Comparison of two populations of Pseudophilothrips ichini (Thysanoptera: Phlaeothripidae) as candidates for biological control of the invasive weed Schinus terebinthifolia (Sapindales: Anacardiaceae)

Brazilian peppertree, Schinus terebinthifolia Raddi (Sapindales: Anacardiaceae) (hereafter Schinus), is one of the worst invasive species in Florida and Hawaii. The thrips Pseudophilothrips ichini Hood (Thysanoptera: Phlaeothripidae) is being considered as a potential biological control agent of Schinus. Two populations of this thrips were collected in the weed's native range; one from central-east Brazil (Ouro Preto thrips) and a second from north-east Brazil (Salvador thrips). Temperature requirements, adult fecundity and impact on different plant haplotypes by P. ichini were examined in the laboratory. Complete development of thrips from both populations occurred at temperatures ranging from 20 to 30°C. Two approaches were used to model the predicted distributions of the thrips populations in the USA: the physiological model (NAPPFAST) based on cold tolerance and the ecological niche model based on climatic variables (MaxEnt). The physiological model predicted that both populations of P. ichini may establish in similar areas of the USA, overlapping with the distribution of Schinus. However, the niche model predicted that only the Ouro Preto thrips could establish in the USA. The difference in model predictions suggests an apparent preadaptation of the Salvador thrips to lower temperatures than those experienced at the locations they were collected in Brazil. The Ouro Preto thrips had similar fecundity on two Florida Schinus haplotypes, whereas lower fecundity on haplotype A was found for the Salvador thrips. Based on these results, the Ouro Preto population may be better adapted to the climatic conditions and plant haplotypes found in Florida. Moreover, greenhouse studies indicated that Schinus growth was greatly reduced by thrips feeding, which may result in lower weed reproduction and densities in the field.     

Life history and host range of the leaf blotcher Eucosmophora schinusivora: a candidate for biological control of Schinus terebinthifolius in the USA

The host range of Eucosmophora schinusivora Davis and Wheeler (Lepidoptera: Gracillariidae) was studied to assess its suitability as a biological control agent of Schinus terebinthifolius Raddi (Anacardiaceae), a serious environmental and agricultural weed in the USA and elsewhere in the world. The life history of this insect species and its host range were determined in the laboratory with adult no-choice oviposition and larval development tests. This species has five instars, the first three are sap-feeding miners and the last two are tissue feeding. Total development time was 31.7 days. To examine specificity of this species, 10 plant species in Anacardiaceae were selected based on taxonomic relatedness to S. terebinthifolius, economic importance, and availability. In the laboratory, except for Anacardium occidentale and Cotinus obovatus, all of the tested species were accepted for oviposition with a marked preference for the weed S. terebinthifolius, Schinus molle, Rhus copallinum, Rhus sandwicensis and Pistacia chinensis. Complete development, from egg to adult, was achieved only on S. terebinthifolius, S. molle, R. copallinum, P. chinensis and Metopium toxiferum. In conclusion, E. schinusivora will not be considered for the biological control of S. terebinthifolius in the continental USA. However, the utilisation of this species in other infested areas such as Hawai'i and Australia should be considered.     

Risk assessment of Episimus unguiculus (Lepidoptera: Tortricidae), a biological control agent of Schinus terebinthifolia (Sapindales: Anacardiaceae) in Hawaii,USA

Schinus terebinthifolia Raddi (Anacardiaceae) is an introduced ornamental tree from South America that has become one of the most invasive weeds in Hawaii and Florida, USA. Exploratory surveys in the plant’s native range from 1950 to 2014 identified several potential biological control agents. One of these is the leaflet rolling moth Episimus unguiculus Clarke (Lepidoptera: Tortricidae), previously known as Episimus utilis Zimmerman. This biological control agent was released in Hawaii in the 1950s where high densities were occasionally observed, leading to partial control of S. terebinthifolia by the 1960s. Larvae are leaf tiers capable of completely defoliating small plants. In order to investigate the release of E. unguiculus in the continental USA, a series of laboratory no- choice, and multiple-choice tests were conducted in Florida, and a preliminary open field test with a native plant in Hawaii. Under the confined laboratory conditions imposed during the no-choice tests, E. unguiculus accepted the economically important Pistacia spp. and several other non-target plants for oviposition and development. However, in the multiple-choice tests E. unguiculus exhibited a clear preference for S. terebinthifolia relative to non-target plants accepted in the no-choice tests. Overall, the results of field observations during surveys in South America and Hawaii and host range studies completed in Hawaii and Florida showed that E. unguiculus is a narrow specialist on S. terebinthifolia, its natural host plant.     

