René FH Sforza

United States Department of Agriculture | USDA · ARS-European Biological Control laboratory

Trophic relationships between plants and insects are not confined to biological interactions such as herbivory (i.e., direct consumption of one primary producer by a predator). In an ecological approach, many other interactions, trophic or even nontrophic, may influence plant herbivory by insects. These interactions are related to the complexity an...

A systematic review focused by plant on non-target impacts from agents deliberately introduced for the biological control of weeds found significant non-target impacts to be rare. The magnitude of direct impact of 43 biocontrol agents on 140 non-target plants was retrospectively categorized using a risk management framework for ecological impacts o...

Classical biological control remains the only tool available for permanent ecological and economic management of invasive alien species that flourish through absence of their co-evolved natural enemies. As such, this approach is recognized as a key tool for alien species management by the Convention on Biological Diversity (CBD), the European and M...

To better understand why medusahead (Taeniatherum caput-medusae) is invasive, we quantified soil N availability and characterized soil microbial communities between native and inva-sive populations. No consistent differences in soil N mineralization potentials were noted between native medusahead sites in Spain, Turkey, France, and Greece and two i...

Historical review of biological control, the main principles and major examples.

Tree of Heaven (ToH), Ailanthus altissima is a fast-growing tree native to China and Taiwan, but invasive in Europe and the U.S. where it disrupts urban and natural biocenoses. This invasive brings together successful strategies or traits including defense mechanisms and extrafloral nectaries. The Extra Floral Nectar (EFN) represents a significant...

The stink bug, Bagrada hilaris, is a pest of mainly Brassicaceae crops. It is native to Africa and Asia and was recently reported as invasive in the southwestern part of the USA and in South America. There are no mitigation programs in place that do not involve pesticides. Therefore, much attention has recently been paid to the study of this specie...

Invasive alien plant species (IAPs) are causing significant negative impacts on agricultural production, threatened native species and ecosystems, the services they provide and public health thereby affecting European biodiversity and its economy. IAPs invade all types of natural and managed habitat and their impacts, through increased numbers and...

The USA has been actively involved in classical biological control projects against invasive insect pests and weeds since 1888. Classical (importation) biological control relies upon natural enemies associated through coevolution with their target species at their geographic origin to also provide long-term, self-sustaining management where the pes...

The bagrada bug, Bagrada hilaris, is an invasive insect pest in the family Brassicaceae that causes economically important damage to crops. It was originally present in Asia, the Middle East, and Africa, and was reported as invasive in the southwestern part of the US, in Chile, and on a few islands in the Mediterranean Basin. In its native range, B...

This chapter focuses on the different stages of the process of classical biological control (CBC) through selected examples, including cottony cushion scale, oriental chestnut gall wasp, vine mealybug, fruit fly, bagrada stink bug and codling moth. The starting point of this long process is the search for natural enemies of species that are conside...

As of 2021, this chapter provides a brief overview of biological control agents selected worldwide against pests, that is, arthropods (insects and mites), weeds and plant diseases. Among predators, parasitoids, herbivores and pathogens, a minimum of 75 families are presented, distributed as follows: 52 families in eight insect orders, 19 families f...

The cold storage of host eggs has been utilized in the production of egg parasitoids used in biological control programs. However, similar stockpiling methods can lead to various responses depending on the parasitoid species considered. Hence, standardization of storage methods is difficult. The egg parasitoid Gryon gonikopalense Sharma, is current...

Host detection and parasitism by egg parasitoids involve host chemical recognition, spatial overlapping, and the ability to overcome physical barriers. Within the context of importation biological control, we examined the potential of Gryon gonikopalense (Hym.: Scelionidae), against the stinkbug pest, Bagrada hilaris (Hem.: Pentatomidae). Bagrada i...

French broom (Genista monspessulana) (Fabaceae) is a perennial species native to the Mediterranean basin. Introduced in the 19th century as an ornamental plant, it is currently invasive in California and Australia. The current research is focused on biocontrol with the use of the phytophagous weevil Lepidapion argentatum (Brentidae). Its capacity t...

