Norman Carey Leppla

Prof. Norman Carey Leppla

Institute of Food and Agricultural Sciences, University of Florida, Gainesville, FL 32611, USA
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Research Focus & Metrics

Academic Career Length

21Years (2006-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 July 2019 in Journal of Insect Science
Verified
Journal Article
Open access
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YMYasaman Moghaddassi
Yasaman Moghaddassi
AAAhmad Ashouri
Ahmad Ashouri
ABAli R. Bandani
Ali R. Bandani
Norman Carey LepplaNorman Carey Leppla
Norman Carey Leppla
PSPaul D Shirk
Paul D Shirk
Trichogramma spp., among the most common parasitoids used for augmentation biological control, often are mass-reared on eggs of the Mediterranean flour moth, Ephestia kuehniella (Zeller). To evaluate removal of nutritional components from the E. kuehniella larval diet and reduce production costs, colonies were maintained using one of three diets: a standard diet consisting of eight ingredients, a reduced diet containing whole wheat flour, glycerol, and Brewer’s yeast, or a third minimal diet of only whole wheat flour. The standard diet sustained the fastest larval development, female pupae with the greatest mass, the highest level of adult emergence, and production of the most eggs per female. Eggs from moths reared as larvae on the standard or reduced diet had equivalent mass, length, and percent hatch. Females from larvae fed the minimal diet produced eggs with the least mass that were shorter and had the lowest percent hatch. Eggs from the three E. kuehniella colonies were exposed separately to Trichogramma brassicae Bezdenko females to determine their acceptance for oviposition. More of the eggs from the standard diet were parasitized by the females, eggs from the reduced and minimal diets being less acceptable. The percent emergence of the parasitoids was the same regardless of diet; however, the largest wasps emerged from the standard diet eggs and a greater proportion of them were females. Consequently, the standard E. kuehniella larval diet resulted in the highest rate of reproduction and robust eggs that produced superior T. brassicae wasps.

4 September 2016 in Journal of Economic Entomology
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Journal Article
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ASA. M. Szyniszewska
A. M. Szyniszewska
Norman Carey LepplaNorman Carey Leppla
Norman Carey Leppla
ZHZ. Huang
Z. Huang
ATAndrew Tatem
Andrew Tatem
The Mediterranean fruit fly, Ceratitis capitata (Wiedemann), is one of the most economically damaging pests in the world and has repeatedly invaded two major agricultural states in the United States, Florida and California, each time requiring costly eradication. The Mediterranean fruit fly gains entry primarily in infested fruit carried by airline passengers and, since Florida and California each receive about 13 million international passengers annually, the risk of Mediterranean fruit fly entering the United States is potentially very high. The risk of passengers bringing the pest into Florida or California from Mediterranean fruit fly-infested countries was determined with two novel models, one estimated seasonal variation in airline passenger number and the other defined the seasonal and spatial variability in Mediterranean fruit fly abundance. These models elucidated relationships among the risk factors for Mediterranean fruit fly introduction, such as amount of passenger traffic, routes traveled, season of travel, abundance of Mediterranean fruit fly in countries where flights departed, and risk of the pest arriving at destination airports. The risk of Mediterranean fruit fly being introduced into Florida was greatest from Colombia, Brazil, Panama, Venezuela, Argentina, and Ecuador during January–August, whereas primarily the risk to California was from Brazil, Panama, Colombia, and Italy in May–August. About three times more Mediterranean fruit flies were intercepted in passenger baggage at airports in Florida than California, although the data were compromised by a lack of systematic sampling and other limitations. Nevertheless, this study achieved the goal of analyzing available data on seasonal passenger flow and Mediterranean fruit fly population levels to determine when surveillance should be intensified at key airports in Florida and California.

1 March 2020 in Florida Entomologist
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Journal Article
Open access
AKArjun Khadka
Arjun Khadka
AHAmanda Hodges
Amanda Hodges
Norman Carey LepplaNorman Carey Leppla
Norman Carey Leppla
GTGlynn Tillman
Glynn Tillman
Eggs, nymphs, and adults of Halyomorpha halys were exposed to 15%, 35%, 55%, 75%, or 90% RH provided by glycerol-water solutions. Although egg hatch and nymphal survival occurred at all concentrations, they were highest at 55% to 90% RH. Nymphs exposed at the second instar reached the adult stage only at 55% to 90% RH. Females laid the greatest number of egg clutches at 55% RH. Therefore, we believe that H. halys could survive in Florida at 55% to 90% RH, but would be most prolific at 55%.

