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Air potato, Dioscorea bulbifera L. (Dioscoreaceae), is an invasive vine that climbs into vegetation outcompeting native species and altering ecosystems in the southeastern USA. The biological control agent, Lilioceris cheni Gressitt and Kimoto (Coleoptera: Chrysomelidae), has been released in Florida since 2011 and in other states including Georgia (2015), Louisiana (2016), Texas (2017), Mississippi (2018), and Alabama (2018) to manage air potato. Despite the wide distribution of the weed and mass rearing efforts, there are no studies documenting the establishment of L. cheni outside of Florida. The objectives of this study were to document the beetle release efforts by several agencies and determine the establishment and impact of L. cheni across the southeastern USA. Using community science reports and field surveys, we documented the distribution of air potato and L. cheni. Results demonstrated that the distribution of air potato extends to temperate regions from South Carolina and Georgia to subtropical regions of Louisiana, Texas, and Florida. Surveys showed that the beetle is present across all states with releases, and numbers fluctuated between 6 and 37 beetles counted per 30-surveyor-minutes. Most sites sampled had moderate to high beetle damage (scales of 3–4 out of 5), and air potato cover was low to moderate (2–3 out of 5). However, air potato was still abundant in some areas, which suggests the need for additional beetle releases and/or the use of other tactics to achieve management goals. [ABSTRACT FROM AUTHOR]

Southern University offers summer programs, mentorships and training, and recruitment events for high school students. Although engagement with high school students is essential, I think it is imperative to also reach students earlier in their K-12 science education, particularly in public schools with less access to resources. As a new assistant professor and the only entomologist in the college, I was excited about the challenge of establishing a new program at Southern University in Baton Rouge, Louisiana. [Extracted from the article]

Brazilian peppertree,Schinus terebinthifoliaRaddi (Anacardiaceae), is a South American plant that is highly invasive in Florida. The impact of insect herbivores on the performance of Brazilian peppertree was evaluated at two locations in Florida using an insecticide exclusion method. Although 38 species of insect herbivores were collected on the invasive tree, there were no differences in growth or reproductive output of insecticide protected and unprotected trees, providing evidence that insect feeding had no measurable impact on tree performance. The majority of insects collected on Brazilian peppertree were generalists, and several were serious agricultural pests. [ABSTRACT FROM PUBLISHER]

Brazilian peppertree, Schinus terebinthifolia Raddi ( Anacardiaceae), is an invasive weed of natural and agricultural areas of Florida, Hawaii, and Texas ( USA). Biological control presents an environmentally safe and cost-effective control method for invasive populations of this weed. Though many potential agents have been tested for specificity, nearly all have been rejected due to a broad host range. However, one species, a thrips Pseudophilothrips ichini ( Hood) ( Thysanoptera: Phlaeothripidae), shows promise from field observations and quarantine host range tests. A series of no-choice, choice, and multiple-generation tests was conducted on 127 plant taxa (including five mango and four pistachio varieties) from 45 families and 33 orders. In no-choice starvation tests, the thrips fed and produced offspring on the target weed (124 F1 adults per plant), whereas no or few (<4 F1 adults per plant) were obtained on non-target species. The primary exception was another exotic invasive tree Schinus molle L., on which an average 20 F1 thrips adults were produced. No-choice tests indicated that small numbers of F1 offspring were produced on nine other non-target plant species. The numbers of F1 offspring produced on these plants were <3% of those produced on the target weed. In choice tests, on average two or fewer F1 adults were produced on four non-target species tested, compared with 64 F1 adults on the target weed. Multiple-generation tests indicated that three generations of thrips were maintained only on the target weed and S. molle with no differences between these two plant species or across generations. Thus, this thrips species has a narrow host range that includes the two invasive Schinus spp. tested here. If released, the thrips P. ichini will constitute safe and potentially effective biological control of Brazilian peppertree in North America and Hawaii. [ABSTRACT FROM AUTHOR]

Brazilian peppertree,Schinus terebinthifoliaRaddi (Sapindales: Anacardiaceae) (hereafterSchinus), is one of the worst invasive species in Florida and Hawaii. The thripsPseudophilothrips ichiniHood (Thysanoptera: Phlaeothripidae) is being considered as a potential biological control agent ofSchinus. 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 byP. ichiniwere 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 ofP. ichinimay establish in similar areas of the USA, overlapping with the distribution ofSchinus. 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 FloridaSchinushaplotypes, 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 thatSchinusgrowth was greatly reduced by thrips feeding, which may result in lower weed reproduction and densities in the field. [ABSTRACT FROM PUBLISHER]

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 latiforcepsBurckhardt (Hemiptera: Calophyidae), was recently discovered in the state of Bahia, Brazil. Leaf feeding by the nymphs ofC. latiforcepsstimulates 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 ofC. latiforcepsunder 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 byC. latiforcepsresulted 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. latiforcepsappears to have characteristics of a promising candidate for biological control of Brazilian peppertree. [ABSTRACT FROM PUBLISHER]

