Elevation gradient affects the distribution and host utilisation of Zatypota anomala (Hymenoptera, Ichneumonidae) associated with mesh web weaving spiders (Araneae, Dictynidae)

The spatial distribution of parasitoids is closely linked to the distribution and ecological requirements of their hosts. Several studies have documented changes in the fauna composition of parasitoids in response to elevation, but data on parasitoids associated with spiders are missing. The koinobiont ichneumonid wasp Zatypota anomala is strictly specialised on spiders of the genus Dictyna (Dictynidae) in Europe. We examined the distribution of spiders of the family Dictynidae in forest ecotones in central Europe across a broad elevation gradient (110–1466 m a.s.l.). We checked the spiders for parasitism by Z. anomala. It was most abundant at the mid-elevations (median 712 m a.s.l., range 179–870 m a.s.l.). We identified four dictynid spider species as Z. anomala hosts. These were Dictyna arundinacea, Dictyna uncinata, Nigma flavescens, and Nigma walckenaeri. All four species and the genus Nigma were recorded as hosts for the first time. The parasitoids strongly preferred juvenile instars of their hosts. The body length differed between parasitised Dictyna and Nigma spiders (medians: 1.95 mm and 2.55 mm, respectively). The distribution of Dictyna and Nigma spiders overlapped along the elevation gradient, but parasitism incidence significantly differed between spider genera along the elevation gradient. Nigma was parasitized at lower elevations between 179–254 m a.s.l. and Dictyna at higher elevations between 361–870 m a.s.l. The phenology of Z. anomala is closely tied to the univoltine life strategy of its host spiders. The parasitoid female oviposits in autumn, and its offspring overwinter as larvae on the host, reach adulthood during spring, and pass the summer as an adult

Spring Abundance, Migration Patterns and Damaging Period of <i>Aleyrodes proletella</i> in the Czech Republic

The cabbage whitefly has become an important pest on brassica vegetables in Central Europe. It does not destroy the affected plants, but the product becomes unmarketable, causing considerable economic losses. The pest is also difficult to control due to its way of life and because it develops resistance to some of the active components of insecticides. In organic farming systems, insecticides are strictly restricted, but neither predators nor whitefly parasitoids are able to keep the pest at a tolerable level. It is, therefore, necessary to become familiar with the whitefly’s life cycle and habits, including mass migration from winter hosts to vegetables. We inspected 44 rapeseed fields across the republic in the period 2014–2021 in order to find the connection between the presence of oilseed rape fields near vegetable growing areas (VGAs) and the abundance of the overwintering cabbage whiteflies. We also conducted regular weekly monitoring of whitefly occurrence in the main cultivation area of the Czech Republic (Polabí) with the aim of specifying critical data important for the successful control of this pest. We found that the cabbage whitefly incidences were many times higher in rapeseed fields close to VGAs compared to areas where the crops are not adjacent. The average number of whiteflies was 0.59 individuals per plant in VGA-1 (oilseed rape grown inside this area or up to 1 km far), 0.052 in VGA-2 (distance 3–10 km from vegetable fields) and 0.014 in VGA-3 (more than 20 km). In the extremely warm year 2016, the difference was up to sixty times. The first CW eggs laid on cruciferous vegetables were usually found around 20 May. The period of mass migration of CW adults to cruciferous vegetables was between 6 June and 2 August. At this time, vegetables are most vulnerable to damage. Successful control of the cabbage whitefly requires the use of fabric netting, combined with an insecticide as needed and trap plants as needed; the latter have to be destroyed before adult whiteflies hatch—typically in early July

Optimization of using of pesticides against pests in system of integrated production of vegetable

Methodology is addressed to farmers and growers of Brassica vegetable, mainly for growers in system of integrated production of vegetable. Methodology contain information and recommendation for control against main pests of Brassica vegetable necessary for implementation of principles of integrated control in agreement with legislation requirements valid from 2014. Selection of means against pests is based on evaluation of pre-harvest period of active substances of pesticides and evaluation of side effects of these substances on nontarget organisms. For each active substance of pesticide and evaluated vegetable species, data about residue degradation in dependence on time from term of application. According to residue degradation of pesticides in vegetable it is possible to state action pre-harvest periods for low-residue and no-residue vegetable production. Data about side effects on natural enemies and other non-target organisms are given for each active substance of pesticide allowed in EU for vegetable control including substances potentially available for allowing in the Czech Republic. According this knowledge it is possible to rank the active substance into green, yellow and red list of pesticides for integrated system of Brassica vegetable production

Interaktivní analýza systémové architektury: Případová studie nástroje IMiGEr

Diagramy softwarových systémů mohou být komplexní a mohou se snadno skládat ze stovek až tisíců komponent různých typů a jejich propojení. Porozumění jejich interním strukturám skrz odpovídající vizualizaci je tak nesnadný úkol. Speciálně pokud není možné utvářet hierarchické struktury. Mezi hlavní problémy patří vizuální šum a protichůdné požadavky zobrazení celého grafu a detailů zároveň. Pro řešení těchto problémů jsme v nástroji IMiGEr vytvořili metodu průzkumu grafů založenou na principu zobrazení detailů na požadavek. Umožňuje efektivní průzkum rozsáhlých diagramů s více typy uzlů. Tento článek ukazuje klíčové techniky a jejich kombinace umožňující demonstraci přínosů pro pochopení architektury.Software systems of all kinds tend to be complex, easily comprising hundreds of components of various types and many more interconnections. Understanding of their internal structure through appropriate visualization is, therefore, a challenging task, especially when hierarchical decomposition is not possible. Among the key hindrances in existing graph-based visualizations of such systems are visual clutter and the contradictory requirements of ideally seeing the whole system context while showing enough details to analyze particular elements. Addressing such issues to enable effective comprehension of large multi-modal graphs, we developer a method of their exploration leaning on user interaction with the diagram and details on demand principle, implemented in IMiGEr. In this paper, we show the key techniques it employs, explain their combination and illustrate the benefits on the representative tasks in software architecture understanding

The support of occurrence of beneficial organisms in the orchards:certified methodology

The publication is intended for the fruit growers and was worked upon the base of the results of the projects NAZV QJ1210209 a RO0416. It contains information about important beneficial organisms and possibilities of their support in orchards

Invasive pest species in fruit crops in the Czech Republic

The publication summarizes the basic information about invasive pest species in fruit orchards, spreading to our country since 2000. Information about morphology, similar species, area of origin, distribution in Europe and Czechia, risk of introduction, life cycle, host plants, methods of monitoring and control, are provided for each pest species

Minimization of risk of pesticide residues in fruit production:certified methodology

The publication is intended for fruit growers who are included in integrated fruit production systems. The information and the recommendations presented in the matarial can help them to minimize risk of residues of of of pesticides on non-target organisms, mainly natural enemies. In addition, the minimizing of pesticide impact on human health is considered. All recommendations are in the accordance with requirements of legislation which will be in force from 2014 for IPM and also for convention regimes of fruit protection. The spray scheduling is based on the knowledge of pesticide pre-harvest period coupled with the information about their side effects on non-target organisms. Environmental behaviour of pesticide residues from the application to the harvest is desribed for each active ingredient allowed in the Czech Republic in apples and pears. These data enable to assess the action pre-harvest periods for the both low-residual and non-residual fruit production. Information about side effect on natural enemies of pests and other non-target organisms have been worked up for each active substance of pesticides allowed in fruits in the Czech Republic. This knowledge allows us to classify pesticides into three groups marked as a so called green, yellow and red list for IPM growing systems. The possibilites of the use of biological and biotechnological methods are outlined at the end of the publication