The leafmining Leurocephala schinusae (Lepidoptera: Gracillariidae): not suitable for the biological control of Schinus terebinthifolius (Sapindales: Anacardiaceae) in continental USA

The host range of Leurocephala schinusae Davis & Mc Kay (Lepidoptera: Gracillariidae) was studied to assess its suitability as a biological control agent of Schinus terebinthifolius Raddi (Anacardiaceae), a serious environmental weed in the USA and elsewhere in the world. The host range was determined in the laboratory with adult no-choice oviposition (Argentina and USA) and larval development tests (USA). Seventeen plant species in ten genera were selected based on taxonomic relatedness to S. terebinthifolius, economic importance, and availability. Additional information was obtained by sampling foliage of S. terebinthifolius and six other South American native Anacardiaceae species in north-eastern Argentina. In the laboratory, except for Lithrea molleoides and Spondias mombin, all of the tested species were accepted for oviposition with a marked preference for Rhus aromatica. Incipient mines successfully developed into complete mines, pupae and adults on R. aromatica, Rhus copallinum, Schinus molle, Schinus lentiscifolius and S. terebinthifolius. In the field, although L. schinusae showed a clear preference for S. terebinthifolius, the host range, as determined by samples of host use in the native range, included three other Schinus species (S. lentiscifolius, Schinus longifolius, Schinus weinmannifolius) and one Astronium species (Astronium balansae). In conclusion, L. schinusae will not be considered for the biological control of S. terebinthifolius in continental US. However, the utilisation of this species in other infested areas such as Hawaii and Australia should be further discussed.     

Host range testing and life history of the defoliator Hymenomima nr. memor: an unsuitable biological control agent for Schinus terebinthifolia in the U.S.A.

Host range of larvae of Hymenomima nr. memor (Lepidoptera: Geometridae) was examined in quarantine to evaluate its suitability as a biological control of Brazilian peppertree, Schinus terebinthifolia. Brazilian peppertree, S. terebinthifolia is an environmental and agricultural weed from South America that had invaded many subtropical and tropical areas of the world including Florida and Hawaii, USA. Laboratory life history and quarantine host range studies of H. memor were conducted with no-choice feeding tests. These tests included eight species of the Anacardiaceae and one species of Sapindaceae. Larvae of H. memor had five to six instars with each head capsule width increasing by 1.68-X. Development time from neonate to adult was 46.7?±?2.2 days. In host range tests, neonates completed development to the adult stage on all non-target species, except Toxicodendron radicans. Moreover, developmental times were delayed and pupal weights were reduced for larvae fed Spondias purpurea leaves. Due to the broad host range exhibited by H. memor larvae, this species will not be considered as a biological control agent of S. terebinthifolia in the continental U.S.A.     

Gallerucida bifasciata (Coleoptera: Chrysomelidae), a potential biological control agent for Japanese knotweed (Fallopia japonica)

Host specificity of foreign natural enemies are becoming more and more critical in classical biological control programs, as concerns about potential risk from introduced biocontrol agents have been increasing recently. Understanding the insect's fundamental and ecological host ranges is the first step in determining the potential for introduction of an insect to control invasive plants. Japanese knotweed, Fallopia japonica (Houttuyn) Ronse Decraene (Polygonaceae) is an invasive weed in the United States and Europe. A leaf beetle, Gallerucida bifasciata (Coleoptera: Chrysomelidae) is an important natural enemy attacking this plant in Asia. However, its host range records were ambiguous. This study examined the beetle's host specificity through a set of choice and no-choice tests in the laboratory and field in its native China. Gallerucida bifasciata larvae were able to complete development on seven of 87 plant species in larval development tests, while adults fed and oviposited on 10 plants in no-choice tests. Multiple choice tests showed adults strongly preferred Fallopia japonica, Persicaria perfoliata (L.) H. Gross and Polygonum multiflorum Thunb over all other plants. Open field tests and field surveys further revealed that these three species were in its ecological host range. The results of this study suggest that G. bifasciata is a potential promising agent for control of Japanese knotweed in the United States and Europe, although additional host specificity tests and risk assessment should be completed.     