The cycad aulacaspis scale (CAS),Aulacaspis yasumatsuiTakagi (Hemiptera: Diaspididae), is a serious pest of ornamental cycads in the southeastern United States. In Florida, CAS was first reported in Miami in 1996 and is now present in 43 Florida counties. Chemical control of CAS can be effective, but it is expensive, and insecticides must be frequently and regularly applied. Recent surveys of natural enemies in Thailand identified a new potential biological control agent of CAS. The objective of this study was to examine the temperature requirements and consumption rates ofPhaenochilus kashayaGiorgi and Vandenberg (Coleoptera: Coccinellidae). Survival, developmental time and number of scales consumed byP.kashayawere measured at four constant temperatures (20, 25, 30 and 35°C). In addition, adult longevity and consumption were recorded at three constant temperatures (20, 25 and 30°C).Phaenochilus kashayacompleted development to adulthood at temperatures ranging from 20 to 30°C. The highest survival rate (48%) was obtained at 25°C, and the accumulated degree-days for this species was 714.Phaenochilus kashayais a voracious predator of CAS, consuming 380 scales during the larval stage and an estimated 4700 scales during the adult stage. Adult longevity varied from 59 days at 30°C to 220 days at 20°C for females, and 31 days at 30°C to 148 days at 20°C for males. The intrinsic rate of increase (rm) was 0.34 at 20°C, which is high compared with other coccinellid species. According to this study,P. kashayahas the potential to be an effective biological control agent of the CAS in Florida. [ABSTRACT FROM AUTHOR]

Rising atmospheric CO2 levels could have drastic effects on the performance of invasive weeds and their insect herbivores. Despite the importance of biological control as an effective management tool for environmental weeds, there have been few studies on the potential impact of climate change on the future efficacy of biological control. The objective of the present study was to evaluate the effect of elevated CO2 on the performance of tropical soda apple Solanum viarum (Solanaceae) and its biological control agent Gratiana boliviana (Coleoptera: Chrysomelidae). We established three levels of CO2 in environmental growth chambers: ambient (400 ppm), medium (580 ppm) and high (780 ppm). Plants growing at the high level had greater biomass compared to those growing at the ambient and medium levels of CO2. Leaf water content and the amount of leaf nitrogen were reduced at high compared to ambient or medium CO2 levels. G. boliviana immature survival and developmental time were negatively affected at high CO2 but not at medium or ambient levels. Adults were lighter and smaller when reared at the high CO2 level compared to ambient and medium treatments, while adult fecundity was higher at the medium CO2 level. Leaf area consumed by fifth instars was lower when feeding on plants grown at the high CO2 level either inside a Petri dish or on potted plants. These results suggest that beetle performance may be diminished under future climate. However, further studies should incorporate other factors such as temperature and precipitation as well as the evolutionary potential of herbivores and plants to adapt to a changing climate. [ABSTRACT FROM AUTHOR]

Brazilian peppertree, Schinus terebinthifolius Raddi (Anacardiaceae), native to South America, has invaded different habitats throughout south and central Florida. In recent surveys of natural enemies conducted in Salvador, Brazil (native range), a new species in the genus Paectes (Lepidoptera: Euteliidae) was found feeding on foliage of Brazilian peppertree. The objectives of this study were to describe the adult, larva and pupa and to examine the life history parameters of the new species, Paectes longiformis Pogue, a potential biocontrol agent of Brazilian peppertree. Survival and development of immature stages were examined at six constant temperatures (ranging from 16 to 34°C). All stages of P. longiformis were exposed to 0°C for 0.5, 1, 2, 4 and 8 d, and lethal times were calculated (Ltime50, Ltime90). Paectes longiformis laid eggs singly on the plant foliage and completed five instars including a non-feeding pre-pupal stage that moved to the soil where it spun a cocoon. Complete development occurred at temperatures from 19 to 31°C, the lower developmental threshold was estimated to be 11.5°C and 454 degree-days were required to complete development from egg to adult. The lethal times at 0°C (Ltime50=1 d, Ltime90=5 d) were used to construct isothermal lines to predict areas of establishment in the continental US. The predicted distribution includes the southeastern states including Florida, in addition to southern Texas and Arizona, and California. Overall, this study provides a species description, along with baseline information about the biology and temperature requirements of P. longiformis, a potential biological control agent of Brazilian peppertree. [ABSTRACT FROM PUBLISHER]

Schinus terebinthifolius Raddi (Anacardiaceae) is an introduced tree from South America that has invaded many ecosystems throughout central and south Florida, USA. Exploratory surveys in the plant’s native range identified several potential biocontrol agents, including the leaflet rolling moth, Episimus unguiculus Clarke (Lepidoptera: Tortricidae). The larval stages of E. unguiculus tie together the plant leaflets while feeding and can completely defoliate small plants. The native love vine, Cassytha filiformis L. (Lauraceae), has been found parasitizing S. terebinthifolius in Florida. Natural processes such as plant parasitism may be one of the components of an integrated approach for S. terebinthifolius management in Florida. Thus, the objective of this study was to evaluate the combined effects of insect herbivory and plant parasitism on the performance of S. terebinthifolius. A factorial design experiment was conducted in the greenhouse to determine the effect of C. filiformis parasitism and E. unguiculus feeding damage on the growth and biomass of S. terebinthifolius. Results showed that plant parameters, including leaflet biomass, growth rate, and flower production, were negatively affected by plant parasitism and insect herbivory. Moreover, the decrease in S. terebinthifolius performance was greater when these two factors were combined, indicative of a synergistic relationship. In addition, the combined effect of C. filiformis and E. unguiculus suppressed plant performance for at least 2 months after the moths were removed. Therefore, increased control of S. terebinthifolius stands may be achieved in those areas where C. filiformis is present in Florida (e.g., pinelands, hammock forests) if the biocontrol agent E. unguiculus is approved for release. [ABSTRACT FROM AUTHOR]