Alejandro Sosa

Fundación Para El Estudio De Especies Invasivas

Entomopathogenic fungi (EF) are important biocontrol agents due to their wide host range, easy application, and compatibility with phytosanitary products. Stink bugs (Hemiptera: Pentatomidae) are the most important rice pests in Argentina. Although there is information on the pathogenicity of EF against stink bug pests in rice fields, the natural i...

Parkinsonia aculeata L. (Fabaceae: Caesalpinioideae), native to the Americas, is a designated Weed of National Significance in Australia. The leaf‐feeding geometrid moth species, Eueupithecia cisplatensis Prout (Lepidoptera: Geometridae), was identified as a potential biological control agent of P. aculeata following native range surveys in Argenti...

Resumen La Ley de Educación Ambiental, recientemente promulgada, tiene como objetivo principal promover la educación ambiental e incorporar los nuevos paradigmas de la sostenibilidad a los ámbitos de la educación formal y no formal. Las especies invasoras causan daño en ambientes naturales, agrícolas y urbanos. Es tarea de la comunidad docente apoy...

Environmental education seeks to foster an appreciation for nature and the impact of humans on it while introducing citizens to scientific thinking. Biological invasions affect different aspects of life on earth and mandate urgent management actions. Education and public awareness are strongly recommended for successful prevention and management of...

The relationship between herbivory and latitude may differ between native and introduced populations of invasive plants, which can generate latitudinal heterogeneity in the strength of enemy release. However, still little is known about how latitudinal heterogeneity in herbivore pressure influences latitudinal variation in defense phenotypes of inv...

Las moscas son insectos cosmopolitas pertenecientes al orden Diptera y se encuentran dentro del suborden Brachycera que contiene alrededor de 120 familias. Este grupo, congrega géneros de gran importancia agronómica y ecológica, por contener especies biocontroladoras, polinizadoras, descomponedoras y saprófitas. Pese a su gran relevancia ecológica,...

Iris pseudacorus L. (Iridaceae) (Lirio amarillo) es una Especie Exótica Invasora (EEI) que causa grandes perjuicios ambientales y económicos en humedales de numerosos países del mundo. Desde su detección en Argentina en 1931, su rango de distribución ha ido en aumento, y actualmente la invasión afecta los humedales de al menos ocho provincias. En e...

Currently, the importance of the social dimension within the problem of Invasive Alien Species (IAS) is increasingly recognized, and the inclusion of public opinion and participation is crucial for the success of biocontrol programs. In this study, the social perception of IAS and Biological Control (BC) was comparatively evaluated in two countries...

En la actual crisis de biodiversidad, las Especies Exóticas Invasoras (EEI) son importantes por ser una de las principales causas de desequilibrios ecosistémicos. En este contexto, los estudios que apuntan a la detección temprana, distribución y la generación de mapas de invasiones, resultan fundamentales para los programas de prevención y manejo i...

The study of factors related to landscape in rice pest studies is important to visualize ecological patterns of these species within the wetland agroecosystem, and help to improve understandings about these patterns. Through several studies that have been conducted in Argentina, we detected the influence of a few local scale factors that would expl...

Hedychium coronarium (Zingiberales: Zingiberaceae), native to the Himalayas and southern China, has become an environmental weed in many countries around the world. Reported in several provinces of Argentina, H. coronarium constitutes a serious environmental problem especially in the wetlands of natural areas of Misiones Province, such as the Iguaz...

Re‐establishment of heritable latitudinal clines in growth‐related traits has been recognized as evidence for adaptive evolution in invasive plants. However, less is known about latitudinal clines in defense and joint clinal evolution of growth and defense in invasive plants. We planted 14 native Argentinean populations and 14 introduced Chinese po...

The yellow flag, Iris pseudacorus L. (Iridaceae) is an emergent perennial wetland plant native to the Palearctic region and has been dispersed worldwide as an ornamental plant. In the introduced range, it is highly invasive in natural and artificial waterbodies. Currently, this species is difficult to manage and continues to spread, causing signifi...

