Semiochemical-based alternatives to synthetic toxicant insecticides for pollen beetle management

There is an urgent need to develop sustainable pest management systems to protect arable crops in order to replace the current over-reliance on synthetic insecticides. Semiochemicals are insect- or plant-derived chemicals that are used by organisms as information signals. Integrated pest management tools are currently in development that utilise semiochemicals to manipulate the behaviour of pest insects and their natural enemies to provide effective control of pests within the crop. These innovative tools usually require fewer inputs and can involve multiple elements therefore reducing the likelihood of resistance developing compared with use of synthetic toxicants. We review here the life cycle of the pollen beetle Brassicogethes aeneus (previously known as Meligethes aeneus) which is a pest insect of oilseed rape (Brassica napus) and describe the current knowledge of any behaviour mediated by semiochemicals in this species. We discuss the behavioural processes where semiochemical-based control approaches may be appropriate and consider how these approaches could be integrated into an integrated pest management strategy for this important arable crop

Root-emitted volatile organic compounds: can they mediate belowground plant-plant interactions?

peer reviewedBackground Aboveground, plants release volatile organic compounds (VOCs) that act as chemical signals between neighbouring plants. It is now well documented that VOCs emitted by the roots in the plant rhizosphere also play important ecological roles in the soil ecosystem, notably in plant defence because they are involved in interactions between plants, phytophagous pests and organisms of the third trophic level. The roles played by root-emitted VOCs in between- and within-plant signalling, however, are still poorly documented in the scientific literature. Scope Given that (1) plants release volatile cues mediating plant-plant interactions aboveground, (2) roots can detect the chemical signals originating from their neighbours, and (3) roots release VOCs involved in biotic interactions belowground, the aim of this paper is to discuss the roles of VOCs in between- and within-plant signalling belowground. We also highlight the technical challenges associated with the analysis of root-emitted VOCs and the design of experiments targeting volatile-mediated root-root interactions. Conclusions We conclude that root-root interactions mediated by volatile cues deserve more research attention and that both the analytical tools and methods developed to study the ecological roles played by VOCs in interplant signalling aboveground can be adapted to focus on the roles played by root-emitted VOCs in between- and within-plant signalling

Macrozoobenthos of the coastal zone in the region of Slowinski National Park

The present qualitative and quantitative study on macrozoobenthos was conducted in 1998 in the coastal zone of the Baltic Sea adjacent to the Słowinski National Park (SNP). The macrozoobenthos of this zone exhibited quantitative scarcity (12 species) and low content of the wet mass. More frequent were only Oligochaeta, Pygospio elegans, and Batyporeia pilosa. Because of a better specific diversity, density, and wet mass of the macrozoobenthos in the zone outside 1 nautical mile limit, the author suggests widening the proposed marine protected zone of the SNP giving it the status of marine Landscape Park up to 3 nautical miles

An attempt to rear rainbow trout (Salmo gairdneri Rich., 1863) in a temperature controlled tank

Rainbow trout were kept for 1 year in a tank of 2.5 m3 capacity, protected from overheating in summer and heated in winter. No water change was applied during the culture period. The fishes cultured showed good weight increments: the average weight of an 18-month old specimen was 193.3 g

Organizmy poroślowe (perifiton) zasiedlające trzcinę Phragmites australis i sztuczne podłoże w przymorskim jeziorze Kopań

Periphytic organisms inhabiting biotic and artificial substrates in Polish lagoons, locally known as „coastal lakes” are little known. In the frames of an interdisciplinary studies on the revitalisation of eutrophicated Lake Kopan, a study on different ecological formations, including the periphyton formations inhabiting Phragmites australis (CAV.) TRIN. ex STEUD. and artificial stilon (Polish trade name of a nylon) substrates, was carried out in 1999. It was demonstrated, that the average concentration of periphytic algae on reed in Lake Kopan amounted to 104 000 cells m⁻², periphytic microfauna - 54 874 specimens m⁻²; and macrofauna - 1 598 specimens m⁻². The concentration of periphyton on the studied biotic substrate was considerably lower compared to the organisms growing on the artificial substrate (potato-bag fabric, stilon fabric, foil), which were placed in Lake Kopan. The periphytic formation will play a significant role in the revitalisation project of the lake, by purification and deeutrophication of the waters, and in creating an additional, abundant food base for extensive culture of the rainbow trout.Organizmy poroślowe zasiedlajace biotyczne i sztuczne podłoża w polskich jeziorach przymorskich są słabo poznane. W ramach interdyscyplinarnych badań nad rewitalizacją zeutrofizowanego jeziora Kopan przeprowadzono w 1999 roku badania różnych formacji ekologicznych w tym formacji perifitonu zasiedlajacego Phragmites australis oraz sztuczne stylonowe podłoża. Wykazano, że średnie zagęszczenie glonów poroślowych na trzcinie w jeziorze Kopan wynosiło: 104 000. komórek m⁻², mikrofauny poroślowej 54 874 osobn. m⁻² oraz makrofauny 1 598 osobn. m⁻². Zagęszczenie perifitonu na badanym podłożu biotycznym było znacząco niższe w porównaniu do porośli na sztucznym podłożu (roszla, tkanina stylonowa, folia) umieszczonych w jeziorze Kopan. W projekcie rewitalizacji jeziora formacja poroślowa będzie spełniać istotną rolę w doczyszczaniu, deeutrofizacji wód oraz tworzeniu dodatkowej obfitej bazy pokarmowej dla ekstensywnej hodowli pstrąga tęczowego