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With more than 800 thousand tones sold abroad each year, Argentina is one of the leading exporters of peanuts in the world. However, the local production has been affected by smut, a disease caused by fungi Thecaphora frezii, which destroys the seeds of the fruits.

To provide a solution to this problem that leads to a loss of almost 40% of plantations, CONICET researchers participate in projects that aim to develop peanut resistant to smut. For this reason, they identified sources of resistance in wild species of Arachis as well as in old breeds and developed hybrids compatible with the varieties cultivated extensively for the industry.

The research work was jointly conducted with ‘El Carmen Hatchery’, the Universidad Nacional de Río Cuarto, the  Universidad Nacional de Córdoba, the Universidad Nacional del Nordeste and the National Peanut Research Laboratory (NPRL). The journals that published it were CropScience and PlosOne. Considering the development of these materials, the researchers estimate that in a few years there will be diverse commercial varieties of peanuts resistant to smut, what will recover the average performance of the peanut crop in Argentina.

“Smut is an endemic disease of Argentina that causes a loss of 40% in the production. For this reason, it is important to work on the solution to this problem. It is hard to find foreign researchers interested in this subject because they do not have it,” says one of the authors of the study, CONICET principal researcher at the  Instituto de Botánica del Nordeste (IBONE, CONICET – UNNE), Guillermo Seijo.

“Our contribution was to systematize the existing knowledge of the preliminary tests of peanut breed resistant to smut, which were obtained by the El Carmen through different improvement methodologies. Particularly, we used genetic tools to identify the sources of the resistance and the available resources in old breeds and in wild species to obtain it”, explains Francisco de Blas, Ph.D. fellow of CONICET at the Instituto Multidisciplinario de Biología Vegetal (IMBIV, CONICET – UNC).

One of the tasks was to obtain a ‘three-hybrid’ from the wild species Arachis correntina, Arachis cardenasii and Arachis batizocoi, whose chromosomes were duplicated to be compatible with the commercial variety Arachis hypogaea. In the second one, the resistance was transferred from old peanut breeds of South America. In both cases, scientists developed populations to study the genetic structure of the character and enable the development of genetic markers linked to resistance.

The study aims at expanding the existing variability in commercial varieties through the development of pre-improvement materials, which still present character of wild species or old breeds that have no value for the industry. These materials have already been incorporated into the breeding programs that seek to develop commercial varieties resistant to smut in the short term.

“We have managed to transfer the resistance of these materials, which behave as resistant, to segregating populations for generic and genomic studies of character,” de Blas says. Now, the researchers work to determine which portions of the genome are linked to resistance. For the researchers, in the near future, it will be possible to identify the genomic regions associated with resistance and develop DNA markers to accelerate the programs to obtain resistant commercial varieties.

Although the way to obtain commercial peanut resistant to smut is quite advanced, the main objective of CONICET scientists is to determine the genetic structure of resistance and have the tools to accelerate the process of generating new varieties with better characteristics. “To achieve this, the collaboration between scientific institutions and the productive sector is vital. In this project, our relationship with ‘El Carmen Hatchery’ was essential and we hope to continue obtaining good results from this interaction,” de Blas concludes.

References

de Blas, F. J., Bressanoc, M., Teichd I., Balzarinie, M., Ariasf, R.S., Manifestog, M.M., et al. (2019) Identification of Smut Resistance in Wild Arachis Species and its Introgression into Peanut Elite Lines. Crop Science Vol. 59 No. 4, p. 1657-1665. http://dx.doi.org/10.2135/cropsci2018.10.0656

Bressano, M., Massa, A.N., Arias, R.S., de Blas, F., Oddino, C., Faustinelli, P.C., et al. (2019) Introgression of peanut smut resistance from landraces to elite peanut cultivars (Arachis hypogaea L.). PLoS ONE 14(2): e0211920. https://doi.org/10.1371/journal.pone.0211920

This article was originally published in CONICET

A new study determined that river stingray populations in Argentina have decreased due to fishing.

