The gypsy moth, Lymantria dispar (L.) (Lepidoptera: Lymantriidae) nucleopolyhedrovirus LdMNPV was tested as a synergist for nucleopolyhedroviruses against Helicoverpa zea (Boddie), Spodoptera exigua (Hübner), and Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae) larvae. The addition of the gypsy moth NPV significantly decreased the LC50s of AcMNPV, AfMNPV, GmMNPV, HaMNPV, HzSNPV, PxMN...

Trees in the genus Populus can provide substantial commercial and ecological benefits, including sustainable alternatives to traditional forestry. Realization of this potential requires intensive management, but damage by defoliating insects can severely limit productivity in such systems. Two approaches to limiting these losses include cultivation of poplar varieties with inherent resistance t...

The effects of asynchrony in the phenology of spring-feeding insect-defoliators and their host plants on insects' fitness, as well as the importance of this effect for the population dynamics of outbreaking species of insects, is a widespread and well-documented phenomenon. However, the spreading of this phenomenon through the food chain, and especially those mechanisms operating this spreading...

Two regression estimators were developed for determining densities of late-instar gypsy moth, Lymantria dispar (Lepidoptera: Lymantriidae), larvae from burlap band and pyrethrin spray counts on oak trees in Vermont, Massachusetts, Connecticut, and New York. Studies were conducted by marking larvae on individual burlapbanded trees within 15-m diameter plots and recapturing them with pyrethrin sp...

Examining dead insects from different locations in Mazandaran, Gilan and TehranProvinces, specimens with fungal outgrowth were selected for further investigations. After isolation and purification of fungi they were identified as follows:Beauveria brongniartii (Sacc.) Petch*On Coccinella septempunctata, Tehran Prov., Varamin, Ghara-Aghaj mountains, M.H. Ghassemi (IRAN 1025 C). Paecilomyces tenu...

The midgut pH of gypsy moth (Lymantria dispar) larvae was significantly lower when larvae were fed acidic foliage. At 30 min after the start of a feeding bout, larvae feeding on bigtooth aspen (foliage pH = 6.04) had average midgut pH levels of 10.16, while larvae feeding on red oak foliage (foliage pH = 3.84) had average midgut pH levels of 9.36. Midgut pH was also significantly reduced when l...

Spotted Lanternfly, Lycorma delicatula (White) is a recently introduced pest of Tree-of-Heaven, Ailanthus altissima (Mill.) Swingle in North America. Natural enemy surveys for this pest in Pennsylvania in 2016 recovered an encyrtid egg parasitoid from both field collections and laboratory rearing of field-collected L. delicatula egg masses. Both molecular and morphological data confirm that the...

The gypsy moth (Lymantria dispar L.) nuclear polyhedrosis virus was genetically engineered for nonpersistence by removal of the gene coding for polyhedrin production and stabilized using a coocclusion process. A beta-galactosidase marker gene was inserted into the genetically engineered virus (LdGEV) so that infected larvae could be tested for its presence using a colorimetric assay. In 1993, L...

We formulate a novel host parasite model to study the dynamics of the outbreak of the gypsy moths. Assuming a Ricker dynamics for the host population and an infestation that takes place after the growth limitations take effect in the plant dynamics, a two dimensional discrete model of the leaf mass and the gypsy moths mass is constructed. The parameter space is determined by the growth rate of ...

Predation is an important factor in the dynamics of gypsy moth (Lymantria dispar L.) populations, yet predation rates can be difÞcult to estimate accurately in the Þeld. Biased estimates can result from spatial heterogeneity in risk or from artifacts associated with deploying prey. Here we compare predation rates on freeze-dried gypsy moth pupae afÞxed with beeswax to pieces of burlap withpreda...