The aim of this paper is to shed light on the boundaries of two sympatric species of Cuernavaca, C. inexacta and C. longula, to enable further ecological studies. Species in this genus are associated with water hyacinths in wetlands of Northeastern Argentina (Paraná-Paraguay waterway system) and the Peruvian Amazon. This work lists new host records...

The Convention on Biological Diversity and the Nagoya Protocol establish that genetic resources shall be accessed only upon the existence of prior informed consent of the country that provides those resources and that benefits arising from their utilization shall be shared. Pursuant to both agreements several countries have adopted regulations on a...

Tibraca limbativentris (Hemiptera: Pentatomidae) is a major pest in neotropical rice agroecosystems. In autumn-winter, this pest takes refuge in rice stubble and in native vegetation, which allows it to re-colonize the crop during the rice growing season. However, it's still unknown whether this vegetation is a pest sink or is actually a natural tr...

Debido al amplio espectro de hospedadores, fácil producción, aplicación y compatibilidad con ciertos fungicidas y fitosanitarios, los hongos entomopatógenos son utilizados alrededor del mundo como micoinsecticidas en diversos cultivos. En la Argentina, estudios previos realizados en arroceras han reportado la patogenicidad de cepas fúngicas nativas...

The yellow flag (Iris pseudacorus L.) is an invasive exotic macrophyte that due to its ornamental value has been dispersed from the Palearctic to many countries of the world. In Argentina, it is found in natural, rural, urban and protected areas of different regions with a highly invasive behavior and causing serious damage, by altering the native...

Due to the broad spectrum of hosts, easy production, application and compatibility with certain fungicides and phytosanitary products, entomopathogenic fungi are used around the world as mycoinsecticides in various crops. In Argentina, previous studies in rice fields have reported the pathogenicity of native fungal strains on hemipteran pests. Howe...

Alligator weed (Alternanthera philoxe-roides (Martius) Grisebach) is an amphibious invasive plant native to South America. It is an allopolyploid that, in Argentina, possess two cytotypes, tetraploids and hexaploids. In the exotic range, the plant is biologically controlled with flea beetle Agasicles hygrophila Selman and Vogt but with different le...

Although Argentina treasures a vast area covered by wetlands, many of them are negatively impacted by the presence of Alien Invasive Plants. Iris pseudacorus L. (Iridaceae) (Yellow Flag) is an alien invasive weed that is native to Europe, northern Africa and western Asia, and introduced around the world mainly for its ornamental value. In the intro...

Book chapter in "Malezas e Invasoras de la Argentina" , Editores: Osvaldo Fernandez, Eduardo Leguizamón, Horacio Acciaresi

During the last hundred years, plants from Argentina (e.g. water hyacinth and alligator weed) have been accidentally or deliberately transported to other countries where they became invasive weeds. In 1962, the Agriculture Research Service (ARS) of the United States Department of Agriculture established the South American Biological Control Laborat...

Cuernavaca longula is a phloem‐feeding insect associated with the aquatic invasive weed Eichhornia crassipes, and is distributed in South America from Peru to Northern Argentina. It was studied and proposed as a potential biocontrol agent demonstrating its host affinity to water hyacinth through host specificity and damage studies. However, the com...

El “Lirio amarillo”, Iris pseudacorus (Iridadeae) es una planta palustre nativa de Europa, norte de África y oeste de Asia que ha sido dispersada e introducida en diferentes partes del mundo, incluyendo Canadá, Estados Unidos, Argentina, Chile, Uruguay, Australia, Nueva Zelanda y Sudáfrica. En muchas áreas naturales dentro del rango introducido, es...

Rice cultivation emerged in China more than 8000 years ago and is currently one of the crops with the greatest dispersion worldwide. Upon arriving in Argentina, it was initially established in the Province of Misiones around the 17th century. At that time, several herbivorous insects native to the region adapted well to the new resources offered by...

In Argentina, 45.19% of rice production is concentrated in the province of Corrientes. However, studies of pests and their natural enemies in these rice fields are scarce, which makes difficult the use of sustainable management options. We studied the hibernating population of the rice stem stink bug Tibraca limbativentris Stål (Hemiptera: Pentatom...