In the mightiest rivers of South America there are fish little known for science: river stingrays. They are related to sharks and other marine ancestors. Their size can be up to one and a half meters and they can weigh more than 200 kilos.

One study conducted by researchers at the Instituto de Biología Subtropical (IBS, CONICET – UNaM) of the province of Misiones published today in Biological Conservation indicates that the stingrays populations of Paraná river have declined in the last 11 years. The study, based on surveys carried out by institutions that belong to the Ministerio de Agroindustrias de la Nación, proves that the decrease in the number of specimens is related to fishing.

The research covered the area from the cities of Resistencia and Corrientes up to the Paraná river delta –from the mouth to the Río de la Plata–, where six from the 32 fresh water species in the world. “Our work managed to test the stingray’s abundance trend and develop proposals to implement the measures to preserve it, considering that we are in a great diversity area”, Luis Lucifora, CONICET independent researcher at the IBS Puerto Iguazú node and first author of the publication.

The experts explain that the type of fishing that affect stingrays are various. From the city of Resistencia, in Chaco, up to Reconquista, in Santa Fe, sport fishing is the main practice. There are also fishermen that look for Pseudoplatystoma corruscans “surubí”, which is captured with a mesh, a large opening net, in the main bed of the river.

Despite the fact that stingrays are caught with this method, the amount is not as important as in the area that covers the center of Santa Fe until the Paraná delta, where the commercial fishing of Prochilodus lineatus “sábalo” takes place. Fishermen do it with smaller nets in a place known as floodplain, which are small lakes and rivers that appear when the river lowers and disappears or rises. “This is the most common habitat for the stingrays, so this the place where most specimens are obtained and where the decrease is most visible”, Lucifora describes.

Although in these cases the stingrays are not the last objective of fishing, the specimens are captured and many times mutilated. “When the fishermen find a stingray, the first thing they do it is to cut its tail because it has one sting to defend itself. As it is not what they were looking for, they give them back to the river to let them survive. In the surveys, we noticed that a great number of these species are in those conditions. This helped us to relate the abundance in different parts of the Paraná with the fishing pressure. The result was very clear: the areas that have a larger number of mutilated stingrays have a smaller amount of these fish”, the author of the study.

At the Iguazú IBS, Lucifora leads a group of researchers that took the studies on these animals to know their biology and provide more information for their conservation. “The last research on river stingrays conducted in Argentina was from the 70s. The project we are carrying out, in which different groups of scientists make contributions, aims at retaking the line of research that was abandoned 40 years ago”, the scientist describes.

“If nobody takes measures, the abundance of stingrays in Paraná –which is one of the rivers with the greatest diversity in the country–, is going to decrease. Firstly, it is very important to have all the middle part segment free from dams because one of the most sensitive species, the giant stingray (Potamotrygon Brachyura), is closely linked to running waters”, Lucifora concludes. Moreover, this shows the need to continue the advances on researches so as to know the reproductive biology of the stingrays to know how much can be exploited as their consumption has risen.

This piece was originally published on CONICET. It can be found in its entirety here

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Researchers propose new perspectives to study prehistoric mammals.

During the last 30 million years until their extinction 10 thousand years ago, glyptodonts were one of the great mammals that inhabited South America. With their body completely protected with a shell, these mammals were among the most impressive of the continental fauna and managed to migrate to Central and North America.

Despite the great number of fossil species of glyptodonts that exist in the entire American continent, the evolution of these great herbivorous mammals has some uncertainties. In order to know more about this process, Argentine and North American scientists plan new studies.

During a recent trip to the USA, researchers at the Centro de Ecología Aplicada del Litoral (CECOAL, CONICET– UNNE) in Corrientes began a joint study with scientists of the Museum of Northern Arizona. The research was about one preliminary analysis of the different collections that contains remains of glyptodonts. This first meeting allowed scientists to exchange ideas about the species from different parts of South and North America and to formulate new hypothesis about the diversity of these mammals. At the same time, those theories are going to be examined as part of a joint project with researchers at the Museo de La Plata and experts from other countries in the future.

