2001 Annual Report 1.What major problem or issue is being resolved and how are you resolving it? Exotic aquatic, wetland, and terrestrial plants invade agricultural and natural ecosystems in Florida and throughout the United States. These weeds impede agricultural drainage and irrigation activities, interfere with flood control efforts, infest pastures and crop lands, and displace the native flora and fauna in natural areas. Invaders like Melaleuca quinquenervia and Lygodium microphyllum pose significant impediments to Congressionally mandated efforts to restore Florida's Everglades, and are so damaging that they helped prompt Presidential Executive Order 13112 directing all federal agencies to make invasive species a national priority. We are developing and implementing biological control agents that damage these plant invaders, thereby inhibiting reproduction, slowing plant growth, reducing population sizes, and lessening negative impacts in agricultural lands and natural areas, including those comprising the Everglades. 2.How serious is the problem? Why does it matter? Melaleuca currently infests about 400,000 acres of Florida's Everglades and invades bordering pasture lands. Lygodium occurs on over 100,000 acres, a fivefold increase in just over 5 years, and threatens to become the Kudzu of the South. Tropical soda apple (Solanum viarum) infests thousands of acres of pastures and natural prairies in Florida and has spread into much of the southeastern U.S. Brazilian peppertree (Shinus terebinthifolius) infests over 1 million acres in Florida and Hawaii. The submersed weeds Hydrilla verticillata and Myriophyllum spicatum (Eurasian watermilfoil) occur in over 40 states and infest several hundred thousand acres of waterways. Waterhyacinth (Eichhornia crassipes) infests tens of thousands of acres in the Gulf Coast states. Efforts to control these and other invasive plant species cost tens of millions of dollars annually in Florida, and hundreds of millions of dollars nationally. In addition, species like Melaleuca and Lygodium threaten the biodiversity of Florida's Everglades which, because it is so unique, has been designated a World Heritage ecosystem by UNESCO, an International Biosphere Reserve, and a RAMSAR site. 3.How does it relate to the national Program(s) and National Program Component(s) to which it has been assigned? This project is related to two National Programs: the Crop Protection & Quarantine Program [NP304] (the Biological Control of Weeds, Weed Biology & Ecology, and Weed Management Systems Components) and the Water Quality and Management Program [NP201] (Agricultural Watershed Management Component). It also fulfills Objective 3b in section III.C.1 of the USDA Strategic Plan non Noxious Weeds, pertains to Presidential Executive Order 13112, and addresses National Goal #2 of the National Strategy for Invasive Plant Management endorsed by more than 100 organizations and governmental agencies including USDA. The project seeks to improve understanding of invasive weed biology and of weed/biocontrol insect interactions so as to integrate biological control agents into IPM strategies for controlling these pest plants which invade agricultural and natural ecosystems, interfere with irrigation and flood control efforts, and degrade water quality in Florida's Everglades. Collaborators include the US Army Corps o Engineers, South Florida & Southwest Florida Water Mgmt Districts, Florida Dept of Environmental Protection & the University of Florida. 4.What was your most significant accomplishment this past year? A. Single Most Significant Accomplishment during FY2001 year: The Australian tree Melaleuca quinquenervia was introduced into Florida in 1886 where it escaped cultivation and naturalized in the southern part of the state. The aggressive invasion by M. quinquenervia, and subsequent ecological damage, appears to be attributable to its inherent ability to produce copious (massive) amounts of seeds so we released the biological control agent Oxyops vitiosa into Florida in 1997 to suppress the weed and possibly reduce seed production. Four years later, ARS scientists have determined that attacked trees produce fewer flowers regardless of tree size, with production reduced by as much as 90%. This reduction in M. quinquenervia flower and seed production limits continued invasion of pristine natural areas, such as the Everglades ecosystem, as well as those areas already treated chemically by local water rmanagement districts. B. Other Significant Accomplishments, if any: C. Significant Accomplishments/Activities that Support Special Target Populations: D. Progress Report: Melaleuca ecological studies. Studies comparing melaleuca forests in Australia and Florida show few differences in standing biomass or litter throughfall, suggesting that productivity is similar in both adventive and native areas. Trees in