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Sun, X., Stall, R. E., Jones, J. B., Cubero, J., Gottwald, T. R., Graham, J. H., Dixon, W. N., Schubert, T. S., Chaloux, P. H., Stromberg, V. K., Lacy, G. H., and Sutton, B. D. 2004. Detection and characterization of a new strain of citrus canker bacteria from Key/Mexican lime and alemow in South Florida. Plant Dis. 88:1179-1188. In the Wellington and Lake Worth areas of Palm Beach County, FL, citrus canker appeared on Key/Mexican lime (Citrus aurantiifolia) and alemow (C. macrophylla) trees over a period of about 6 to 7 years before detection, but nearby canker-susceptible citrus, such as grapefruit (C. × paradisi) and sweet orange (C. sinensis), were unaffected. Colonies of the causal bacterium, isolated from leaf, stem, and fruit lesions, appeared similar to the Asiatic group of strains of Xanthomonas axonopodis pv. citri (Xac-A) on the nutrient agar plate, but the growth on lima bean agar slants was less mucoid. The bacterium produced erumpent, pustule-like lesions of typical Asiatic citrus canker syndrome after inoculation into Key/Mexican lime, but brownish, flat, and necrotic lesions on the leaves of Duncan grapefruit, Madame Vinous sweet orange, sour orange (C. aurantium), citron (C. medica), Orlando tangelo (C. reticulata × C. × paradisi), and trifoliate orange (Poncirus trifoliata). The bacterium did not react with the Xac-A specific monoclonal antibody A1 using enzyme-linked immunosorbent assay (ELISA) and could not be detected by polymerase chain reaction (PCR)-based assays using primers selected for Xac-A. DNA reassociation analysis confirmed that the pathogen, designated as Xac-AW, was more closely related to Xac-A and Xac-A * strains than X. axonopodis pv. aurantifolii or the citrus bacterial spot pathogen (X. axonopodis pv. citrumelo). The strain can be easily differentiated from Xac-A and Xac-A * using ELISA, PCR-based tests, fatty acid analysis, pulsed-field gel electrophoresis of genomic DNA, and host specificity.

Degree-day models were developed for predicting different levels of attack by slash pine flower thrips, Gnophothrips fuscus (Morgan), on female strobili (flowers) and for predicting the appearance of different morphological stages of flower development. The models were based on 5-yr data collected from a north Florida slash pine, Pinus elliottii Engelmann variety elliottii, seed orchard. Different starting dates and lower threshold temperatures for models were compared. Starting dates included the 1st annual incidence of temperatures below 4.4 degrees C (40 degrees F) and a range of biofix dates (20 November through 10 December). Lower threshold temperatures were compared over a range of -1.1-12.8 degrees C (30-55 degrees F). Degree-day models with a 4.4 degrees C (40 degrees F) lower threshold temperature appeared to be suitable predictors of the appearance of stage 2 flowers and the 50% level of attack by slash pine flower thrips. These models should facilitate implementation of insecticide application programs based on predicting levels of thrips attack and flower phenology.

The small leafmining moth, Phyllocnistis citrella Stainton, was discovered in citrus nurseries in Homestead, FL, on 20 May 1993. During the remainder of 1993, this serious Old World pest of citrus leaves spread to the Florida citrus growing area. By September 1994 it had spread throughout Florida and through much of the Caribbean region, including eastern Mexico; it also had reached southern Louisiana, southern Alabama, and Brownsville, TX. Potential future distribution in the southeastern United States probably will include Gulf Coast areas where winter frost is not severe, with a summer range possibly as far north as tidewater Virginia, wherever homeowner citrus may be found.

The slash pine flower thrips (SPFT), Gnophothrips fuscus (Morgan) commonly damages cone crops of slash pines, Pinus elliottii Engelmann var. elliottii. It occurs in the crowns of seed orchard trees in association with three other species of thrips — Leptothrips pini (Watson), Frankliniella bispinosa (Morgan), and Oxythrips pallidiventris Hood. Pest management strategies are being developed for southern pine seed orchards that rely on the rapid and accurate identification of different species of pests. Two laboratory keys are presented to distinguish the four species of thrips in the laboratory.

The wheat stripe rust pathogen occured on several experimental wheat lines planted at Quincy, FL in early February 2003. Several experimental lines in the 2003 Advanced Wheat A, the Advanced Wheat B, and the Uniform Southern Wheat Nursery yield trials then showed traces of stripe rust on the leaves of the plants. An unusually cool and wet winter and spring encouraged a scattered outbreak of stripe rust of wheat on susceptible experimental lines of wheat. This report constitutes the first documented case of stripe rust of wheat in Florida. Accepted for publication 22 February 2005. Published 4 March 2005.

