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A population of adult reproductive female brown widow spiders, Latrodectus geometricus Koch (Araneae: Theridiidae) was collected in North Central Florida. Within weeks, the spiders displayed reduced foraging behavior and began to die. A white fungal growth was observed on deceased individuals and others who showed signs of decline. Fungal samples were collected from living spiders as well as from recently deceased specimens. Samples were excised from the spiders and isolated on acidified potato dextrose agar. Morphological characterization was cross referenced with the most recent phenotypic variability studies to confirm probable matches. Molecular identification was rendered using ITS1/5.8S/ITS2 and Mucor fragilis Bainier (Mucorales: Mucoraceae) was indicated with 99% match. Little is documented regarding M. fragilis, and no prior records of pathogenic occurrence are known by the authors. Subsequent bioassay trials supported with 83% mortality that this novel strain of M. fragilis does infect and kill L. geometricus. [ABSTRACT FROM AUTHOR]

The lesser cornstalk borer, Elasmopalpus lignosellus (Zeller) (Lepidoptera: Pyralidae) is an important pest of sugarcane (a complex hybrid of Saccharum spp.) in southern Florida. Reproductive and life table parameters for E. lignosellus were examined at nine constant temperatures from 13 to 36 °C with sugarcane as the larval food source. The pre- and postoviposition periods decreased with increasing temperatures and reached their minimums at 33 and 36 °C, respectively. The oviposition period was longest at 27 °C. The mean fecundity, intrinsic rate of increase (r), and finite rate of increase (λ) were greatest at 30 °C and decreased with increasing or decreasing temperature. The net reproductive rate (R0) was greatest at 27 °C. The Brière-1 model best described the relationship between temperature and r. The generation (T) and population doubling times (DT) were shortest at 33 and 30 °C, respectively. The temperatures around 27 to 30 °C are most favorable for E. lignosellus population growth and significant damage can be expected under these climatic conditions. This data in combination with population monitoring of E. lignosellus under field conditions can be effectively used in population predictions of this pest in field and severe damage can be prevented by timely implementation of control measures. [ABSTRACT FROM AUTHOR]

ABSTRACT Bilibugs (Coleoptera: Curculionidae: Sphenophorus spp.) are common pests whose damage is often misdiagnosed on turfgrass in the United States. Consequently, Florida turfgrass managers have been struggling to satisfactorily control bilibug outbreaks. Thus, we sought to determine the species complex, abundance, seasonality, and fecundity of key Sphenophorus spp. from field collections, and quantify duration of developmental and daily activity periods through greenhouse rearing tests. From January 2006 to December 2007, >18,000 adults of 10 different SphenOpJZOrUS spp. were collected from four linear pitfall traps on each of two golf courses in north central and two courses in southern Florida. Sphenophoru.s venatus vestitus Chittenden was the most abundant species, making up >94% of all specimens collected from three of the four golf courses (80.9% of all specimens collected). Adults were active and mature eggs were present in female ovaries nearly every week of the year. Adults were nocturnal. S. u. vestitus development from egg to adult can occur in 8-9 wk on 'Tifway' bermudagrass [Cynodon dactylon (L.) Pers.] or 'Empire' zoysiagrass (Zoysiajaponica Steud.), with up to six overlapping generations per year, depending on environmental conditions. Thus, any time of year could be suitable to target either adults or larvae, and a repeated application may be needed to manage subsequently emerged larvae or eclosed adults. [ABSTRACT FROM AUTHOR]

Frankliniella spp. (Thysanoptera: Thripidae) thrips damage a variety of crops, feed on a broad range of hosts, and often migrate into cropping systems from adjacent vegetation. To determine potential sources of Frankliniella spp. thrips on crops, annual cycles of abundance of Frankliniella occidentalis (Pergande), Frankliniella fusca (Hinds), Frankliniella bispinosa (Morgan), and Frankliniella tritici (Fitch) were evaluated on seven common, uncultivated reproductive hosts. These hosts included Raphanus raphanistrum L., Rubus trivialis Michx., Rubus cuneifolius Pursh., Vicia sativa L., Trifolium repens L., Solidago canadensis L. and Chenopodium ambrosioides L. Thrips were collected from R. cuneifolius, and T. repens in the spring, R. raphanistrum in the summer, and C. ambrosioides and S. canadensis in the fall. The most common Frankliniella species on every plant species was F. tritici, and a fifth species, Pseudothrips inequalis (Beach), was collected in the fall on C. ambrosioides and S. canadensis. All thrips species were highly aggregated in the flowers or flower racemes, rather than leaves or fruit, and they were generally only collected from flowering plants. R. raphanistrum supported large populations, and they may be an important link for thrips between spring and fall. In addition, it may be an essentially enemy free host, as only one O. insidiosus, an important thrips predator, was collected from this host. S. canadensis also supported large thrips populations in the fall, and it may be a source of thrips migrating into crops the following spring. Controlling thrips on these hosts in their respective seasons may limit the number migrating into cropping systems. [ABSTRACT FROM AUTHOR]

Fall armyworm is a significant agricultural pest in the United States, affecting most notably sweet corn and turfgrass. Two morphologically identical strains, rice strain (R-strain) and corn strain (C-strain), exist that differ physiologically arid behaviorally and can be identified by mitochondrial haplotyping. Recent studies of overwintering populations in Florida indicate that the mitochondrial lineage associated with the R-strain itself consists of two genetically distinct subgroups, with one having molecular markers consistent with interstrain hybridization between R-strain females and C-strain males. To test this possibility and examine the ramifications of interstrain mating on population behavior and strain fidelity, larvae and adult males were tested for genetic marker combinations representative of the host strains and potential hybrids. These studies showed a sexually dimorphic distribution pattern for a sex-linked marker that is a predicted result of interstrain mating. Despite evidence of substantial interbreeding in the overwintering sites, both FR and the strain- diagnostic mitochondrial markers still showed the plant host and habitat biases associated with the host strains, indicating that strain integrity was largely maintained. However, there is evidence that the two R-strain subpopulations differ in habitat distribution in a manner suggestive of the "hybrid" genotype being less specific in its plant host preference. The existence of a genetically distinct hybrid sub- population must be taken into account when evaluating fall armyworm population dynamics and infestation patterns in overwintering areas. [ABSTRACT FROM AUTHOR]