the US, however, allocate more than twice the proportion of total biomass into regeneration, which explains the more invasive character of Florida populations. Capsule and seed production is over 10-fold higher in the US compared to Australia. Further, high flower bud abortion caused by direct damage from bud-feeding insects in Australia results in lower numbers of capsules per unit of infructescence length (3.2 capsules/cm in Australia vs. 8.2 capsules/cm in Florida). We have now also demonstrated an indirect effect of herbivory by the weevil Oxyops vitiosa Pascoe, where seed production by affected trees has been severely curtailed. Thus, sustainable econtrol of melaleuca seems dependent upon restraining seed production, which is a plastic trait vulnerable to manipulation. Melaleuca seeds tend to be more viable and germinate more frequently in the US than in Australia (9.1% vs. 3.3%, and 7.8% vs. 2.8%, respectively). In the US, seed rain is continuous year round with about 268 million seeds falling per hectare per year. Similar data are now being collected in Australia but are not yet available for comparison. About 3% of buried seeds remained viable at dry sites after more than 1.5 years in the soil. However, seeds placed at wet sites germinated quickly, so soil seed banks are probably non-existant in aquatic habitats but provide a significant source of reinvasion under drier conditions. Melaleuca biocontrol agent development. The Australian melaleuca snout beetle Oxyops vitiosa was first released during 1997. Habitats with abundant young foliage on the trees, short hydroperiods, intermediate stages of melaleuca invasion, and dry winter conditions engendered field-colony development. Transect sampling estimate the population at more than 2000 adults and 22,000 larvae during October 1998, one year after release of 3300 larvae at a 8-ha pasture near Estero, Florida. By June 2000, numbers swelled to over 100,000 adults and nearly 64,000 larvae. Adults decreased during December 2000 after the field was cut, but the larval population exceeded 210,000. Adults and larvae are continuously being collected from this site and relocated. Approximately 200,000 weevils have been released at 150 sites thus far, and populations of O. vitiosa are now widely established in southern Florida. Tip dieback is becoming evident, trees are appearing defoliated due to the lack of replacement foliage, and some smaller trees are apparently dying. Also, trees that have suffered the severest damage for the longest time are no longer producing flowers. Dispersal has been slow, however, and wide scale infestation remains dependent upon manual redistribution. The performance of the biological control agent Oxyops vitiosa was significantly decreased when fed one of the two Melaleuca quinquenervia chemotypes. Larval survival growth, development and adult fecundity were reduced when fed a chemotype prevalent on the east coast of Florida characterized by relatively high concentrations of the sesquiterpene viridiflorol compared with the chemotype that occurs mostly on the west coast of Florida characterized by the sesquiterpene trans-nerolidol. Moreover, anti-predator defenses of O. vitiosa are characterized by terpenoids sequestered from their host plant M. quinquenervia. These sequestered terpenoids vary according to those that are available in the host chemotype. The M. quinquenervia volatile terpenoid that has the greatest electrophysiological response by both sexes of adults is a- terpineol. Both chiral forms of the terpenoid are perceived with equally high intensity. Evaluation of a melaleuca sawfly (Lophyrotoma zonalis) determined that it was host-specific to melaleuca. However, two toxic peptides were identified din the larvae. These peptides have been implicated in livestock poisonings by related sawfly species in Europe, Australia, and South America so plans for the release this agent are on hold until the risks associated with these toxins can be more fully assessed. Host range studies were completed with Boreioglycaspis melaleucae (an Australian psyllid) and a proposal for field release was submitted to the USDA Animal and Plant Health Inspection Service (APHIS) during March 2000. The petition was reviewed and the interagency Technical Advisory Group (TAG) recommended release of the psyllid during June 2000. The U.S. Fish and Wildlife Service completed a Biological Assessment (BA) during June 2001 in which it concurred with the TAG recommendation. Issuance of a permit is now awaiting completion of an Environmental Assessment by APHIS. These psyllids feed on the phloem and heavy nymphal feeding kills saplings. The family Fergusoninidae includes only the genus Fergusonina, which contains flies that, in mutualistic associations with nematodes, induce galls on several species of Australian Myrtaceae. Both leaf bud and flower bud galls are