Epizootiology of a Nuclear Polyhedrosis Virus (Baculoviridae) in European Spruce Sawfly (Gilpinia hercyniae): Spread of Disease from Small Epicentres in Comparison with Spread of Baculovirus Diseases in Other Hosts

Within and between population variation in disease resistance in cyclic populations of western tent caterpillars: a test of the disease defence hypothesis

“…2000; Myers 2000; Van Frankenhuyzen et al . 2002; Cory & Myers 2003), and in some sawflies in the family Diprionidae (Entwistle et al . 1983; Moreau et al .…”

The compatibility of a nucleopolyhedrosis virus control with resistance management for Bacillus thuringiensis: Co-infection and cross-resistance studies with the diamondback moth, Plutella xylostella

“…NPV products are commercially available for heliothine pests in the US and Australia and have been successfully used globally in various agricultural and horticultural settings (Hunter-Fujita et al, 1998) and in the development of IPM in cotton (Mensah, 2002). While NPVs have limitations as insecticides, especially in their cost of production, they can, through the build-up of infectious particles and secondary cycles of infection in pest populations, be an eVective means of long-term population control (Reed and Springett, 1971;Entwistle et al, 1983;Dwyer and Elkinton, 1993;Fuxa and Richter, 1994;Young, 1998;Bonsall, 2004). This, in turn can lead to increased spray intervals and reduced costs for growers (Moscardi, 1999).…”

The impact of diseases and pathogens on insect population dynamics

“…For example, Spruce sawfly ( Gilpinia hercyniae ) is known to be a major pest in spruce plantations in both Canada and Wales. After the release of a nuclear polyhedrosis virus, disease epizootics (Entwistle et al ., 1983) in the susceptible sawfly population were observed, leading to massive mortality and the eventual reduction in sawfly numbers. In Canada, the abundance of sawfly is relatively low and endemic nuclear polyhedrosis virus can still be recovered from the pest insect populations.…”

“…The delays between disease transmission and the release of infectious particles known from insect–disease interactions and the decline of parasite through density independent mortality events (such as the effects of ultraviolet light on nuclear polyhedrosis virus persistence) cannot be described by a simple threshold model. However, the effect of disease thresholds and time delays are supported by observations on a range of insect pathogens, including entomopathogenic fungi (Lacey et al ., 1997; Arthurs & Thomas, 2001; Kalsbeek et al ., 2001), viruses (Entwistle et al ., 1983; Woods et al ., 1991; Kukan & Myers, 1997; Hernandez‐Crespo et al ., 1999) nematodes (Campbell et al ., 1998; Mracek & Sturhan, 2000) and Microsporidia (Canning, 1982; Cossentine & Lewis, 1986, 1988; Maddox, 1987; Becnel & Andreadis, 1999).…”