The rice stem bug, Tibraca limbativentris is one of the most important pests of economic importance in Latin America and the most difficult to manage in rice fields of the Northeast of Argentina (NEA). This pest produces annual economic losses, that can reach 65.2 kg/ha in Irrigated rice crops. When rice is absent, this bug takes refuge in native v...

La tucura Cornops aquaticum habita en humedales del Neotrópico desde el sur de México hasta el centro de Argentina y Uruguay, y se asocia frecuentemente con plantas de la familia Pontederiaceae, principalmente el camalote Eichhornia crassipes. Esta planta acuática se ha convertido en la especie plaga más importante de cuerpos de agua naturales y ar...

Classical biological control –or biocontrol- is a form of pest management comprising the release of specialized natural enemies (biocontrol agents) of an exotic pest. Classical biocontrol agents are scientifically selected from among the natural enemies the pest has in its native region. However biological control is firmly resisted in many countri...

Saltcedars are woody plants in the genus Tamarix L. (Caryophyllales: Tamaricaceae) and are native to Eurasia and Africa. Several species have become invasive in the Americas, Australia and South Africa. In Argentina there are four species of Tamarix distributed in arid, semi-arid and coastal areas of most provinces. The taxonomic isolation of Tamar...

Eichhornia crassipes and Eichhornia azurea are common invasive aquatic plants in Neotropical wetlands. These plants share species for their biological control, such as curculionoids of the genus Neochetina and the acridium Cornops aquaticum. In this study the herbivory of these specific insects was analyzed in leaves of E. azurea and E. crassipes,...

Alien plants produce severe environmental and economic losses in the territories they invade. Modelling the spatial distribution of alien species as a function of the environment in the native range has therefore become an essential first step in the struggle against invasions. Phyla nodiflora var. minor is a fast-growing perennial herb native to S...

Phenotypic plasticity has been proposed as an important adaptive strategy for clonal plants in heterogeneous habitats. Increased phenotypic plasticity can be especially beneficial for invasive clonal plants, allowing them to colonize new environments even when genetic diversity is low. However, the relative importance of genetic diversity and pheno...

Kuschelina bergi (Harold, 1881) is being studied to be evaluated as a natural enemy of Phyla nodiflora var. minor (Hook.) N. O'Leary & Mulgura (Verbenaceae), an invasive weed in Australia. Eggs, and 1st and 3rd instar larvae are described and illustrated for the first time. The following characters distinguish Kuschelina bergi: presence of two medi...

Flea beetles of alligator weed, Alternanthera philoxeroides (Martius) Grisebach (Amaranthaceae), were collected in Argentina, Uruguay, Paraguay, and Brazil. Species in the genera Disonycha Chevrolat, Agasicles Jacoby, Systena Chevrolat and Phenrica Bechyné were frequently found on this weed. Phenrica littoralis (Bechyn6) was the most abundant withi...

More than 73,000 Megamelus scutellaris (Hemiptera: Delphacidae) were released in Florida over a 2 to 3 yr period at 10 sites in an attempt to establish sustainable populations on waterhyacinth, Eichhornia crassipes Mart. Solms (Commelinales: Pontederiaceae). Insect populations persisted at most sites including those furthest north and consecutive o...

The delphacid Lepidelphax pistiae was found on water lettuce in Argentina. Nymphs and adults did not survive past seven days on 29 species of test plants, and no progeny were produced. In contrast, survival and reproduction were high on water lettuce. Results suggest that L. pistiae is monospecific to water lettuce.

Taosa longula Remes Lenicov (Hemiptera: Dictyopharidae), a planthopper native to South America, is a candidate for the biological control of water hyacinth, Eichhornia crassipes (Mart.) Solms-Laubach (Pontederiaceae), a serious weed worldwide. Biological control requires agents that are not only specific but also effective. Damage caused by sap-suc...

To investigate how stem anatomical structure is linked to growth and resistance to stem-boring insects in a herbaceous species, six populations of alligatorweed (Alternanthera philoxeroides) were grown in a common garden. Stem growth rate (GR) of A. philoxeroides and pupation rate as an estimate of resistance to a stem-boring insect (Agasicles hygr...

