Treesearch

Survival, development time and pupal weights of gypsy moth, Lymantria dispar L., which had fed on southern tree hosts were determined. Five species of oaks, Quercus spp.; sweetgum, Liquidambar styracflua L.; and river birch, Betula nigra L., were found to be acceptable hosts. Survival and female pupal weights were significantly higher and development times were significantly shorter for larvae fed on water oak, Q. nigra L., than for any other species.

Research in western Massachusetts, on Cape Cod, and on Bryant Mountain in Vermont conducted over the past decade has confirmed the importance of mortality during the late larval and pupal stages to gypsy moth population dynamics.

Retrotransposon screen: Gypsy moth families containing straggling and nonstraggling individuals were divided into categories of straggling, medium, and nonstraggling individuals, from which DNA was extracted. Four families were tested by southern hybridization and probing with ribosomal sequences designed to detect R1 and R2 retrotransposon insertions. Results showed no differences between stragglers and nonstragglers in the proportion of insertions in their ribosomal genes. The average proportion of insertions was 30%.

Many potentially useful insecticides and herbicides undergo relatively rapid degradation on exposure to sunlight.

Gypsy moth (Lymantria dispar L.) egg phenology has been described as being comprised of three phases: pre-diapause morphological development, diapause, and post-diapause morphological development.

The treatment implementation advisor is one of the knowledge based advisory modules of GypsES, a knowledge system environment for decision support in gypsy moth management. Its function is to provide detailed advice on intervention tactics for gypsy moth: e.g. aerial and ground application of insecticides and microbials, inundative or augmentative releases of parasitoids, mating disruption, genetic control and silvicultural management.

Baculoviruses such as the Lymantria dispar nuclear polyhedrosis virus (LdMNPV) are ecologically attractive alternatives to chemical insect pesticides but have a slow rate of control. To overcome this we have developed and are field testing an environmentally acceptable strategy which can be used for the introduction and expression of pesticide-enhancing genes by baculoviruses. The field release data will be used to construct environmentally-safe, viral pesticides which have improved pesticidal properties and which will not persist in nature.

The Blackmo 88 spray trial experiment was conducted for two primary purposes: To quantify the effects of local micrometeorological processes, in and near the canopy, on the deposition patterns of aerially applied BT in a mature oak forest; To generate a data set containing simultaneous measurements of spray deposition and detailed micrometeorology, in a canopy of known structure, that could be used to verify the FSCBG spray deposition and penetration model in oak forests.

The incidence of nuclear polyhedrosis virus in gypsy moth populations is currently measured by rearing field-collected larvae until death.

The gypsy moth, Lymantria dispar, is not particularly susceptible to baculoviruses other than the nuclear polyhedrosis virus originally isolated from the species (LdMNPV). The multiple enveloped nuclear polyhedrosis virus of Autographa californica (AcMNPV), a very virulent baculovirus that replicates in a large number of Lepidopteran species, only rarely produces mortality in gypsy moth larvae regardless of the dose ingested.