Insect and disease management is essential for successful regeneration of pines in the southern U.S. Because of the demands imposed by intensive culturing of southern pines, land managers must have a broad working knowledge of entomology and pathology so they can recognize, assess, and remedy many types of insect and disease problems in seed orchards, nurseries, and the field. In seed orchards, insects pose the largest threat to seeds and cones; in nurseries, diseases are the major pest problems; in the field, insects and diseases prevail equally. Regardless of the regeneration management unit, the interactions among insects, diseases, and their hosts must not be overlooked. No control may be warranted when damage is limited to a small part of a single tree; however, various treatments may be necessary when entire seed crops, seedbeds, or plantations are invaded. Wherever possible, preventive measures should be preferred to reactionary treatment because prevention is generally more efficacious. Although pesticides are available for most pests, alternative means — cultural, physical, or biological — should be investigated. In response to heightened environmental awareness, integrated pest management, a holistic approach to solving pest problems, is receiving considerable attention in forestry.

The residual pheromone content of laminated plastic, pheromone-dispensing tapes impregnated with (+)-disparlure, the sex pheromone of the gypsy moth, Lymantria diapar (L.), was assessed after exposure to field conditions in Gainesville. As determined by gas chromatography, lure tapes deployed on 26 August 1991 rapidly lost pheromone during the first 2 months in the field. Loss of pheromone was considerably less for the remaining 4-month exposure period (28 October 1991 to 3 March 1992). Lure tapes at 5 locations differed slightly in their rates of pheromone loss, and traps placed on the north side of tree trunks retained more pheromone than traps placed on the south side. These data indicate that a pheromone lure used for monitoring gypsy moth during spring and early summer in north Florida may lose its effectiveness rapidly and may have to be replaced more often than is currently recommended for other regions of the country.

Life tables (1977–1980) are presented for three generations of the white pine weevil, Pissodes strobi (Peck) (Coleoptera: Curculionidae), a pest insect of eastern white pine, Pinus strobus L. Typically, female weevils oviposited ca. 140 eggs per terminal leader of a host tree in the spring; however, only 1 progeny adult survived to the following spring. Average generation survival (SG = 0.008) and total generation mortality (K = 2.08) reflected observed small increases in weevil infestation each year. Key factor analysis suggested that larval, pupal, and winter submortalities were the major influences on population change. Submortality factors were: (1) egg infertility, (2) pitch-drowning, (3) larval instraspecific competition, (4) natural enemy predation and parasitism, (5) nonemergent brood adults, (6) unknown cause(s) of death, and (7) effect of climatic conditions on overwintering adults.

Spring activities (emergence, feeding, mating, and oviposition) of adult white pine weevils, Pissodes strobi , were monitored weekly from late April to early July 1979. Weevils emerged from overwintering sites in late April. peaked in numbers per tree by mid-May, and none were found on host trees by early July. Activity peaked in early May and appeared to be thermo-photoperiodic. Greatest activity during the 4-h interval checktimes occurred in the late afternoon to early evening (1300 and 1700 h). Adults occupied upper-branch new growth during scotophase, but moved to branch stems during photophase. Weevils are negatively phototactic, and response time to different wavelengths of light varied during scotophase. The weevils occupied the leaders of host trees the first 2 weeks of monitoring. but toward season's end were found more often on first-whorl lateral branches. Length of current-year growth of leaders was influenced by magnitude of weevil damage. Highest levels of immature weevil damage resulted in leader mortality. Leaders that sustained an intermediate level of weevil damage remained alive; however, length of new growth was significantly less than leaders with almost no weevil damage.

Monthly observations of planted slash pines (Pinus elliottii Engelm.) damaged by a March wildfire showed that the magnitude and rapidity of tree mortality were directly related to severity of stem char. Cumulative tree mortalities by November were 5, 25, and 79 percent for 7- to 8-year-old trees in plots with light, medium, and severe stem char classifications (average stem char 80 percent of total tree height, respectively). In 15-year-old plantations the mortality rates were 46, 95, and 100 percent for the three damage classes. Most tree mortality occurred rapidly (before mid-May) in the younger plantations and in the severely damaged portions of the older plantations; mortality rates were slower and continued until August in lightly and moderately damaged areas of the older plantations. Ips engraver beetles and the southern pine sawyer were the principal insects infesting trees in May. Reproduction weevil broods were common in tree roots during November. Implications for pest management are discussed.

Adult weevils occur primarily on current-year apical buds and stems in north and east crown quadrants of upper crown branches. However, some minor movements occurs during the day. Fall adults are found on upper crown lateral branches while spring adults are predominantly located on the terminals of host trees. Weevils overwinter at the interface between an upper dry needle zone and a lower moist organic zone, ca. 20 cm from host tree boles in west and north litter quadrants.

