It seems somewhat of a paradox that agondal females would produce a “virus” plug that is able to serve as a source of virus to be transmitted to males ( Burand et al. They also state that infected females produced twice the amount pheromone as control females but failed to substantiate this claim by providing information as to how the pheromone was detected or the amounts of pheromone or pheromone components produced by infected females. (2000a) reported that agonadal females vigorously rejected males that attempted to mate. This loss of receptivity is only temporary and pheromone production may resume on nights subsequent to the night of mating ( Callahan 1958 Kingan et al. After mating, pheromone titers decline and the female loses sexual receptivity due to the transfer of male-derived anti-calling factors, including a pheromonestatic peptide (PSP) ( Kingan et al. This behavior results in the attraction of mates and receptivity to males that attempt to mate by clasping and holding the female's genitalia with their own ( Callahan 1958). This peak in pheromone titer triggers female mating and “calling” behavior, which includes rapid wing vibrating, the extruding of the ovipositor and release of sex pheromones via the pheromone gland ( Raina et al. The production of pheromone begins during the first scotophase following adult emergence and peaks during the second and third nights. zea is thought to be regulated by the level of sex pheromone produced by the female. As with most insects, the mating pattern of H. The process of finding and attracting suitable mates is the focal point of insect reproductive behavior. We have recently demonstrated that the “virus” plug can serve as a source of contaminating virus, which healthy males can acquire upon contacting agonadal females and then transmit to other females during subsequent matings ( Burand et al. Upon the emergence of these infected female moths, the associated material appears to coalesce around the virus particles and form virus-filled vesicles that make up a clearly visible “virus” plug that can be found covering the tip of the vulva of agonadal females ( Rallis and Burand 2002b) and used to easily identify virus infected females. In agonadal females, virus replication occurs primarily in the oviducts leading to the proliferation of cells in these tissues and production of a large number of virus particles that accumulate in association with a matrix of darkly staining material in the cervix bursae. Hz-2V replication in host reproductive tissues results in the malformation of these tissues and sterility of infected moths, a condition that has been termed agonadal ( Raina and Adams 1995). They also demonstrated that Hz-2V could be horizontally transmitted during mating and suggested that the induction of virus replication and vertical transmission by asymptomatic females was linked to mating. (1996) showed that persistence of Hz-2V in the Stoneville colony was related to the fact that some female moths in the colony were fertile, asymptomatic carriers of the virus and that these females could vertically transmit the virus to their progeny inside eggs. Therefore, in keeping with the present system used to name these types of viruses we propose to name this new virus more appropriately Hz-2V. 2002) indicates that these two viruses are very closely related. This virus is a rod shaped, enveloped virus that resembles Hz-1V in size, pathology in vitro, and in genome structure and size ( Burand 1998) and, in addition, a comparison of the genome sequence of this virus (Burand unpublished) with the sequence of the genome of the Hz-1V ( Cheng et al. Hence, the tropism and replication of the virus is not specific for gonadal tissues. (1996) as well as by Rallis and Burand (2002a, 2002b) demonstrated that GSV replicates in a variety of male and female reproductive tissues, including common and lateral oviducts. This virus was found to replicate exclusively in the reproductive tissues of infected moths and was initially named gonad-specific virus (GSV) ( Raina and Adams 1995). A colony of corn earworm moths, Helicoverpa zea, from Stoneville, Mississippi was found to be persistently infected with a virus for over five generations ( Herzog and Philips 1982 Hamm et al.
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