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  • Author: Aleksandra Kowalczyk x
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Abstract

This work presents the results of an analysis of concentration levels of selected trace metals (Pb, Zn, Cu, Cd) in plants and soil near the main roads of the Warsaw agglomeration. The aim of the study was to assess the degree of contamination by selected trace elements of plants growing at different distances from the road (directly at the roadside and 50 meters away from the road) and to examine the relationship between the concentration of the tested parameters in the soil and their content in the plant. It was found that the lack of clear differentiation in the levels of all heavy metals in plants depending on the distance from the road was associated with the possibility of considerable pollutant migration. In addition, it was found that dandelion usually reveals higher concentrations of heavy metals than meadow-grass.

Abstract

Sclerotinia sclerotiorum (Lib.) de Bary is considered as one of the most harmful soilborne pathogens, which reduces productivity of horticultural crops. Currently used chemical or biological methods for the eradication of S. sclerotiorum from a soil are not very effective. The aim of this study was to evaluate the possibility of eradication of S. sclerotiorum sclerotia from a soil using the Trichoderma isolates, which were multiplied on the organic carriers prepared from agro-industrial wastes and by-products: WsA (wheat straw + apple pomaces), WsP (wheat straw + potato pulp) and T-GRAN (dry onion rind, apples and strawberry pomaces, rapeseed meal). The results showed that soil amendment with organic materials overgrown with the Trichoderma fungi had a significant reducing effect on S. sclerotiorum. Especially effective was the carrier WsA overgrown with T. virens TRS114, which completely prevented the survival of sclerotia of S. sclerotiorum regardless of the dose of application. Less effective was the WsP carrier. However, addition WsP overgrown with T. atroviride TRS40 at the 5% w/v, resulted in survival only 6.7% of sclerotia. In the greenhouse experiments with lettuce, the application of granulates T-GRAN into the soil had different impact on S. sclerotiorum depending on the conditions to the pathogen development. In conducive conditions, an addition of the organic substances without Trichoderma significantly decreased the yield of lettuce plants. A positive effect on the growth of plants was observed after the application of T-GRAN overgrown with Trichoderma.

Abstract

Canine parvovirus type 2 is one of the most common causes of death among puppies. Despite preventive vaccination, the disease continues to be diagnosed. The aim of the study was to provide a molecular characterization of CPV-2 isolates found in southeastern Poland. Genetic CPV-2 material was isolated from the blood (n=10) and feces (n=50) of infected dogs. The presence of CPV-2 was confirmed by amplification of sequences coding both VP1 and VP2 protein. The products of the PCR reaction with primers amplifying VP2 protein were sequenced and used for genotyping. Bioinformatics analysis of the sequenced PCR product was performed to determine the phylogenetic relationships with variants recorded in the public databases. Based on the analysis of polymorphism in the nucleotide sequence 7 nucleotide variants were detected and assigned into four amino acid groups. Representatives of three groups contained asparagine at amino acid position 426 of the VP2 protein, which is characteristic of CPV-2a. The variant from the fourth group belonged to type CPV-2b. CPV-2a is the dominant antigenic type of CPV-2 in Poland. The pathogen’s high degree of polymorphism is manifested not only by the presence of numerous variants within the type, but also by the presence of representatives of type CPV-2b. Further studies of the molecular epidemiology of CPV-2 are necessary to optimize the effectiveness of preventive measures.