The southern pine beetle (SPB), Dendroctonus frontalis Zimmermann, is the most destructive insect pest of pine in the southern United States. A recent historical review estimated that SPB caused $900 million of damage to pine forests from 1960 through 1990 (Price et a1. 1992). This aggressive tree killer is a native insect that lives predominantly in the inner bark of pine trees. Trees attacked by SPB often exhibit hundreds of resin masses (i.e., pitch tubes) on the outer tree bark. SPB feed on phloem tissue where they construct winding S-shaped or serpentine galleries. The galleries created by both the adult beetles and their offspring can effectively girdle a tree, causing its death. SPB also carry, and introduce into trees, blue-stain fungi. These fungi colonize xylem tissue and block water flow within the tree, also causing tree mortality (Thatcher and Conner 1985). Consequently, once SPB have successfully colonized a tree, the tree cannot survive, regardless of control measures. his document is EENY-176 (originally published as DPI Entomology Circular 369), one of the Featured Creatures series of the Entomology and Nematology Department, Cooperative Extension Service, Institute of Food and Agricultural Sciences, University of Florida. Published: November 2000. Revised: March 2004. EENY-176/IN333: Southern Pine Beetle, Dendroctonus frontalis (Coleoptera: Curculionidae: Scolytinae) (ufl.edu)

Lygus lineolaris (Palisot de Beauvois), the tarnished plant bug, attacks a wide variety of economically important herbaceous plants, vegetable crops, commercial flower plants, fruit trees, and nursery stock (Kelton 1975). In fact, over half of the cultivated plant species grown in the United States are listed as host plants for tarnished plant bugs (Capinera 2001). This document is EENY-245 (originally published as DPI Entomology Circular 320), one of a series of Featured Creatures from the Entomology and Nematology Department, Florida Cooperative Extension Service, Institute of Food and Agricultural Sciences, University of Florida. Published: November 2001. EENY-245/IN513: Tarnished Plant Bug, Lygus lineolaris (Palisot de Beauvois) (Insecta: Hemiptera: Miridae) (ufl.edu)

Tomicus piniperda (Linnaeus), a pine shoot beetle native to Europe, was first discovered in the United States in July 1992, in a Christmas tree plantation in Ohio. Since then, intensive surveying by the U.S. Department of Agriculture and state departments of agriculture has revealed its presence (as of 29 December 2003) in twelve northern states: Illinois, Indiana, Maine, Maryland, Michigan, New Hampshire, New York, Ohio, Pennsylvania, Vermont, West Virginia and Wisconsin (Anonymous 2004b). Because T. piniperda occurs about as far south in the Old World as the latitude of Florida, it is considered a potential threat to at least some of the pine species intensively cultivated in Florida. This document is EENY-321 (originally published as DPI Entomology Circular 354), one of a series of Featured Creatures from the Entomology and Nematology Department, Florida Cooperative Extension Service, Institute of Food and Agricultural Sciences, University of Florida. Published: April 2004. Revised: September 2005. EENY-321/IN596: Pine Shoot Beetle, Tomicus piniperda (Linnaeus) (Insecta: Coleoptera: Curculionidae: Scolytinae) (ufl.edu)

The Nantucket pine tip moth, Rhyacionia frustrana (Comstock), is a serious pest of young pine in plantations, wild pine seedlings in open areas, Christmas tree plantings, ornamental pines, and pine seed orchards in the United States. Growth loss and stem deformity, caused by larvae feeding inside growing shoots, buds, and conelets, can be considerable during the first five years when most damage occurs (Yates et al. 1981). The increasing population of a preferred host species, loblolly pine (Pinus taeda L.), in Florida poses an ever-increasing problem of Nantucket pine tip moth infestations. This document is EENY-304 (originally published as DPI Entomology Circular 298), one of a series of Featured Creatures from the Entomology and Nematology Department, Florida Cooperative Extension Service, Institute of Food and Agricultural Sciences, University of Florida. Published: August 2003. EENY304/IN581: Nantucket Pine Tip Moth, Rhyacionia frustrana (Comstock) (Insecta: Lepidoptera: Tortricidae) (ufl.edu)

Pine sawfly larvae, Neodiprion spp., are the most common defoliating insects of pine trees, Pinus spp., in Florida. Sawfly infestations can cause growth loss and mortality, especially when followed by secondary attack by bark and wood-boring beetles (Coleoptera: Buprestidae, Cerambycidae, Scolytidae,). Trees of all ages are susceptible to sawfly defoliation (Barnard and Dixon 1983, Coppel and Benjamin 1965). This document is EENY-317 (originally published as DPI Entomology Circular No. 258), one of a series of Featured Creatures from the Entomology and Nematology Department, Florida Cooperative Extension Service, Institute of Food and Agricultural Sciences, University of Florida. Published: January 2004. EENY317/IN592: Pine Sawflies, Neodiprion spp. (Insecta: Hymenoptera: Diprionidae) (ufl.edu)