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Beneficial species of predators and parasitoids play an important role in sustainable pest control. Toxicity evaluation of insecticides against the natural enemies of the pests is very important in the selection of a product intended for application within the Integrated Pest Management (IPM). The effectiveness of beneficial species as biological control agents may be compromised by side effects caused by insecticides. Tests were conducted under laboratory conditions to determine the toxicity of 18 insecticides against the beneficial species Encarsia formosa Gahan, Macrolophus pygmaeus Rambur and Amblyseius cucumeris Oudeman. Plant protection products Rapax (i.e. Bacillus thuringiensis subsp. kurstaki strain EG 2348) 0.1%, Dipel 2X (i.e. Bacillus thuringiensis var. kurstaki strain ABTS) 0.1%, Naturalis (i.e. Beauveria bassiana strain ATCC 74040) 0.1%–0.15%, Helicovex (i.e. Helicoverpa armigera nucleopolyhedro virus Hear NVP, DSMZ–BV0003) 0.02%, Neem Azal T/S (i.e. azadirachtin) 0.3% and Limocide (i.e. orange oil) 0.4% were slightly toxic (toxicity up to 37%) to the tested bioagents. They can be successfully applied in integrated plant protection systems. Toxic to highly toxic were the following insecticides: Koragen 20 SC 0.02%, Voliam Targo 063 SK 0.08%, Ampligo 150 ZK 0.04%, Closer 120 SC 0.04%, Confidor Energy OD 0.08%, Vaztak new 100 EC 0.03%. These insecticides should be avoided when introducing bioagents into greenhouses. [ABSTRACT FROM AUTHOR]

European coasts suffer notably from hazards caused by low-probability and high-impact hydrometeorological events. The aim of the study is to assess in probabilistic terms the magnitude of storm‐induced flooding hazard along Varna regional coast (Bulgaria, western Black Sea) and to identify susceptible coastal sectors (hotspots). The study is performed employing the Coastal Risk Assessment Framework (CRAF) developed within EU FP7 RISC-KIT project. It constitutes a screening process that allows estimation of relevant hazard intensities, extents and potential receptors’ exposure vulnerability within predefined sectors. Total water level was the chief property considered for calculation of coastal flooding hazard. It was estimated using Holman model (for sandy beaches) and EurOtop formulation (for artificial or rocky slopes). Resulting values were subjected to Extreme Value Analysis to establish that the best fitting distribution corresponds to Generalized Extreme Value distribution. Furthermore, hazard extents were modelled by means of bathtubbing or overwash estimation in order to form the flooding hazard indicator. Land use, social vulnerability, transport systems, utilities and business settings were considered as exposure indicators. Finally, potential risk was assessed by coastal indices following an index-based methodology, which combines hazard and exposure indicators into a single index, thereby providing base for comparison of coastal sectors’ vulnerability. The study found that the concentration of hotspots is highest in Varna Bay.

Samples were collected from the Plovdiv, Bulgaria. The aim of this study was to is to compare the similarity and remoteness of different irrigation regimes: 1. Irrigation regime (50% of irrigation rate) and 50% fertilization; 2. Irrigation regime (75% of irrigation rate) and 50% fertilization; 3. Optimal irrigation regime (M-100%) with 50% fertilization; for the variety Paneкra during the period 2016-2018 year and to identify the link among bioactive compounds of tomatoes through the mathematical model HJ-biplot. An important indicator of the quality of tomatoes is the content of total dyes. The highest values were found in tomato farmed irrigation regime (50% of irrigation rate) where total dyes attained up to 4.95 mg/100 g. The β-carotene content determines the orange color of the tomato fruit. The good combination of the two components (lycopene and β-carotene) with an antioxidant effect determines hybrids of tomatoes such as hybrids of high biological value. In the present study the content β-carotene ranges from 0.26 to 0.35 mg/100 g. The content of β-carotene is higher at a 50% of irrigation rate [ABSTRACT FROM AUTHOR]

The aim of the present research work was to evaluate the similarity and remoteness of the impact of different irrigation regimes for tomatoes (Vitelio variety) and their grouping by main biochemical indicators, using mathematical approaches (cluster analysis and factor analysis). Two-year data from a field experiment was used including a non-irrigation and an optimum option, as well as options for canceled irrigation and low irrigation norms (12 options in total). The experiment was carried out in Plovdiv in the period 2016-2017. Cluster analysis results were in line with the conclusions from the irrigation and fertilization regime analyses and their impact on the tomato quality indicators. The strongest positive correlation existed between the indicators common dyes and lycopene for both experimental years. There was a strong negative correlation between the indicators lycopene and beta-carotene. The basic indicators leading to the separation of the irrigation and fertilization options into clusters were the following quality indicators: titratable organic acids, ascorbic acid, common dyes, lycopene and betacarotene combined in the first factor, responsible for 78.621% of the total dispersion of the variables. [ABSTRACT FROM AUTHOR]