Nikolett Czipa

Determination of essential and toxic elements in Hungarian honeys.

The aim of this present study was determination of essential and toxic element concentrations in 34 mono- and multi-floral honey samples from four geographical regions of Hungary, and examination of the connection between the floral origin and the element content. Ten elements (Al, Ca, Cu, Fe, K, Mg, Mn, P, S and Zn) were identified by ICP-OES and six (As, Cd, Cr, Mo, Pb, Se) were analysed by ICP-MS. Potassium, calcium, and phosphorus were the most abundant elements with mean concentrations of 372, 47.9 and 44.3 mg kg(-1), respectively. The essential element content was very low in the analysed samples and generally below literature values. The concentrations of toxic elements were sufficiently low as to pose no risk to human health. The concentrations of aluminium, arsenic, cadmium and lead were low, with mean concentrations of 1028, 15.6, 0.746 and 45.5 μg kg(-1), respectively. Three honey groups (acacia, rape and sunflower) were distinguished by linear discriminant analysis from their element content.

Examination of honeys and flowers as soil element indicators

Detection of soil element deficiencies is time consuming, requiring a major commitment for field work and analysis. Bees concentrate some elements in their honey which could allow soil element concentrations to be predicted without having to take large numbers of soil samples. We measured 14 element concentrations in soil, sunflower, acacia flower and honey samples from two different regions of Hungary. Across sites, the elements with significant correlation coefficients between honey and soil concentrations, in descending order of probability, were Cu > Ba >Sr = Ni > Zn > Mn = Pb >As. Bioconcentration from soil to honey was similar for areas with acacia and sunflower flowers. In the macroelements, it was the greatest for K, S and P and least for Mg and Na, and in the microelements, greatest for B, then Zn, then Cu, then As, Mo and Sr and least for Fe, Ba, Mn and Pb. It is concluded that in acacia and sunflower-growing regions, honey can give an accurate estimate of soil element concentrations for Cu and Ba and provides relevant information for Sr, Ni, Zn, Mn, Pb and As.

Macro-element ratios provide improved identification of the botanical origin of mono-floral honeys

Major macronutrient concentrations (K, Ca, Mg, Na, P, and S) and element ratios were determined in 140 Hungarian mono-floral honey samples (acacia, linden, sunflower, rape, chestnut, forest, silk grass, and facelia) by inductively coupled plasma-optical emission spectrometry (ICP-OES). One-way ANOVA (LSD and Dunnett T3 test) and linear discriminant analysis (LDA) were used to determine the botanical origin based on the element content and element ratio of different honey types. Analysing six element concentrations in the honeys of different botanical origin with LDA allowed the botanical origin of 96% of honeys to be predicted. Reducing the examined elements to K, Mg, and Na increased the accuracy of predictions, but it was still not possible to distinguish acacia and facelia honeys. However, examination of element ratios showed that K/Na and K/Mg ratios were able to separate every honey type from each other with 100% cross-validation. It is concluded that using macro-element ratios rather than macro-element concentrations, it is possible to precisely discriminate the floral origin of honey samples.

The effect of geographical origin on the composition of honey

One of the biggest challenges for the safe maize production is the yield stability in a wide range of environments with different soil fertility, weather conditions, prevailing pests and diseases as well as cultural practices. In order to achieve it, new hybrids with higher tolerance to biotic and abiotic stress are continuously being created. In order to compare performance of maize hybrids in environments with different levels and types of stress, and relate it to the stalk lodging incidence, we compared performance of 64 maize hybrids obtained by crossing 16 inbred lines with four inbred testers in three different environments. Two environments at same location (Rugvica) differed in crop rotation, and the third environment at location Botinec was considered as dry because of low water capacity of the soil. Mixed models that included all design elements and genetic background of hybrids were used to analyze the effect of lodging on yield in different environments. The results show that stalk lodging had a significant effect on yield, but significant lodging x environment interaction indicates that this effect was rather environment specific.Sweet pepper Istra F1 hybrid was grown in a greenhouse on K rich soil. For evaluation of K antagonism, two K rates (55 and 85 kg ha-1) were applied in a randomized complete block design with four replications. Total number of fruits, total number of BER affected fruits as well as average fruit mass were recorded for each harvest. Fruit and leaf K and Ca content were determined at three plant growth stages (at the stage of the first, third and fifth fruit cluster). Higher K rate gave higher : average fruit mass (169.45 g), total number of fruits per plant (7.95), number of BER affected fruits per plant (3.82), K in leaves (5.44% DM), K in fruits (6.35% DM), but negatively correlated with Ca concentration in fruits (0.57% DM) and leaves (3.24% DM). This resulted in decreased marketable yield of sweet pepper fruits.