Seasonal activity,habitat preferences and larval mortality of the leaf-mining fly Calycomyza eupatorivora (Agromyzidae), a biological control agent established on Chromolaena odorata (Asteraceae) in South Africa

The leaf-mining fly Calycomyza eupatorivora Spencer (Diptera: Agromyzidae) has become widely established in the eastern regions of South Africa, following its release for the biological control of the invasive shrub Chromolaena odorata (L.) King and Robinson. This study was conducted to gain some insight into the impact of C. eupatorivora populations, by assessing their seasonal activity, habitat preferences, levels of leaf exploitation and extent of larval mortality in the field over a 1-year period. Leaf mining intensity was poorly synchronised with leaf availability, with leaf exploitation peaking at the end of the growing season of C. odorata. Although significantly more mines were recovered on plants growing in shaded situations, the percentage of available leaves that were exploited for mining was not significantly different between plants growing in shaded versus open situations. Overall, the levels of leaf damage were trivial with mines recovered from <5% of available leaves that were sampled during the study. Besides leaf-quality requirements, these low levels of leaf exploitation may have been influenced by high larval mortality which varied between 60 and 83%, depending on whether lower or higher estimates were used. These evaluations have verified the results of earlier laboratory studies which suggested that the impact of C. eupatorivora on mature populations of C. odorata in South Africa will be negligible.     

Release and distribution of Lilioceris cheni (Coleoptera: Chrysomelidae), a biological control agent of air potato (Dioscorea bulbifera: Dioscoreaceae), in Florida

From 2012 to 2015, 429,668 Lilioceris cheni Gressit and Kimoto (Coleoptera: Chrysomelidae) were released in Florida for biological control of air potato Dioscorea bulbifera L. (Dioscoreaceae). In the fall of 2015, a state-wide survey was conducted at 113 randomly selected air potato infestations in order to determine the spatial distribution of L. cheni. Damage due to L. cheni was found at 86% of locations and was low in the Florida panhandle where air potato was relatively uncommon and fewer beetles had been released, and in far south Florida, despite high numbers of beetle releases. On average, beetles travelled 9.5?km from the nearest release site to survey sites from the date of release to the time of the survey, with a maximum distance of nearly 67?km. The rate of spread was estimated at 8.2?km/year under the assumption that beetles present at survey sites migrated or were moved from the nearest release site. Air potato vines produced fewer aerial tubers, the vegetative propagule of air potato, as foliar damage due to L. cheni increased. The results suggest that future research efforts should focus on determining the biotic and abiotic factors that may be limiting establishment in some areas of Florida.     

Host plant oviposition preference of Ceratapion basicorne (Coleoptera: Apionidae), a potential biological control agent of yellow starthistle

Ceratapion basicorne is a weevil native to Europe and western Asia that is being evaluated as a prospective classical biological control agent of Centaurea solstitialis (yellow starthistle) in the United States. Choice oviposition experiments were conducted under laboratory conditions to help assess host-plant specificity of the insect. Mean oviposition rates were highest on C. solstitialis (66% of eggs, on a per replicate basis) followed by Centaurea cyanus (bachelor's button 22%), Centaurea melitensis (6%), Centaurea americana (1%), Saussurea americana (3%) and Carthamus tinctorius (safflower 2%). Adult feeding damage followed a similar pattern; however, there was less oviposition relative to the amount of adult feeding on each of the non-target species than on the target host plant, C. solstitialis. Thirteen safflower varieties were tested, and oviposition occurred on eight of them, at low rates. Adult feeding occurred on all safflower varieties tested, although at rates much lower than on yellow starthistle. The results were intermediate between those of previously reported no-choice laboratory and open field experiments. Overall, the combined results support the hypothesis that C. basicorne is not likely to attack any of the non-target plant species tested here except possibly C. cyanus and C. melitensis, which are both invasive alien plants.     