Tree of heaven (Ailanthus altissima) is a fast-growing deciduous tree native to China, considered a serious invasive species worldwide, with several socio-economic and ecological impacts attributed to it. Chemical and mechanical methods have limited efficacy in its management, and biological controls may offer a suitable and sustainable option. Acu...

Plant invasions are rarely homogenous. Processes such as selection, drift, gene flow, and founding events can rapidly shape the genetic diversity and spatial population structure of an invasion. We investigated the diversity, origins and population structure of Verbascum thapsus (common mullein), an introduced plant in North America. Despite this s...

Molecular markers prove to be an invaluable tool in assessing the introduction dynamics, pattern of range expansion, and population genetics of an invasive species. Ventenata dubia (Leers) Coss. (Aveneae; ventenata) is a diploid, primarily self-pollinating, annual grass native to Eurasia and Northern Africa. The grass has a detailed herbarium colle...

Invasive stink bugs (Hemiptera: Pentatomidae) are responsible for high economic losses to agriculture on a global scale. The most important species, dating from recent to old invasions, include Bagrada hilaris (Burmeister), Halyomorpha halys (Stål), Piezodorus guildinii (Westwood), Nezara viridula (L.), and Murgantia histrionica (Hahn). Bagrada hil...

A biological control program is in development for two swallow-wort species (Vincetoxicum, Apocynaceae), European vines introduced into northeastern North America. One candidate agent is the defoliator Abrostola asclepiadis (Denis and Schiffermüller) (Lepidoptera: Noctuidae). The moth reportedly has up to two generations in parts of its native rang...

A popular review of biological approaches to control weeds in agricultural and environmental systems in Europe

The pentatomid bug Bagrada hilaris is a severe invasive alien pest of Brassicaceae crops, which first appeared in California in 2008 and is expanding to several southern U.S. states and South America. To answer the demand of growers for sustainable management methods, a biological control program started in 2015. The egg parasitoid Gryon gonikopale...

Lepidapion argentatum (Gerstaecker) (Brentidae) is a weevil from the Mediterranean region collected and recorded from French broom (Genista monspessulana) (L.) LAS Johnson (Fabaceae), a major invasive plant in the USA. We studied feeding and oviposition of L. argentatum under laboratory conditions. Overwintering adults can oviposit in either seed-p...

Lepidapion argentatum (Gerstaecker) (Brentidae) is a weevil from the Mediterranean region collected and recorded from French broom (Genista monspessulana) (L.) LAS Johnson (Fabaceae), a major invasive plant in the USA. We studied feeding and oviposition of L. argentatum under laboratory conditions. Overwintering adults can oviposit in either seed-p...

In weed biocontrol, there is a need for pre-release efficacy assessments for potential agents. Genista monspessulana ((L.) L. A. S. Johnson (Fabaceae), French broom) is an invasive perennial shrub in the western U.S. The galling weevil Lepidapion argentatum Gerstaecker is a potential biocontrol agent. The impact of increasing weevil density on gall...

Biological control of weeds is a globally-recognised approach to the management of some of the most troublesome invasive plants in the world. Accidental introductions of agents accounted for all weed biological control agent establishments in the European Union until 2010, but these examples include some current or emerging control successes both l...

Biological control of weeds is a globally recognised approach to the management of some of the most troublesome invasive plants in the world. Accidental introductions of agents accounted for all weed biological control agent establishments in the European Union until 2010, but these examples include some current or emerging control successes both l...

Determining the most likely source of an invasive pest species might help to improve their management by establishing efficient quarantine measures and heading the search of efficient biological control agents. Planococcus ficus is an invasive mealybug pest of vineyards in Argentina, California, Mexico, Peru and South Africa. This mealybug pest had...

Sample locations and information collected. Vine mealybug, Planococcus ficus (Hem.: Pseudococcidae) collection information showing country and locality (city or region), Global Position Satellite (GPS) coordinates when available, collector and date, whether samples were processed by CO1 or ITS1, if there is a museum deposited slide mount for the lo...

