 1996. The results of monitoring over the period 1996-2002 are presented. During this time 924 samples of 14 different agricultural products (potato, lettuce, apples, carrot, silage maize, cabbage, grapes, peaches, string beans, cereals, pears, cucumbers, strawberries and tomato) were analysed. The samples were taken at the time of maturity directly from growing sites and they were analysed using segmented flow analysis. The average nitrate contents were the highest in lettuce (1,074 mg kg(-1)), cabbage (881 mg kg(-1)), string beans (298 mg kg(-1)) and carrot (264 mg kg(-1)), and they were moderately high in potato (158 mg kg(-1)), silage maize (122 mg kg(-1)), strawberries (94 mg kg(-1)), cucumbers (93 mg kg(-1)) and cereals (49 mg kg(-1)). Low nitrate contents (below 6 mg kg(-1)) were found in fruit (grapes, peaches, apples and pears) and tomato. With the exception of cereals (8.9 mg kg(-1)), apples (1.5 mg kg(-1)), potato (1.2 mg kg(-1)) and pears (1.0 mg kg(-1)) the content of nitrites did not exceed 0.5 mg kg(-1). It may be concluded that the results of the monitoring were in most cases similar to the results of investigations obtained in other countries.

<p style="text-align: justify;"><strong>Aim</strong>: To investigate the effect of reducing leaf area by shoot hedging in combination with bunch thinning on metabolite concentration and sensorial quality of Sauvignon blanc grapes and wines.</p><p style="text-align: justify;"><strong>Methods and results</strong>: Four vine treatments were conducted: shoot hedging/bunch thinning (SH/BT), shoot hedging/no bunch thinning (SH/NBT), full canopy/bunch thinning (FC/BT) and full canopy/no bunch thinning (FC/NBT). Shoot hedging delayed total soluble solids accumulation at the beginning of the grape maturation in SH/BT and SH/NBT treatments. At harvest there were no significant differences in the concentration of hydroxycinnamoyl tartaric acids, glutathione, total soluble solids, titratable acidity and pH value in grape juice between all treatments and methoxypyrazines were below the limit of detection. Lutein concentration in grape berry was higher in treatments without bunch thinning, while there was no significant difference in the concentration of β-carotene and neoxanthin. The highest leaf area to yield ratio (FC/BT) resulted in higher concentration of glutathione in must and higher concentration of thiols in Sauvignon blanc wines. Upon sensory evaluation, the FC/BT wine was best scored for overall quality and heavier tropical aroma, whereas the FC/NBT wine was best scored for fresh tropical aroma and second best for overall quality.</p><p style="text-align: justify;"><strong>Conclusion</strong>: Leaf area to yield ratio impacted berry ripening kinetics, grape and wine metabolite composition, and sensorial properties of Sauvignon blanc wine.</p><p style="text-align: justify;"><strong>Significance and impact of the study</strong>: The study showed that the highest leaf area to yield ratio resulted in the best overall sensorial quality of wine.</p>

Nitrate (NO3 -) and nitrite (NO2 -) levels of a total 1195 samples of nine different vegetables (lettuce, potato, cabbage, carrot, string beans, tomato, cucumber, cauliflower and pepper) collected at several locations of an intensive agricultural area in Slovenia were analysed during a period of 13 years. The content of NO2 -and NO3 -ions in commercial mature samples was determined using a segmented flow analyser. The average NO3 -content was the highest in lettuce (962 mg/kg), cabbage (795 mg/kg), string beans (298 mg/kg), carrot (264 mg/kg), cauliflower (231 mg/kg), potato (169 mg/kg) and was moderately high in cucumber (93 mg/kg) and pepper (69 mg/kg). A low NO3 -content was found in tomato (<10 mg/kg). The average values of NO2 -did not exceed 0.5 mg/kg, with the exception of potato (1.08 mg/kg). Six samples of lettuce exceeded the maximum permissible level of NO3 -according to current European Union (EU) legislation. Based on the results of our investigation, we assessed the approximate daily intake (DI) of NO3 -and NO2 -to human body. The results indicated that with the consumption of potato, the daily intake per inhabitant is close to the acceptable DI permitted in EU.

Honey bee colonies were exposed to pesticides used in agriculture or within bee hives by beekeepers: coumaphos; diazinon; amitraz or fluvalinate. Samples of bee workers, larvae and royal jelly were analysed using Gas Chromatography-Electron Capture Detection (GC-ECD). Amitraz was quantified using High Performance Liquid Chromatography (HPLC), and Gas Chromatography-Tandem Mass Spectrometry (GC/MS/MS) was used for quantification of diazinon. Sixth day after treatment, coumaphos was found in the royal jelly (250 ng/g) secreted by nurse workers and fluvalinate was found in both bee heads (105 ng/g, 8 days after treatment) and in larvae (110 ng/g, 4 days after treatment). Amitraz residues in all sampled material were below the level of detection of 10 ng/g. Diazinon was not detected in any of the analysed samples. The large quantities of fluvalinate found in bee heads and larvae, the coumaphos residues in royal jelly, and additional potential sub-lethal effects on individual honey bees or brood are discussed.

Apples, lettuce and potatoes (404 samples) produced in the Republic of Slovenia were analysed for pesticide residues at the Agricultural Institute of Slovenia, Ljubljana, in 2001-04. Sampling from eight agricultural production areas was performed at market producers at the harvesting of products or in storehouses after the pre-harvest interval of plant protection products used. Samples exceeding the maximum residue levels were the following: three apple samples (2.0%) containing 0.33-2.24 mg kg(-1) (phosalone and tolylfluanid), three lettuce samples (3.1%) containing 0.14-6.36 mg kg(-1) (dimethoate, dithiocarbamates and metalaxyl) and 36 potato samples (23.1%) containing 0.06-0.51 mg kg(-1) (dithiocarbamates). Residues of two or more active substances were found in 73 apple samples (48.3%), of which the maximum residue limit (MRL) was exceeded by three samples (2.0%) with the values ranging from 0.33 to 2.24 mg kg(-1), and nine lettuce samples (9.3%), for which the MRL was exceeded by three samples (3.1%) with values from 0.14 to 6.36 mg kg(-1). In potato samples, only residues of dithiocarbamates or no residues at all were found. Residues of the dithiocarbamate group were the most frequently found, i.e. in 66 apple samples (43.7%), 30 lettuce samples (30.9%) and 38 potato samples (24.4%).