Biology, host specificity tests, and risk assessment of the sawfly Heteroperreyia hubrichi, a potential biological control agent of Schinus terebinthifolius in Hawaii

Heteroperreyia hubrichiMalaise (Hymenoptera: Pergidae), a foliagefeeding sawfly of Schinusterebinthifolius Raddi (Sapindales:Anacardiaceae), was studied to assess itssuitability as a classical biological controlagent of this invasive weed in Hawaii. No-choice host-specificity tests were conductedin Hawaiian quarantine on 20 plant species in10 families. Besides the target weed, adultfemales oviposited on four test species. Females accepted the Hawaiian native Rhussandwicensis A. Gray (Sapindales:Anacardiaceae) as an oviposition host equallyas well as the target species. The other threespecies received significantly fewer eggs. Neonate larvae transferred onto test plantssuccessfully developed to pupae on S.terebinthifolius (70% survival) and R.sandwicensis (1% survival). All other 18test plant species failed to support larvaldevelopment. A risk analysis was conducted toquantify the acceptability of non-targetspecies as host plants for H. hubrichi onthe basis of the insect's performance atvarious stages in its life cycle. Risk ofdamage to all plant species tested wasinsignificant except for R. sandwicensis. Risk to this native plant relative to S.terebinthifolius was estimated at 1%. Currently this level of risk is too high torequest introduction of this insect into theHawaiian environment. Detailed impact studiesin the native range of S. terebinthifoliusare needed to identify thepotential benefit that this insect offers. Also, field studies in South America withpotted R. sandwicensis would give a morereliable analysis of the risk this nativeHawaiian plant would face from naturalpopulations of H. hubrichi.     

Native range density,host utilisation and life history of Calophya latiforceps (Hemiptera: Calophyidae): an herbivore of Brazilian Peppertree (Schinus terebinthifolia)

Native range and life history studies of an agent provide critical information during the early stages of a weed biological control programme. Brazilian peppertree is considered to be one of the worst invasive trees of Florida uplands because of negative environmental impacts and lack of effective long-term control methods. A potential biological control agent of Brazilian peppertree, Calophya latiforceps Burckhardt (Hemiptera: Calophyidae), was recently discovered in the state of Bahia, Brazil. Leaf feeding by the nymphs of C. latiforceps stimulates the tree to form pit galls. The objectives of this study were to quantify gall densities in Bahia and to study the life history adaptations of C. latiforceps under greenhouse conditions. Densities of galls and their mortality sources were recorded in August 2012 and March 2013 from trees located along linear transects. Gall density per leaf ranged from 1.6 to 37.5 and 0.3 to 12.8, in August and March, respectively. Nymphal mortality due to parasitism and entomopathogens ranged from 1.2 to 13.8%. Greenhouse observations of host colonisation and evaluations of immature survival and adult performance were conducted using plants from Bahia. A critical step for host colonisation was gall initiation in response to nymphal feeding. Herbivory by C. latiforceps resulted in stunted growth, leaf deformation, yellowing and shedding of leaves. Immature survival and development time were influenced by tree, and ranged from 11 to 75% (average 40%), and 35 to 53 days (average 38.6 days), respectively. Adults lived in average for 9.3 ± 0.6 days; and females laid 85.8 ± 16.4 eggs. C. latiforceps appears to have characteristics of a promising candidate for biological control of Brazilian peppertree.     

Evaluation of Cyphocleonus trisulcatus (Coleoptera: Curculionidae) as a potential biological control agent for Leucanthemum vulgare in North America

Leucanthemum vulgare, a perennial forb native to Eurasia, has become invasive in several other parts of the world. Since there is a lack of methods suitable for sustainable management of this plant across invaded landscapes, a biological control project has been initiated in North America and Australia. We evaluated the potential of the root-feeding weevil Cyphocleonus trisulcatus as a biological control agent for L. vulgare in North America by investigating its impact on L. vulgare and studying its larval host range under no-choice, multiple-choice cage and open-field conditions. Our impact experiment revealed that larval feeding by C. trisulcatus can severely damage and even kill plants. No-choice tests conducted with 41 non-target species showed that C. trisulcatus can develop on five closely related species. In a multiple-choice cage test established with three of these species, the medicinal plant Matricaria chamomilla and the native North American M. occidentalis were also attacked, but to a lower degree than L. vulgare. An open-field test conducted with four varieties of the ornamental Shasta daisy (Leucanthemum × superbum and L. × maximum) revealed similar attack on Shasta daisy as on L. vulgare. Due to the popularity of Shasta daisies, we suggest that C. trisulcatus, despite its potential to suppress L. vulgare populations, is not a suitable biological control agent for North America. However, C. trisulcatus may still be a potential biological control agent for L. vulgare in regions where Shasta daisy is less popular, such as Australia. Further host-range tests with species native to Australia as well as with additional species important for the horticultural industry in Australia are currently under way.     

