Biological Control of Spider Mites in Long Island Vineyards

NYS IPM Type: Project ReportThe mite Typhlodromus pyri can, where it is conserved, provide complete biological control of European red mite. We released T. pyri into vineyards on Long Island in 1996 and into an additional two vineyards in 1997. Typhlodromus pyri were recovered from all four release locations. Where the predators were released in 1996, T. pyri numbers were relatively high in early summer during 1997, but then declined in number. At one of these sites T. pyri apparently provided biological control of European red mite. Where T. pyri were released in 1997, the predators were moderately abundant during the entire season. At both of these locations T. pyri provided biological of European red mite. Typhlodromus pyri were also recovered from plots where the predators were not released. This suggest that T. pyri are endemic to Long Island vineyards, but are probably not as resistant to certain pesticides as those predators from Geneva, NY

Characteristics of cell fusion induced by a caprine retrovirus

The mechanism of cell-fusion induced by caprine arthritis-encephalitis virus (CAEV) was investigated. Following infection with concentrated CAEV, cell fusion occurred prior to the production of infectious progeny virus. The time of initial detection of cell fusion was dependent on the multiplicity of infection and was not detected until 5 hours after infection. The virus-induced cell fusion was only partially inhibited by ultraviolet irradiation of the virus and was not inhibited by cytosine arabinoside. The results indicated that fusion by CAEV was a slow response to direct interaction of input virus with cells (fusion from without) and that virus replication was not required

Eradication of black rot (Guignardia bidwellii) from grapevines by drastic pruning

A drastic pruning strategy was developed to eradicate the fungal disease black rot (Guignardia bidwellii), which is exotic in Australia, from grapevines, while minimizing the economic cost of returning an affected vineyard to its previous quality and production levels. The protocol involved cutting off vines at the top of the trunk, removing debris from the ground beneath and between vines, mulching the vineyard floor, removing low watershoots during vine regrowth and applying a targeted fungicide programme. The protocol was initially evaluated and consequently modified in Australia using an endemic grapevine disease, black spot or anthracnose (Elsinoe ampelina), as an analogous model system. Then, it was validated in a black‐rot‐infested vineyard in New York, USA. Following two seasons of disease‐conducive weather conditions, no black rot was detected on treated vines, whereas leaf and fruit infections developed on the untreated control vines. These results confirmed the efficacy of the protocol for eradicating black rot from vineyards while allowing vines to return quickly to previous yield and quality levels without replanting. The protocol may have applicability to disease eradication protocols for other perennial crops as well. Evidence is also presented on the efficacy and potential pitfalls of burning infected grapevine material to eradicate E. ampelina.M. R. Sosnowski, R. W. Emmett, W. F. Wilcox, T. J. Wick