produced. Injection of nematodes (N = 30) into leaf bud tissue suggested that the nematodes, not the flies, initiate gall formation. Female flies deposited juvenile nematodes along with fly eggs into apical regions of developing buds inducing formation of hypertrophied, uninucleate plant cells before the fly eggs hatch. Fly eggs hatched after 44 days when external gall morphology became more pronounced. These galls act as nutrient "sinks" preventing the plant from diverting nutrients away from damaged shoots to undamaged buds, as would normally occur. The available photosynthate nutrifies the gall, which feeds and shelters both flies and nematodes. This competition between galls and meristems for available photosynthetate will further curtail flower production and enhance traditional control measures. Comparisons of DNA sequences from flies and nematodes showed that most attack only a single host plant species. Molecular analysis resulted in clear resolution of species and the relationships among them. Results show that the degree of host specificity of fergusoninids is high, with most species associated with a single host plant species. Information from these studies will be used together with host specificity screening to support a request for release of the M. quinquenervia fly/nematode system in Florida. Host range studies have demonstrated the specificity of the Fergusonina sp. associated with M. quinquenervia in Australia. This fly is now being tested din quarantine on native species of Myrtaceae. Controlled studies revealed that flies make wounds with their ovipositors that leave characteristic scars that can be used to diagnose and detect ovipositional activity. Ovipositional specificity should be the only testing needed because the host is selected entirely by the adult female during the process of oviposition. The resultant immobile larvae remain within the gall, unable to switch hosts. Lygodium biocontrol agent development. Host screening of the Lygodium moth Cataclysta camptozonale was nearly completed, demonstrating to date that the moth is specific to species in the genus Lygodium. An AFLP study has been initiated to determine the geographic origins of Florida's L. microphyllum. Determination of origins should help focus the search for biocontrol agents to a smaller region and produce more adapted and therefore presumably more efficacious agents. Also, a molecular taxonomic study has begun to determine the relationships between different species of Lygodium. Understanding these relationships should be useful in choosing species for the host range study of Lygodium biocontrol agents. Biological control of Cactoblastis. An analysis of the potential of biological control of the invasive insect Cactoblastis cactorum was made of various kinds of biological control and natural enemy options, followed by a ranking of relative ecological risks of these approaches and various types of natural enemies. This research is expected to be the basis of future biological control research against the moth. Biological control of skunkvine. A two-year feasibility study was completed examining the feasibility of biological control of skunk vine, an invasive weed in Florida, which indicated biological control has good potential for skunk vine control with honly modest levels of risk to economic or native plants. Salvinia biocontrol agent development. Screening of South American samples using RAPDs revealed difficulty in finding any single marker or small set of markers which could identify the members of the Salvinia auriculata species complex. RAPDs could easily identify the S. molesta biotype which has been invasive around the world. Sequencing work by colleagues at the Australia Biological Control Lab indicates the problem of separating members of the complex may be due to multiple hybridization events in an autopolyploid series. This has implications in that biocontrol agents may be may be most efficacious if chosen based on the origin of the infestation and biocontrol agent and less on the species of the infestation. A RAPDs study of S. minima samples from Florida, Georgia, South Carolina, Mississippi, Alabama, Louisiana, and Texas focused on the degree that these einfestations differ at the molecular level. Analysis is currently ongoing, however preliminary indications show considerable overlap in the population structures along with some distinctive outlier individuals. The issue of population structure of the plants will help address whether Cyrtobagous collected in Florida will have the potential to be effective elsewhere. DNA from specimens of the 4 species in the S. auriculata complex from South hAmerica has recently been analyzed along with S. molesta from several adventive localities in the U.S and from South Africa as well as specimens of S. minima from the U.S. and from South America and the two old world species