First reported in California in 2008, Bagrada hilaris (Hem.: Pentatomidae), a major pest of Brassicaceae, has now spread to several U.S. states and Mexico. We studied host phylogeography by sequencing CO1 from 20 bagrada populations and determined that Pakistan is the likely origin for invasive US populations. Sentinel host eggs were used to collec...

This proceedings contains papers dealing with issues affecting biological control, particularly pertaining to the use of parasitoids and predators as biological control agents. This includes all approaches to biological control: conservation, augmentation, and importation of natural enemy species for the control of arthropod targets, as well as oth...

Trophic relationships between plants and insects are not confined to biological interactions such as herbivory (i.e., direct consumption of one primary producer by a predator). In an ecological approach, many other interactions, trophic or even nontrophic, may influence plant herbivory by insects. These interactions are related to the complexity an...

A new morph of leafy spurge, Euphorbia esula L., was discovered in the floodplains of the Val de Saône (VDS), France. In this region, this emerging weed shows two different morph colours: the common “green” variant and a rarer “red” variant. We compared the sequence data for the plastid trnT–trnF region among individuals of both morphs from the VDS...

Investigating host specificity of Ustilago phrygica and impact for biological control of Taeniatherum caput-medusae (L.) Nevski

A systematic review focused by plant on non-target impacts from agents deliberately introduced for the biological control of weeds found significant non-target impacts to be rare. The magnitude of direct impact of 43 biocontrol agents on 140 non-target plants was retrospectively categorized using a risk management framework for ecological impacts o...

Since the 1990s, the negative ecological and economic impacts of the native plant leafy spurge Euphorbia esula L. (Euphorbiaceae), have increased in the floodplains of Val de Saône (France). Growing in dense patches, this latex-rich plant is toxic to cattle and when present in cut hay reduces the profitability of annually mowed grasslands. This eco...

Investigating the origins of invasive pop- ulations provides insight into the evolutionary and anthropogenic factors underlying invasions, and can inform management decisions. Invasive species intro- duced for horticultural purposes often have complex origins typified by multiple introductions of species, cultivars, and genotypes, and interspecific...

Bgpi : équipe 6 chapitre 34

The exotic invasive French broom, Genista monspessulana (Fabaceae), is a woody legume of major concern in the Western U.S. and other countries, including Australia, Chile, New Zealand, and South Africa. It displaces native flora and desirable forage species by forming dense monotypic stands, threatens arthropod diversity, is toxic to cattle, and in...

Aim Canada thistle (Cirsium arvense – Cardueae, Asteraceae) is one of the worst invasive plants world-wide. Native to Eurasia, its unintentional introduction into North America now threatens the native flora and is responsible for enormous agricultural losses. The goals of this study are to: (1) reconstruct the evolutionary history of C. arvense an...

Economic losses resulting from vineyard mealybug infestations have increased dra-matically during the past decade. In response, there has been a cosmopolitan effort to improve control strategies and better understand mealybug biology and ecology, as well as their role as vectors of plant pathogens. Mealybugs are named for the powdery secretions cov...

A simple molecular tool was developed and tested to identify seven mealybug species found in North American vineyards: Pseudococcus maritimus Ehrhorn, Pseudococcus viburni (Signoret), Pseudococcus longispinus (Targioni-Tozzeti), Pseudococcus calceolariae (Maskell), Planococcus ficus (Signoret), Planococcus citri (Risso), and Ferrisia gilli Gullan....

Background/Question/Methods The invasion of western North America by a number of Centaurea species has had enormous ecological and economic impacts there. Surprisingly, though it is found in 47 of the 50 states many aspects of the life histories of these species are not as well known as they should be. Comparative studies and experiments in contro...

The use of molecular techniques is rapidly growing as the tools have become more diverse and powerful, more widely available, and easier to implement. Molecular analyses are able to elucidate information about target weeds that is critical to improving control success, such as taxonomic clarification, evidence of hybridization and cryptic species,...