Biology and field host range of Ceutorhynchus cardariae,a potential biological control agent for Lepidium draba

Lepidium draba (Brassicaceae) is a clonal herb, originating from Eurasia, which is invasive in North America. A classical biological control project was initiated in 2001, and the gall‐forming weevil Ceutorhynchus cardariae was prioritized as a candidate agent. We studied its biology and field host range between 2003 and 2014 in the laboratory and a common garden in Switzerland and in the field in Romania. Ceutorhynchus cardariae is a univoltine to bivoltine species. In Switzerland, oviposition usually started at the beginning of March and can occur at temperatures as low as 2.5°C. Galls are formed on stems, leaf stalks and midribs of L. draba rosettes and bolting plants. Gall size increased with an increasing number of larvae per gall. The three larval instars feed inside the galls and leave the plant to pupate in the soil once mature. In Switzerland, development from egg to adult took about 12 weeks in spring. Adults emerged from May to July. After a brief feeding period, adults aestivate. From late summer, feeding recommenced and females may oviposit, forming a partial second generation. Eggs and all larval instars can be found in galls throughout winter. The rate of larval ectoparasitism reached 78%, while endoparasitism was low with a maximum of 2.3%. Lepidium draba populations differed in their suitability for development (number of C. cardariae produced), indicating that effectiveness of C. cardariae – in case released – may be variable. In the field, we observed that gall formation by C. cardariae can severely stunt or even kill shoots. Investigations on the field host range of C. cardariae indicated that only the closely related Lepidium campestre may act as an alternative host for the weevil in Europe. Host‐specificity tests are underway to determine its environmental safety before field release in North America is being considered.     

Biological Control as a Tool for Ecosystem Management

Biological control is proposed as a tool useful for ecosystem management and compatible with the goals of often competing interests regarding the restoration and maintenance of ecosystems. We summarize the effects of introduced species on ecosystems in three broad groups: insects, vertebrates, and weeds. We then discuss the role of biological control for each of these groups in the context of ecosystem management and realistic outcomes. Of the three groups, we show that biological control of weeds appears to have the best chance for success in ecosystem management. We provide two case studies to support our ideas and finally discuss future needs and trends including fiscal considerations, cost/benefits associated with biological weed control, and potential funding sources.     

Chloroplast and microsatellite DNA diversities reveal the introduction history of Brazilian peppertree (Schinus terebinthifolius) in Florida

Brazilian peppertree (Schinus terebinthifolius) is a woody perennial that has invaded much of Florida. This native of northeastern Argentina, Paraguay, and Brazil was brought as an ornamental to both the west and east coasts of Florida at the end of the 19th century. It was recorded as an invader of natural areas in the 1950s, and has since extended its range to cover over 280 000 ha. Our goals were to understand the history of this invasion, as one step toward understanding why this exotic was so successful, and ultimately to improve development of biological control agents. We sampled plants from the native and exotic ranges, particularly Florida, and genotyped these individuals at nuclear and chloroplast loci. Nuclear microsatellite and cpDNA loci reveal strong genetic population structure consistent with limited dispersal in the introduced and native ranges. Bayesian clustering of microsatellite data separates the east and west coast plants in Florida into distinct populations. The two chloroplast haplotypes found in Florida are also concordant with this separation: one predominates on the east coast, the other on the west coast. Analysis of samples collected in South America shows that haplotypes as distinct as the two in Florida are unlikely to have come from a single source population. We conclude that the genetic evidence supports two introductions of Brazilian peppertree into Florida and extensive hybridization between them. The west coast genotype likely came from coastal Brazil at about 27 degrees south, whereas the east coast genotype probably originated from another, as yet unidentified site. As a result of hybridization, the Florida population does not exhibit low genetic variation compared to populations in the native range, possibly increasing its ability to adapt to novel environments. Hybridization also has important consequences for the selection of biocontrol agents since it will not be possible to identify closely co-adapted natural enemies in the native range, necessitating more extensive host testing.     