S. cucullata and S. hastate. The Old World Salvinia species were found to form a lineage that is clearly separate from the New World species. Likewise, S. minima represents a lineage that was clearly separated from the S. auriculata complex. However, separation of species within the S. auriculata complex (S. auriculata, S. molesta, S. biloba, and dS. hertzogii) was not so clear. All Salvinia molesta specimens from the adventive localities (California, Texas, Louisiana, Florida, and South Africa) were identical and grouped most closely with S. hertzogii. In contrast, the South American S. molesta differed from the adventive S. molesta and grouped with S. auriculata and S. biloba. Salvinia molesta and S. herzogii are putative hybrids (pentaploid and septaploid, respectively) which may explain the miscegenous nature of these results. The Salvinia weevil Cytrobagous salviniae is one of the most successful biological control agents ever deployed, having controlled Salvinia molesta in at least 12 countries on 3 continents. It occurs in Florida where it was accidently introduced before the 1960s probably in association with the introduction of S. minima. Weevils collected from S. minima in Florida were released in Texas on S. molesta, but numbers were low and site disruptions and permit issues preempted further attempts. Meanwhile, DNA sequence data were acquired for weevils from Florida and Australia (ex. Brazil). Differences were found (10 base pairs out of 572 and 566 examined) on the D2 expansion domain of the 28s rRNA gene. The significance of these differences is unclear, but they may indicate that genetically identifiable biotypes of the weevils exist with Florida weevils specialized to use S. minima and not well adapted to survive on S. molesta. We now intend to release weevils used in Australia, which have a proven track record, in future attempts to control S. molesta. Host testing revealed that the Old World Salvinia species were unacceptabl hosts for Australian-type C. salviniae. Within New World species, substantial adult feeding occurred on S. minima but it was unacceptable as a larval host. Only S. molesta supported both larval development and adult feeding. No other aquatic fern species (Marsilea spp. or Azolla spp.)were used in any fashion. Thus, we conclude that only species in the S. auriculata complex can support population development of this species. This was documented in a petition submitted to APHIS requesting permission to release C. salviniae from Australia. Biological control risk assessment. An analysis of the ecological risk associated with biological control of insects and weeds was completed. Understanding risk should lead to improved biological control practice. Safer practice will protect biological control, which is critically needed to combat invasive species in agriculture and conservation. Also, an analysis of risk associated with biological control of weeds in Hawaii was done to clarify the risk to native plants and to can help focus biological control programs on invasive weeds that are distantly related to Hawaii's unique flora. This will allow control of most invasive weeds, which threaten the flora, to take place without harm to native flora. Waterhyacinth biological control studies. The North American noctuid moth Bellura densa Walker offers promise as a classical biological control agent for use in Africa and other countries suffering from severe water hyacinth infestations. An augmentative release at a pond in Florida demonstrated that it could eliminate water hyacinth within a few months. These results prompted studies on host usage patterns by this insect. Larvae damaged 87% of the pickerelweed compared to only about 5% of the taro at a site containing a mixture of 97% taro and 3% pickerelweed, suggesting "spillover" onto taro. Use of Peltandra virginica (L.) Schott & Endl. (Araceae) was evident at another site. Three months after 416 larvae were liberated into a concrete tank containing water hyacinth (818 plants) surrounded by taro (96 plants), water hyacinth comprised 96% of the damaged plants whereas taro comprised only 4%. In a similar study, larvae were liberated onto water hyacinth in a large tank divided into thirds, with pickerelweed or taro at either end and water hyacinth in the middle. The distributions of F1 egg masses and incidence of damage 3 mos. later indicated that pickerelweed was preferred over taro, but 26% of the taro plants were damaged. While B. densa prefers plants in the Pontederiaceae, it is not host-specific. Plants in the Araceae would be at risk if this insect were released outside of North America, particularly in cropping situations near water hyacinth infestations. It should not be released in African countries, but it could be useful in the U.S. if effective augmentation strategies were developed. The performance of the previously introduced