The Colorado potato beetle, Leptinotarsa decemlineata (Say), is a serious, widely distributed pest of potato and other crops. This pest is able to defoliate the host plant and cause severe yield loss. Moreover, the pest quickly becomes resistant to many chemical pesticides. Therefore, the development of novel biopesticides targeting this pest is urgently needed. The purpose of this study was to obtain new strains of the entomopathogenic fungus Beauveria bassiana and assess their efficacy against L. decemlineata adults under laboratory conditions. Twelve strains were isolated from cadavers of Colorado potato beetles collected in potato fields in the Czech Republic. Test beetles were treated by suspensions of conidia at the concentration of 1 × 10⁷ spores per milliliter and their survival was recorded daily for three weeks. The results of the bioassays revealed that all new native strains were pathogenic to L. decemlineata adults and caused mortality up to 100% at the end of the trial period with an LT₅₀ of about 7 days. These strains were more virulent than a reference strain GHA and some of them can be recommended for the development of a new mycoinsecticide against L. decemlineata. Our findings also highlight the importance of searching for perspective strains of entomopathogenic fungi among naturally infected hosts.

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Objective: The aim of the study was to evaluate the influence of gene polymorphisms and nongenetic factors on the somatic cell score (SCS) in the milk of Holstein (n = 148) and Simmental (n = 73) cows and their crosses (n = 6).Methods: The SCS was calculated by the formula SCS = log2(SCC/100,000)+3, where SCC is the somatic cell count. Polymorphisms in the casein alpha S1 (CSN1S1), beta-casein (CSN2), kappa-casein (CSN3), beta-lactoglobulin (LGB), acyl-CoA diacylglycerol transferase 1 (DGAT1), leptin (LEP), fatty acid synthase (FASN), stearoyl CoA desaturase 1 (SCD1), and 1-acylglycerol-3-phosphate O-acyltransferase 6 (AGPAT6) genes were genotyped, and association analysis to the SCS in the cow’s milk was performed. Further, the impact of breed, farm, year, month of the year, lactation stage and parity on the SCS were analysed. Phenotype correlations among SCS and milk constituents were computed by Pearson correlation coefficients.Results: Only CSN2 genotypes A1/A2 were found to have significant association with the SCS (p<0.05), and alleles of CSN1S1 and DGAT1 genes (p<0.05). Other polymorphisms were not found to be significant. SCS had significant association with the combined effect of farm and year, lactation stage and month of the year. Lactation parity and breed had not significant association with SCS. The phenotypic correlation of SCS to lactose content was negative and significant, while the correlation to protein content was positive and significant. The correlations of SCS to fat, casein, nonfat solids, urea, citric acid, acetone and ketones contents were very low and not significant.Conclusion: Only CSN2 genotypes, CSN1S1 and DGAT1 alleles did show an obvious association to the SCS. The results confirmed the importance of general quality management of farms on the microbial milk quality, and effects of lactation stage and month of the year. The lactose content in milk reflects the health status of the udder.

We evaluated the influence of CSN1S1 and LALBA polymorphisms on cow’s milk yield and quality. The analysis was done on Czech Simmental and Holstein cows. Non-genetic factors were included as well. CSN1S1 did not influence the milk performance in the first lactation. In the second lactation, cows with the BB genotype had significantly higher milk, protein, and fat yields than BC. The differences between LALBA genotypes were non-significant in the first lactation, while in the second lactation, the fat percentage was significantly higher in BB than in AB. The farm significantly influenced milk, protein, and fat yields in both the first and second lactations and fat percentage in the first lactation. The effect of CSN1S1 and LALBA genotypes on the milk technological quality was non-significant. Breed did not influence any of the evaluated technological traits and SCS. The ethanol test was not influenced by farm, season, lactation phase, protein percentage, breed, or non-fat solids percentage. Farm, season, and protein percentage significantly influenced milk fermentation ability, renneting, and SCS. The lactose content is a good indicator of udder health.

Low-temperature plasma (LTP) is currently one of the non-invasive and environmentally friendly methods of seed treatment and is massively tested on various types of crops. For the needs of gene banks, the use of LTP technology represents the treatment of seeds before sowing to improve the germination and emergence of long-term stored seed samples. Seeds of four genotypes of wheat, oats, flax, and rapeseed stored in the gene bank for 1, 10, and 20 years were plasma treated for 20, 25, and 30 min. Standard germination parameters (SG3, SG7, GR, MGT, and GI), as well as predictive models, were used to evaluate the effect of plasma treatment on seeds, and the effect on seed metabolism was assessed by superoxide dismutase (SOD) activity. The plasma treatment had different effects on germination and on the enzymatic activity of the tested species, and the result was influenced by both the duration of the treatment and the crop species/genotype. The plasma treatment has a positive effect on germination parameters in flax and rapeseed; in some variants, as in wheat, oats generally reacted negatively. SOD activity was variable in wheat, while higher activity with increasing treatment time was found in other crops. The results of this first study focused on long-term stored seeds and showed the potential of plasma treatment of seeds of plant genetic resources, the possibility of stimulating the germination of stored PGRs, and the need to optimize treatment conditions for individual genotypes.

The promising field of low-temperature plasma treatment, known for its non-invasive and environmentally sustainable nature, is being actively investigated for its ability to enhance germination, emergence, yield, and overall plant development in a broad spectrum of crops. For gene bank requirements, low-temperature plasma technologies can also improve germination parameters and promote the development seeds suitable for long-term storage. Seeds from four selected cultivars of wheat, oats, flax, and rapeseed stored in the gene bank for 1, 10, and 20 years were subjected to plasma treatments for 20, 25, and 30 min. The study evaluated the mean root and shoot length, root–shoot ratio, and seedling vigour index. Additionally, the malondialdehyde level, total polyphenol content, total flavonoid content, and total antioxidant capacity were analysed. Plasma treatment displayed varying effects on the morphological characteristics and antioxidant activity of the tested cultivars, which were influenced by treatment duration and cultivar. A positive effect of plasma treatment on seedling length, seedling vigour index, and root–shoot ratio was observed in flax cultivar ‘N-9/62/K3/B’ in all periods and in variants T2 and T3. Conversely, the wheat cultivar ‘Granny’ showed variable results, and the oat cultivar ‘Risto’ showed variable negative results in regards to mean root length and mean shoot length after plasma treatment. The indicators of oxidative stress and antioxidant capacity were affected in all the cultivars studied. A positive effect of plasma treatment on these indicators was observed in the wheat cultivar ‘Granny’, while flax cultivar ‘N-9/62/K3/B’ exhibited inconsistent results. While in cereals, a decrease in malondialdehyde content after plasma treatment was associated with an increase in polyphenol and flavonoid content as the treatment duration increased, small-seeded species responded somewhat differently. The rapeseed cultivar ‘Skrivenskij’ and flax cultivar ‘N-9/62/K3/B’ showed an increase in polyphenol and flavonoid content following a decrease in malondialdehyde levels. This study highlights the potential of low-temperature plasma treatment for long-term-stored seeds and its applicability to plant genetic resources. The findings emphasize the need for the further optimization of low-temperature plasma treatment conditions for different plant species and cultivars.