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We review aspects of invertebrate biodiversity relevant to the management of Scots pine forests. At a landscape level, the area occupied by the host tree species, the length of time that species has been present, and the taxonomic relatedness of the host to other trees, all influence invertebrate biodiversity. At a stand level, tree size and above-ground architecture affect the number of niches available. Consideration needs to be given to the various feeding guilds since they exploit different components of these niches. Although there have been few published studies of invertebrate numbers in relation to niche availability in Scots pine, it would appear that the deadwood habitat is underrepresented in Scots pine forests and increasing the availability of this niche would enhance invertebrate biodiversity. An issue for managers is the need to distinguish between increasing total biodiversity and the encouragement of rare species with particular niche requirements which may also be dependent upon the continuity of that niche within a landscape. Se revisan distintos aspectos de la biodiversidad de invertebrados relevantes en la gestión de los bosques de Pino silvestre. A un nivel de paisaje, el área ocupada por la especie del árbol anfitrión, el tiempo que la especie ha estado presente, y la relación taxonómica del anfitrión con los otros árboles, influyen en la biodiversidad invertebrada. A un nivel de rodal, el tamaño del árbol y la arquitectura aérea afectan el número de nichos disponibles. Debe prestarse atención a los diversos grupos alimenticios de invertebrados, puesto que ellos explotan diferentes componentes de esos nichos. Aunque ha habido pocos estudios publicados sobre el número de invertebrados en relación con la disponibilidad del nicho en Pino silvestre, parece que el hábitat de la madera muerta está infrarrepresentada en los bosques de Pino silvestre y que el aumento de la disponibilidad de este nicho mejoraría la diversidad biológica de invertebrados. Un aspecto para los gestores es la necesidad de distinguir entre el aumento de la biodiversidad total y favorecer las especies raras con requisitos particulares del nicho que también pueden depender de la continuidad de ese nicho dentro de un paisaje.

We review aspects of invertebrate biodiversity relevant to the management of Scots pine forests. At a landscape level, the area occupied by the host tree species, the length of time that species has been present, and the taxonomic relatedness of the host to other trees, all influence invertebrate biodiversity. At a stand level, tree size and above-ground architecture affect the number of niches available. Consideration needs to be given to the various feeding guilds since they exploit different components of these niches. Although there have been few published studies of invertebrate numbers in relation to niche availability in Scots pine, it would appear that the deadwood habitat is underrepresented in Scots pine forests and increasing the availability of this niche would enhance invertebrate biodiversity. An issue for managers is the need to distinguish between increasing total biodiversity and the encouragement of rare species with particular niche requirements which may also be dependent upon the continuity of that niche within a landscape., Se revisan distintos aspectos de la biodiversidad de invertebrados relevantes en la gestión de los bosques de Pino silvestre. A un nivel de paisaje, el área ocupada por la especie del árbol anfitrión, el tiempo que la especie ha estado presente, y la relación taxonómica del anfitrión con los otros árboles, influyen en la biodiversidad invertebrada. A un nivel de rodal, el tamaño del árbol y la arquitectura aérea afectan el número de nichos disponibles. Debe prestarse atención a los diversos grupos alimenticios de invertebrados, puesto que ellos explotan diferentes componentes de esos nichos. Aunque ha habido pocos estudios publicados sobre el número de invertebrados en relación con la disponibilidad del nicho en Pino silvestre, parece que el hábitat de la madera muerta está infrarrepresentada en los bosques de Pino silvestre y que el aumento de la disponibilidad de este nicho mejoraría la diversidad biológica de invertebrados. Un aspecto para los gestores es la necesidad de distinguir entre el aumento de la biodiversidad total y favorecer las especies raras con requisitos particulares del nicho que también pueden depender de la continuidad de ese nicho dentro de un paisaje.

The role of biotic mechanisms in baculovirus (BV) dispersal was investigated using three Lepidopteran pests; Plodia interpunctella (Hubner), Ephestia cautella Walker and Mamestra brassicae L. and their respective BVs. The first two, pyralid moths, are pests of stored products, and the third is a pest of brassicas. Detailed host biology and virus mortality studies were undertaken to provide background information for the main investigation of virus dispersal using P.interpunctella. BV infectionincreased larval activity and thus BV dispersal in all three species until the disease at an advanced stage caused sluggish behaviour and mortality. However, larva to larva virus transmission was limited, especially as the integuments of diseased pylarids did not rupture and cannibalism was rare when a suitable food supply was available. P.interpunctella adults which received a sub-lethal BV dose in the larval stages appeared normal but the proportion of eggs oviposited, the viability of the eggs and the survival of the progeny were reduced. However, no BV was detected in the adult stage. Transovum transmission occurred if the adults were externally contaminated with BV. Scavangers, predators and adult parasitoids which fed on diseased prey voided viable BV in their faeces. This contaminated the larval medium and resulted in larval infection. The predators tested readily fed on diseased prey but the parasitoids were less able to compete with BV for hosts, Bracon hebetor Say preferentially avoided diseased hosts. There was little evidence to indicate that BV can be mechanically vectored between host larvae on the ovipositor of a parasitoid or the mouthparts of a predator. The relative potential of the host and other biotic mechanisms to cause BV dispersal is discussed.