Heavy metals accumulation in crops and soils poses a significant threat to the human health. A study was carried out in 2016 in order to assess hemp (Cannabis sativa L.) ability to accumulate heavy ...metals and to reveal its possibility as a phytoaccumulator or phytostabilizer. Two soil types from Croatia were used in experimental pots: Gleysoils (alkaline soil) and Stagnic Luvisol (acid soil). Majority of the varieties accumulated more heavy metals in roots than in above-ground biomass. Removal of Cd, Ni, Pb, Hg, Co, Mo and As was higher in acid soil. Potential ability for phytostabilization was observed in alkaline soil in order Cu > Cr > Cd > Mo > Hg > Zn > Ni > Co > As > Pb, while for acid soil in order Zn > Cd > Cr > Ni > Hg > Cu > Mo > As > Co > Pb. Some varieties exhibited a translocation coefficient (TC) more than 1 and shown the ability of hyper-accumulation for Zn, Hg, Mo and Cd. Higher accumulation of heavy metals in some varieties could lead to their general application for phytoaccumulation of heavy metals from polluted soils.
This study investigated the effects of essential oils thymol, eugenol, and 1,8-cineol for the prevention of losses caused by gray mold (Botrytis cinerea Persoon) in grapevine (Vitis vinifera Linne, ...cv. Karaerik) under in vitro and in vivo conditions. B. cinerea isolated from diseased grapevines was identified by 18S rRNA gene sequence analysis. The effects of 2.5, 5, and 10 microL doses of essential oils (EO) on mycelial growth, germ tube elongation, and spore germination were investigated in vitro, and the lesion formation on the leaves was examined in vivo. Compared to the control, both thymol and eugenol suppressed mycelial growth, depending on the dose increase, and caused 100% inhibition at the 10 microL dose, whereas 1,8-cineole had no effect on the same parameter at either dose. Germ tube elongation was 100% inhibited by 5 and 10 microL doses of thymol and eugenol, while the same doses of 1,8-cineole inhibited it by 49% and 85%, respectively. Conidiospore germination was inhibited by 22, 45, and 72% at 2.5, 5, and 10 microL doses of thymol, respectively. Under in vivo conditions, the three EOs inhibited lesion formation on leaves, depending on the concentration increase, and inhibition ended with 100% at their 100 microL dose. In addition, thymol was found to be the most effective EO under in vivo conditions. Our results show that these EOs, which are of biological origin and non-toxic to environmental health, have the potential to be used in the control of gray mold. Keywords: antifungal effect, biocontrol, essential oil, gray mold
Metabolic activity and structure of microbial communities are important indicators for soil health and fertility. BIOLOG's Ecoplate patented technology provides a method for estimating soil microbial ...community structure based on different substrate utilization. The optical density (OD) in the wells changed during the plate incubation due to the reduction of the tetrazolium dye and the OD values are used for the calculation of different indexes as parameters for microbial activity and community structure. The Gini coefficient, which was originally employed by economists for the estimation of wealth and income, has applications in a variety of biological studies. The Gini coefficient, alone or in combination with other indexes, can be used for the assessment of microbial diversity and species evenness. The aim of the current study was to calculate the Gini coefficient at several consecutive time points during the EcoPlate incubation, to make a graphical presentation through the corresponding Lorenz curves and to estimate the effect of applied biofertilizer on the soil microbial diversity. The results showed that the Gini coefficient decreased with the EcoPlate incubation and in case of a small difference between estimated coefficients, the graph was not very representative. The clear visual distinction between the corresponding Lorenz curves was not achievable. The Gini coefficient can be a useful parameter for estimating microbial diversity with a proper choice of time point measurement. Additional computations, which involve other indexes, comparisons or correlation analysis between them, can increase the benefits of the Gini coefficient application in the EcoPlate technique.
The study aimed to determine the effect of different slope positions on selected chemical properties of Pseudogley in the vineyard. The study was conducted in Zagreb, central Croatia. A total of 15 ...top-soil samples (0-30 cm) were collected from a hilltop, backslope, and footslope and analysed for pH, hydrolytic acidity (Hy), soil organic carbon (SOC) content, P.sub.2O.sub.5, K.sub.2O, and potentially toxic elements (As, Cu, Ni, Pb, and Zn). A slight increase in mean pH value from the hilltop to the footslope and a decrease in Hy were observed, although differences were not statistically significant. The SOC content was low and uniform along the entire slope. A significantly higher concentration of P.sub.2O.sub.5 at the footslope compared to the hilltop was established (10.4 and 3.4 mg/100 g of soil, respectively). The K.sub.2O concentration at the footslope (29.7 mg/100 g of soil) was significantly higher than at the backslope (21.2 mg/100 g of soil). The Cu, Pb, and Zn concentrations were significantly affected by slope positions in terms of download accumulation. The studied soil was contaminated by As, Ni, and Zn at the hilltop and the footslope and partly at the backslope, according to the Ordinance on the Protection of Agricultural Land from Pollution. The Cu concentrations exceeded the maximum allowed concentrations only on the backslope and footslope. The minor differences in studied soil properties between slope positions can be attributed to a short length, low and uneven inclination, and relatively short-term anthropogenic influence.
The issue of storage and protection of yilded seeds from storage pests is fundamental to seed science, the nutrition of people and animals as well as the maintenance of state reserves. During ...2019-2021, in the experimental field of IASS "Obraztsov chiflik"- Rousse, in a long-term stationary fertilizer experiment, seeds of common bean variety Obraztsov chiflik 12 were obtained utilizing the following fertilization options: 1- individual nitrogen fertilization; 2-individual phosphorus fertilization; 3- individual potassium fertilization; 4- combined NP application; 5- combined NK application; 6- combined PK application; 7- triple combination of NPK. An unfertilized control variant was maintained for comparison purposes. The study aims to entomologically evaluate seeds regarding damage by bean weevils after crop harvesting. Measurements of yield, 1000-seed weight, damaged seeds percentage, Index of infestation, as well as weight loss were taken. The combined application of NP demonstrated the greatest positive effect on the yield qualities of beans, however it lead to an intermediate position of the yield in terms of damage by bean weevil. The variant treated with combined NK fertilization resulted in the lowest percentage of damaged seeds and Index of infestation; it was followed by the variant with full mineral fertilization and the control variant. The individual application of N resulted in highest damaged seeds percentage as well as highest Index of infestation; it also ensured the highest weight loss on average for the studied period.
PDF