weevils, Neochetina bruchi and N. eichhorniae, were compared by assessing their effects on competition between waterhyacinth and waterlettuce. The waterhyacinth plants were pre- stressed by exposing them to equal numbers of either N. eichhorniae or N. bruchi or both. After 3 months, the stressed plants were placed in tanks with waterhyacinth at varying densities of both plants. Controls were established by treating one set of waterhyacinth with insecticide. In high- nutrient controls, waterhyacinth consistently out-competed waterlettuce. However, either N. bruchi or both species in combination virtually eliminated waterhyacinth's ability to compete, which enabled waterlettuce to dominate. Infestation by N. eichhorniae, on the other hand, had little impact. Stress from nutrients or crowding increased flower production, but stress from either species of weevil reduced flower production. Thus, under high nutrient conditions, N. bruchi seems to be a superior biological control agent compared to N. eichhorniae, but both have important effects. Florida populations of the waterhyacinth weevils Neochetina bruchi and N. eichhorniae are infected with a microsporidia disease that allegedly reduces their ability to control the target weed. Research has recovered two primitive species of microsporidia infecting each weevil host. 5.Describe your major accomplishments over the life of the project, including their predicted or actual impact? Prior to the establishment of this project studies of Florida populations of Melaleuca quinquenervia established baseline information concerning reproductive output, standing biomass estimates, monthly litterfall quantities and composition, and general plant phenology. These data are the basis for evaluating performance by melaleuca biocontrol agents, including the Australian weevil Oxyops vitiosa which was first released in 1997 and has since been redistributed at over 150 sites in southern Florida. The host fidelity of three other agents,the sawfly Lophyrotoma zonalis, the psyllid Boreioglycaspis melaleucae, and the leaf-blotching bug, Eucerocoris suspectus was studied in US quarantine. Other potential bioagents were studied in Australia, and a survey was conducted for pathogens that might be useful. Molecular studies confirmed that each species of Fergusonina gall fly is associated with a single species of melaleuca. Three species of faquatic snout-beetles, or weevils, from Thailand and three species from China were evaluated in quarantine for their potential as control agents of the submersed aquatic weeds, hydrilla or Eurasian watermilfoil. However, none were found to have potential for field release. Surveys were also initiated for natural enemies of the Old World climbing fern, Lygodium microphyllum. 6.What do you expect to accomplish, year by year, over the next 3 years? During FY2002, the Australian melaleuca psyllid will be released from quarantine for control of melaleuca. We will collect and characterize volatiles from the target weeds Melaleuca quinquenervia and Eichhornia crassipes, and also from the biocontrol agents Neochetina eichhornia and N. bruchi. Competition studies will provide a scale for measuring waterhyacinth biocontrol insects impact by comparing to Neochetina effectiveness. Quantification of differences in biomass allocation between Florida and Australia will allow us to evaluate effectiveness of released biocontrol agents. Molecular techniques will be used to determine (1) which worldwide accessions of Lygodium are most closely associated with US populations, and (2) to clarify the taxonomic status of Cyrtobagous species from Florida, Australia, and South America. Results from host screening studies will be used to determine whether C. camptazonale is safe and, if so, a release petition will be written and release sites will be selected and evaluated. A proposal for release of a third melaleuca biological control agent, a gall-making fly, is expected to be approved. We will assess the safety of the lygodium moth in the genus Mustoma. We will complete field host range trials with Puccinia psidii. We will finish and publish research to predict which kinds of plants become invasive weeds in Florida. We will initiate explorations for natural enemies of skunk vine. A new Australian melaleuca insect, probably a leaf-defoliating caterpillar, ,will be colonized in quarantine and host range tests begun. A proposal for release of an Australian leaf-defoliating caterpillar on Old World climbing-fern will be submitted to APHIS depending on results of final testing. A second Australian leaf-defoliating caterpillar will be colonized on the fern in quarantine for host range testing. During FY2003, we will use molecular techniques to analyze the population genetics of Salvinia species. Bioassays will help us identify which volatiles produced by Melaleuca quinquenervia and Eichhornia