The alien invasive vines Vincetoxicum rossicum and Vincetoxicum nigrum (swallow-wort) are of major concern in eastern North America, where both species invade forested landscapes and threaten faunal and plant diversity. Among the few native natural enemies reported in Eurasia, the specialist chrysomelid, Chrysochus (Eumolpus) asclepiadeus (Coleopte...

Mealybugs (Hemiptera: Pseudococcidae) are major pests of a wide range of crops and ornamental plants worldwide. Their high degree of morphological similarity makes them difficult to identify and limits their study and management. We aimed to identify a set of markers for the genetic characterization and identification of complexes of taxa in the Ps...

Native to Eurasia, swallow-worts (" the ugly: " Vincetoxicum rossicum (Kleopov) Barbarich and V. nigrum L.-Apocynaceae) have invaded forested landscapes and prevented native plant regeneration in eastern North America. We first aimed to understand where the invasive populations of both species come from, and then evaluated the impact of potential b...

Invasive species' success may depend strongly on the genetic resources they maintain through the invasion process. We ask how many introductions have occurred in the North American weed Centaurea stoebe micranthos (Asteraceae), and explore whether genetic diversity and population structure have changed as a result of introduction. We surveyed indiv...

Biological invasions offer excellent systems to study the evolutionary processes involved in introductions of species to new ranges. Molecular markers can reveal invasion histories and the effects of introductions on amounts and structuring of genetic variation. We used five polymorphic microsatellite loci to elucidate genetic diversity and populat...

Surveys conducted SINCE 1998, showed that symptoms typical of Elm yellows (EY) were quite frequent in the elm conservatories of Nogent-sur-Vernisson and Guéméné-Penfao, France and on forest trees in several locations in western Europe. Phytoplasmas were detected in symptomatic trees and plants using Polymerase Chain Reaction amplification followed...

Crofton weed, Ageratina adenophora (Sprengel) R. King and H. Robinson, originally from Central America, was introduced into China in the 1940s. The weed spreads rapidly and is seriously damaging grasslands and hindering livestock production in southwestern China. To tackle the weed problem and allow the sustainable use of pastures, an integrated st...

Conférence internationale sur les ravageurs en agriculture, Montpellier 22 et 23 octobre 2008

The annual grass Taeniatherum caput-medusae (L.) Nevski (medusahead) is highly invasive on rangelands of the western United States. It originates from the Mediterranean basin and was introduced accidentally into North America in the late 1800s. To increase our knowledge of the soil factors that may contribute to its invasiveness, we conducted a rec...

The Agricultural Research Service of the United States Department of Agriculture has maintained a continuous European effort in classical biological control of exotic pests in the USA. The European Parasite Laboratory was established in France in 1919, while the European Weed Laboratory began operations in Rome in 1958. The two laboratories were me...

Unlike biocontrol of insect pests, biocontrol of invasive weeds is not largely studied in Eurasia, but remains an ecologically sound approach to invasive species management. The case study of silverleaf nightshade (Solanum elaeagnifolium) is a good example of a New World weed which has been introduced and is spreading over the Mediterranean Basin....

Knowing the origin of invasive taxa, whether multiple introductions have occurred, and levels of genetic variation relative to the native range, is vital to conducting rigorous tests of hypotheses to explain biological invasions. We explore phylogeographical relationships of two Eurasian knapweed taxa that are invasive in North America, Centaurea d...

Centaurea stoebe (subspecies C. s. stoebe and C. s. micranthos[S. G. Gmelin ex Gugler) Hayek] and Centaurea diffusa are Eurasian plant species that have invaded much of North America. We isolated seven microsatellite loci from C. stoebe and two loci from C. diffusa. All loci described here amplify in both species and have between six and 25 alleles...

Two closely related teasels (Dipsacales: Dipsacaceae, Dipsacus spp.) of European origin have become invasive weeds in the United States. Common teasel (Dipsacus fullonum L.) and cutleaf teasel (Dipsacus laciniatus L.) have likely been in North America for more than two centuries, having been introduced along with cultivated teasel [D. sativus (L.)...