14 October 2020 in Environmental Entomology
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Journal Article
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Dakshina SealDakshina Seal
Dakshina Seal
ABAnil B Baniya
Anil B Baniya
RDRuhiyyih Dyrdahl-Young
Ruhiyyih Dyrdahl-Young
RHRobert C Hochmuth
Robert C Hochmuth
Norman Carey LepplaNorman Carey Leppla
Norman Carey Leppla
PDPeter DiGennaro
Peter DiGennaro
Wireworms are immature stages of click beetles (Coleoptera: Elateridae) and are considered a serious threat to sweet potato production in the southern United States. The major wireworm species collected in North Florida sweet potato fields in 2017 and 2018 were Conoderus scissus, C. rudis, C. amplicollis, and C. falli. These species vary in their behavior and biology. During a 2-yr study period, we conducted two insecticide field trials using eleven insecticides belonging to organophosphates, neonicotinoids, pyrethroids, and botanical classes, and three field trials using entomopathogenic nematode (EPN) species to control wireworms. In 2017, all insecticide treatments significantly reduced new feeding holes and total holes (old + new + other) as compared to the untreated control. In 2018, the result was similar with a few variations. In both years, all insecticides showed a percentage reduction in wireworm damage holes (2017: 34.88–96.19%; 2018: 12.38–97.02%) with the highest by Regent. In the EPN field study, one application of EPN near planting significantly reduced soil insects. In a laboratory study conducted at the Tropical Research and Education Center, UF-IFAS, chlorpyrifos caused higher percentage mortality of C. rudis (55.5%) than C. scissus (22.2%). At the present experiment rates, none of the insecticides caused the mortality of C. amplicollis. Heterorhabditids strain ‘FL-2122’ was more susceptible to chlorpyrifos than other strains of EPN.

1 March 2019 in Journal of Insect Science
Verified
Journal Article
Open access
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Norman Carey LepplaNorman Carey Leppla
Norman Carey Leppla
Patrick De ClercqPatrick De Clercq
Patrick De Clercq
The International Organization for Biological Control Global Working Group on Mass Rearing and Quality Assurance (MRQA) was established in 1980 as the Working Group on Quality Control (WGQC) to assure success of insect mass rearing for pest management that was being developed in the 1950s and 1960s. Due mostly to the efforts of WGQC, quality control became institutionalized in several insect mass rearing facilities during the 1980s. After addressing autocidal control programs, the WGQC concentrated on entomophagous insects, especially testing the quality of commercial biological control products. Universal Implementation of Quality Control for Mass-Reared Arthropods was finally achieved in the 1990s, having encompassed all aspects from insect production to field application and evaluation. This increased scope prompted a name change from WGQC to Arthropod Mass Rearing and Quality Control (AMRQC). Subsequently, the scope of the Working Group was expanded again and it was renamed MRQA to include a range of applications for mass-reared beneficial invertebrates. The geographic range of MRQA recently was extended beyond North and South America and Europe to include India. This expansion continued as insects for food and feed, networking and instruction, and legal and ethical issues were added to the most recent workshop held in Mexico. Thus, the MRQA continues to evolve as additional invertebrate organisms are mass produced for both established and novel applications.

1 March 2017 in Florida Entomologist
Verified
Journal Article
Open access
CPCory Penca
Cory Penca
AHAmanda Hodges
Amanda Hodges
LDLani Lei L. Davis
Lani Lei L. Davis
Norman Carey LepplaNorman Carey Leppla
Norman Carey Leppla
RHRobert Hochmuth
Robert Hochmuth
The occurrence of beneficial and pest arthropods collected from buckwheat companion plantings on a blueberry and a vegetable farm in north Florida was characterized. Similarity of arthropod diversity at the family level was intermediate (Sørensen index = 0.59). Significantly more pollinators and parasitoids but fewer pests were collected at the blueberry than the vegetable farm. The blueberry farm, therefore, achieved the goal of using companion plants to selectively enhance the impact of natural enemies. This goal was not accomplished at the vegetable farm because relatively large numbers of tarnished plant bugs and other pests attracted to the buckwheat were not controlled by the natural enemies. Se caracterizó la presencia de artrópodos benéficos y plaga recolectados de las plantaciones conjuntas de alforfón, arándanos y hortalizas en una granja de en el norte de la Florida. La similitud de la diversidad de artrópodos a nivel familiar fue intermedia (índice de Sørensen = 0,59). Significativamente se recolectaron más polinizadores y parasitoides, pero menos plagas en el arándano que en la granja de hortalizas. El huerto de arándanos, por lo tanto, logró el objetivo de utilizar plantas de compañía para aumentar selectivamente el impacto de los enemigos naturales. Esta meta no se logró en la granja de hortalizas debido a que un número relativamente grande del chinche Lygus lineolaris y otras plagas atraídas por el alforfón no fuerton controladas por los enemigos naturales.