crassipes act as stimulants for oviposition by their respective biocontrol agents. Bioassays will also help us determine whether Oxyops vitiosa or either Eichhornia species produces aggregation pheromones derived from their host plant's volatiles. The host range testing of the two Australian leaf- defoliating caterpillars on melaleuca and climbing-fern should be completed. Mass rearing techniques will be developed to speed deployment of biological control agents. New information systems will facilitate technology transfer and the collection and dissemination of Salvinia sp. Analysis of disparities in reproductive output between Australia and Florida will permit us to quantify melaleuca bioagent efficacy. We will also describe the influence of invasive species on successional changes in native Everglades plant communities. We will do research to understand and predict the possible movement of biological control agents from Florida to the Caribbean. During FY2004, proposals for release of the two caterpillars will be prepared, if testing results warrant, and submitted to APHIS. Additional melaleuca and climbing-fern insects will be imported to quarantine for host range tests. We will evaluate quarantine-based predictions of host specificity for the weed biological control agent Oxyops vitiosa. Assess the reproductive development, physiological age and influence of plant phenology on egg production of Oxyops vitiosa. Determine if the introduced biological control agent Oxyops vitiosa has acquired native predators, parasites and pathogens in its adventive range and assess the impact of these novel trophic interactions. Evaluate the influence of temperature, photoperiod and humidity on the development of Oxyops vitiosa to assist in predicting population trends (degree-day model) under field conditions. Release and establish Boreioglycaspis melaleucae. Quantify preliminary impacts of Boreioglycaspis melaleucae on the invasive tree Melaleuca quinquenervia. Survey the Acari associated with the invasive plants Salvinia minima and Brazilian peppertree to predict negative interactions with potential biological control agents. 7.What technologies have been transferred and to whom? When is the technology likely to become available to the end user (industry, farmer other scientist)? What are the constraints, if known, to the adoption durability of the technology? Federal, state, and local land managers in Florida have been assessed of the operational status of the melaleuca biocontrol agent Oxyops vitiosa. Techniques for collecting and redistributing this insect have been taught to these land managers, as well as private landholders and weed control specialists. We have also collaborated with land managers and private landholders to redistribute at Salvinia infestations in Texas weevils (Cyrtobagous salviniae) collected in Florida. Developed and distributed a brochure on biocontrol of giant salvinia, and contributed to web page about same. Taught sessions on the use of operational weed biocontrol agents at the University of Florida's Aquatic and Wetland Weed Control Short Course. Presentations before environmental organizations, scientific organizations, and federal and state working groups appraised administrators and scientists of the importance and availability of biological control agents for use against invasive weeds, and helped assure the inclusion of weed biocontrol technology in federal and state management plans. Available quarantine space is inadequate for testing host fidelity of several species at once. Thus, lack of adequate quarantine facilities is the greatest constraint to developing additional biocontrol insects for use against invasive weeds of the southeastern U.S. Also, technical support is woefully inadequate, requiring scientists to perform duties typically assigned to technicians and thereby delaying results. Projects could move more quickly to solution of problems with greater technical support. 8.List your most important publications and presentations, and articles written about your work (up to three total --NOTE: this does not replace your review publications which are listed below) Florida Fish and Wildlife Service 5th Annual Exotic Plant Workshop, December 14, 2000, Naples, FL. University of Florida IFAS Aquatic and Upland Invasive Plant Research and Extension Review, March 7-8, 2001, Palm Coast, FL. University of Florida IFAS Aquatic Weeds Short Course, May 14, 2001, Boca Raton, FL. Florida Exotic Pest Plant Council Annual Symposium, September 12-14, 2001, St. Augustine, FL. Review Publications Bennett, C.A., Buckingham, G.R. The insect fauna of a submersed weed, Hydrilla verticillata. Spencer, N.R., editor. Proceedings X International Symposium on Biological Control of Weeds, July 4-14, 1999. 