Selection of promising fungal biological control agent of the western flower thrips Frankliniella occidentalis (Pergande)

Aims: Larval stages of Frankliniella occidentalis are known to be refractory to fungal infection compared with the adult stage. The objective of this study was to identify promising fungal isolate(s) for the control of larval stages of F. occidentalis. Methods and Results: Ten isolates of Metarhizium anisopliae and eight of Beauveria bassiana were screened for virulence against second‐instar larvae of F. occidentalis. Conidial production and genetic polymorphism were also investigated. Metarhizium anisopliae isolates ICIPE 7, ICIPE 20, ICIPE 69 and ICIPE 665 had the shortest LT₅₀ values of 8·0–8·9 days. ICIPE 69, ICIPE 7 and ICIPE 20 had the lowest LC₅₀ values of 1·1 × 10⁷, 2·0 × 10⁷ and 3·0 × 10⁷ conidia ml^?1, respectively. Metarhizium anisopliae isolate ICIPE 69 produced significantly more conidia than M. anisopliae isolates ICIPE 7 and ICIPE 20. Internally transcribed spacers sequences alignment showed differences in nucleotides composition, which can partly explain differences in virulence. Conclusion: These results coupled with the previous ones on virulence and field efficacy against other species of thrips make M. anisopliae isolate ICIPE 69 a good candidate. Significance and Impact of the Study: Metarhizium anisopliae isolate ICIPE 69 can be suggested for development as fungus‐based biopesticide for thrips management.     

Potential of Haplothrips brevitubus (Karny) (Thysanoptera: Phlaeothripidae) as a predator of mulberry thrips Pseudodendrothrips mori (Niwa) (Thysanoptera: Thripidae)

The predation potential of Haplothrips brevitubus (Karny) for thrips was evaluated in the laboratory. When second stage larvae of Pseudodendrothrips mori (Niwa) were presented to an adult H. brevitubus at densities of 10, 20, 30, and 40 larvae per cage at 25 °C over 24 h, the number of larvae consumed per day increased with an increasing density up to 30. Predation of H. brevitubus exhibited the type II functional response. The mean development time of the egg, larva, and pupa of H. brevitubus were 4.5, 9.6, and 4.8 days, respectively, at 25 °C. The survival rate from egg to adult emergence was 94.7%. One H. brevitubus larva consumed 41.6 P. mori larvae on average during the total larval period. Adult longevity was 35.2 days in females and 34.6 days in males. The pre-oviposition period was 2.7 days and the oviposition period was 31.5 days. The lifetime fecundity was 120.1 eggs and the mean daily oviposition rate was 3.6 eggs. Calculated mean generation time (T) was 29.5 days, intrinsic rate of natural increase (r_m) was 0.162, and net reproductive rate (R₀) was 56.5. The r_m value of H. brevitubus was higher than that of Thrips palmi Karny and almost equal to that of Frankliniella occidentalis (Pergande). These results indicate that H. brevitubus has good potential as a predator of P. mori and is likely to be useful for controlling thrips.     

Laboratory biology and impact of a stem-boring weevil Apocnemidophorus pipitzi (Coleoptera: Curculionidae) on Schinus terebinthifolia

Brazilian peppertree, Schinus terebinthifolia Raddi (Anacardiaceae), was introduced into Florida, USA, from South America as an ornamental plant in the late 19th and early 20th centuries. It eventually escaped cultivation and is a serious threat to the state’s biodiversity. In the 1980s, this invasive weed was targeted for classical biocontrol. Surveys for natural enemies of Brazilian peppertree conducted in the native range resulted in the discovery of several candidate biocontrol agents. A stem-boring weevil identified as Apocnemidophorus pipitzi (Faust) was collected in Paraguay and transported under permit to Florida, USA. A laboratory colony of A. pipitzi was established in April 2007 by caging adults on cut branches of Brazilian peppertree supplemented with leaf bouquets. Adults are defoliators that feed mainly on the upper surface of subterminal leaflets. Females deposit eggs singly inside the stems and larvae feed under the bark where they damage the vascular cambium. There are five instars, pupation occurs inside the stem and a new generation is produced in 3–4 months. Growth of potted plants with and without exposure to weevil herbivory was compared over an 11-month period. Feeding damage by adults and larvae significantly increased leaf abscission and reduced leaf and root biomass accumulation.     

Non-target plant testing of the flea beetle Agasicles hygrophila,a biological control agent for Alternanthera philoxeroides (alligatorweed) in China

Non-target plant selection tests using 20 representative species showed that Agasicles hygrophila could feed on Alternanthera sessilis, but the mature larvae did not pupate successfully. A. hygrophila could not complete their life cycle on the other plant species tested. Thus, A. hygrophila is safe for controlling Alternanthera philoxeroides in China.