Megamelus scutellaris Berg (Delphacidae) and Taosa (Cuernavaca) longula Remes Lenicov (Dictyopharidae) are specialist planthoppers that feed and reproduce on the invasive aquatic weed, Eichhornia crassipes (Martius) Solms-Laubach (Pontederiaceae). They overlap geographically in several regions of South America and may, therefore, interact and compe...

Plant genotypic effects can alter insects’ ability of utilizing their host plant. Alligator weed, Alternanthera philoxeroides, is a South American amphibious Amaranthaceae, which invades aquatic and terrestrial habitats. Populations with varying morphotypes and cytotypes were identified and further associated with a polyploid hybrids complex in Arg...

The delphacid Megamelus scutellaris Berg was evaluated for host specificity and potential impact as part of a biological control program targeting Eichhornia. crassipes. Survival and development of adults and nymphs were used as metrics with no-choice, two-choice, nymph transfer, and sustainability tests conducted under quarantine conditions. A tot...

Egg parasitoids (Hymenoptera: Eulophidae, Mymaridae, and Platygastridae) of Megamelus spp. (Hemiptera: Delphacidae) in Argentina are reviewed and keyed. Four new species are described: Anagrus (Anagrus) empanadus Triapitsyn, sp. nov. (Mymaridae, parasitoid of M. scutellaris Berg feeding on water hyacinth, Eichhornia crassipes (Martius) Solms-Laubac...

Knowledge about the life-history traits of native conspecifics of exotic invasive plants can be of fundamental importance in exploring their origin of invasiveness and disentangling distinct invasion mechanisms. We conducted a common garden experiment to examine genetically based differentiation in growth and biomass allocation among three native A...

ABSTRACT. Egg parasitoids (Hymenoptera: Eulophidae, Mymaridae, and Platygastridae) of Megamelus spp. (Hemiptera: Delphacidae) in Argentina are reviewed and keyed. Four new species are described: Anagrus (Anagrus) empanadus Triapitsyn, sp. nov. (Mymaridae, parasitoid of M. scutellaris Berg feeding on water hyacinth, Eichhornia crassipes (Martius) So...

The flea beetle Systena silvestrii Bechyné 1957 was studied in context with the evaluation of natural enemies of the alligator weed, Alternanthera philoxeroides (Martius) Grisebach (Amaranthaceae). The female is described and the holotype male is redescribed adding new diagnostic characters: mouthparts, hind wings, metendosternite, male and female...

To detect biocontrol agents of the invasive aquatic weed Eichhornia crassipes (Martius) Solms-Laubach (Pontederiaceae), surveys were conducted in the basins of the Paraná and Uruguay rivers in Argentina and the basin of the Amazon river in Peru and Brazil. Among the captured delphacids, Megamelus scutellaris Berg was the most abundant. Berg origina...

The five immature stages of Megamelus scutellaris Berg (Hemiptera: Delphacidae) are described and illustrated. The main characters that distinguish the various stages are body size, number of tarsomeres and tibial spines, color, and number of teeth on the metatibial spur. New biological data based on laboratory rearing and field observations show t...

These proceedings contain the full-length papers and abstracts of papers presented at the symposium. Subjects covered include: ecology and modelling in biological control of weeds; benefits, risks and cost analysis of biological weed control; target and biological control agent selection; pre-release specificity and efficacy testing; regulations an...

The genus Megamelus Fieber (Hemiptera: Delphacidae), frequently associated with aquatic plants, includes four species in South America. One of these species, Megamelus scutellaris Berg, was the only species previously recorded in Argentina. In recent explorations in wetlands of South America (northeastern Argentina, eastern Peru, and southeastern B...

The planthopper Megamelus scutellaris (Hemiptera: Delphacidae) is a potentially valuable insect for biological control of waterhyacinth (Eichhornia crassipes (Mart.) Solms.: Pontederiaceae), a serious aquatic weed in many tropical and subtropical countries. Field surveys done in South America revealed that this insect is sympatric with waterhyacint...