2000. p. 307- 313. Buckingham, G.R. The Australian sawfly Lophyrotoma zonalis, a potential agent for control of Melaleuca quinquenervia in Florida. Spencer, N.R., editor. Proceedings X International Symposium on Biological Control of Weeds, July 4-14, 1999. 2000. p. 421. Center, T.D., Van, T.K., Rayachhetry, M., Buckingham, G.R., Dray, F.A., Wineriter, S.A., Purcell, M.F., Pratt, P.D. Field colonization of the melaleuca snout beetle (Oxyops vitiosa) in south Florida. Biological Control. 2000. v. 19 pp. 112-123. Dray, F.A., Center, T.D., Wheeler, G.S. Lessons from unsuccessful attempts to establish Spodoptera pectinicornis (Lepidoptera: Noctuidae), a biological control agent of waterlettuce. Biocontrol Science and Technology. 2001. v. 11. p. 301-316. Giblin-Davis, R., Center, B., Makinson, J., Purcell, M., Scheffer, S., Thomas, W.K., Davies, K., Taylor, G., Morris, K., Goolsby, J., Center, T. The Fergusobia/Fergusonina gall-forming complex for biocontrol of Melaleucaquinquenervia in Florida. Journal of Nematology. 2000. (abstract) v. 32. pp431 Madeira, P.T., Jacono, C.C., Van, T.K. Monitoring hydrilla using two RAPD procedures and the nonindigenous aquatic species database. Journal of Aquatic Plant Management. 2000. v. 38. pp. 33-40. Montgomery, B.R., Wheeler, G.S. Anti-predatory activity of the weevil Oxyopvitiosa: a biological control agent of Melaleuca quinquenervia. Journal ofInsect Behaviour. 2000. v. 13. (6) p. 915-926. Pemberton, R.W. Predictable risk to native plants in weed biological controOecologia. 2000. v. 125. p. 489-494. Pemberton, R.W., Strong D.R. Safety data crucial for biological control insect agents. Science. 2000. v. 290. p. 1896-1897. Pratt, P.D., Croft, B.A. Banker plants: Release strategies for predatory mites in outdoor landscape nursery systems. Journal of Environmental Horticulture. 2000. v. 18(4). pp. 211-217. Pratt, P.D., Croft, B.A. Overwintering and comparative sampling of Neoseiulfallacis on ornamental nursery plants. Environmental Entomology. 2000. v. 29(5). pp. 1034-1040. Pratt, P.D., Croft, B.A. Screening of predatory mites as potential control agents of pest mites in landscape plant nurseries of the Pacific Northwest.Journal of Environmental Horticulture. 2000. v. 18(4). pp. 218-223. Pratt, P.D., Croft, B.A. Toxicity of pesticides registered for use in landscape nurseries to Acarine biological control agent, Neoseiulus fallaciJournal of Environmental Horticulture. 2000. v. 18(4). pp. 197-201. Rayachhetry, M.B., Pemberton, R.W., Leahy, R., Smith, L. First determinatioof the pathogenicity of Puccinia lygodii on the invasive Japanese climbing fern (Lygodium japonicum). Plant Disease. 2001. v. 85. p. 232. Rayachhetry, M.B., Van, T.K., Center, T.D. Laroche, F.B. Dry weight estimation of the aboveground components of Melaleuca quinquenervia trees isouthern Florida. Forest Ecology and Management. 2001. v. 142. pp. 281-290. Strong, D.R., Pemberton, R.W. Foodwebs, risks of alien enemies and reform obiological control. Wajnberg,E., Scott,J.K., Quimby, P.C., editors. Commonwealth Agricultural Bureau Publishing, Wallingford, Oxon, UK. Evaluating indirect ecological effects of biological control. 2001. p. 57-7 Van, T.K., Rayachhetry, M.B. Center, T.D. Estimating aboveground biomass ofmelaleuca in south Florida. Journal of Aquatic Plant Management. 2000. v. 3pp. 62-67. Walker, S.E., El-Gholl, N.E., Pratt, P.D., Schubert, T.S. First U.S. reportof Pseudocercospora paederiae leaf spot on the invasive exotic Paederia foetida. Plant Disease. 2001. v. 85(2) pp. 232. Wheeler, G.S., Center, T.D. Impact of the biological control agent Hydrellipakistanae (Diptera: Ephydridae) on the submersed aquatic weed Hydrilla verticillata (Hydrocaritaceae). Biological Control. 2001. v. 21. p. 168-181 Wheeler, G. S., Slansky, F. Jr., and Yu, S.J. Food consumption, utilizationand detoxification enzyme activity of larvae of three polyphagous noctuid moth species when fed the botanical insecticide rotenone. Entomologia Experimentalis et Applicata. 2001. v. 98. (2) p. 225-239. Wheeler, G.S., Zahniser, J. Artificial diet and rearing methods for the Melaleuca quinquenervia (Myrtales: Myrtaceae) biological control agent Oxyovitiosa (Coleoptera: Curculionidae). Florida Entomologist. 2001. v. 88. (3p. 449-451. Wineriter, S.A., Buckingham, G.R., Frank, J.H. Host range testing of the psyllid, Boreioglycaspis melaleucae (Homoptera: Psyllidae), for control of Melaleuca quinquenervia (Myrtales: Myrtaceae). Spencer, N.R., editor. Proceedings X International Symposium on Biological Control of Weeds, July 4-14, 1999. 2000. p. 431-432. Hill, M. P., Center, T.D., Stanley, J.N., H. Cordo, A., Coetzee, J., Byrne,M.J. The performance of the water hyacinth mired, Eccritotarsus catarinension water hyacinth and pickerelweed: a comparison of laboratory and field results. Pp. 357-366. In: N. R Spencer (editor), Proceedings of the X International Symposium on Biological Control of Weeds, 4-14 July 1999, Montana State University, Bozeman, Montana. 2000.