“According to the remains recently found in Venezuela and Brasil, our studies have shown that North American glyptodonts entered South America at some moment of the Pleistocene, a fact that is possibly related to glaciation that transformed Central America into an enabling environment for migration. So this species had not only arrived in North America but also come back to South America some millions of years later with a different gender”, Alfredo Zurita, CONICET independent researcher at the CECOAL and main specialist in glyptodonts, explains.

Unlike other related mammals (such as sloths and armadillos), glyptodonts were not studied in depth despite having been so common in all America. The aim of Argentine and North American paleontologists is to carry out a detailed study comparing the diversity and evolution in South and North America of the glyptodonts, one particular subfamily within glyptodonts. With these results, scientists will be able to establish differences or similarities these mammals had in the various areas and get to know more about their evolution.

“We knew very little about glyptodonts except for the fact that within the remarkable diversity of the glyptodonts that inhabited South America, they were the only ones that arrived in North America with a very particular story. We estimate that its origin in the north of South America traces back to 12 millions of years ago and they reached the south of South America in 8 millions of years ago thanks to the fact that at that time there were great plains –what was later called the “Southern Plains Age” –, which will facilitate migration processes. However, glyptodonts seemed to have been rare in those latitudes during millions of years until about two millions years ago when they suddenly became one of the most common groups of glyptodonts”, Zurita describes.

With the North American team led by paleontologist David Gillette of the Museum of Northern Arizona, Argentine scientists visited different paleontological collections that have material on glyptodonts. “This meeting was essential for both research teams because it allowed us to compare ideas, interact and enlarge the prospect of the studies on glyptodonts and their migratory process carried out in the entire continent. Furthermore, it produced a new prospect so we have to begin to work on radically different concepts based on a very slow morphological evolution and on the fact that the diversity had always been greater in South America compared to Central and North America”, the researcher explains.

“It was thought that glyptodons had evolved quickly since they entered North America because they found a different ecosystem to get adapted to. However, what we observed now is that they were nearly no important morphological changes in almost 4 millions of years. In fact, it is possible that 4 million years old fossils and 30 million years olds correspond to the same species. Even its geographical distribution was fairly limited as no glyptodons reached 35 North latitude. The diversity of glyptondts in Central and North America seems to be surprisingly low compared to what we observe in South America”, Zurita states.

“This new prospect makes us reinterpret a lot of information we thought we knew about the evolution and diversity of glyptodonts in general, in South and North America. This is an interesting process, typical of science: sometimes one has an idea for decades but cannot affirm it because there is something missing. Both researchers at the USA and us had to face the same situation and this meeting allowed us to adopt new perspectives for all”, the paleontologist concludes.

This piece was originally published on
CONICET. It can be found in its entirety here

Wild stingless bees provide the inhabitants of Baritú in Salta with pollen, wax, and propolis. Researchers study the uses and characteristics of these products for their conservation and value.

Before the introduction of the “European bee” (Apis mellifera), different melipona species – a group of native stingless bees-, were the main suppliers of honey for the native inhabitants of the American continent. Some communities that live in the yungas of Salta, maintain the habit of collecting the hives of these native bees and use their honey, pollen, wax, and propolis for medicinal and food purposes.

Studies performed by CONICET researchers described picking methods and how the inhabitants of Baritú use local melipona bees. The scientists had also conducted a botanical characterization of the honey, which helped to find that the bees feed mainly on native species flowers, providing the products with unique characteristics.

“The studies revealed that mostly all inhabitants use the products of the same local meliponas’ hives in a similar way. The honey and the pollen are used as food and ingredients of beverages and medicinal preparations, the wax is used for the production of candles, and the propolis as fuel element in ritual contexts”, Norma Hilgert, CONICET independent researcher at the Instituto de Biología Subtropical of Misiones (IBS, CONICET–UNaM) [Subtropical Biology Institute of Misiones].

The objective of these scientific studies, which were jointly developed with the Centro de Investigaciones y Transferencias de Jujuy (CIT, CONICET-UNJU) [Research and Transference Centre of Jujuy] is to value and make good use of the potential these resources for the community. This is a new outlook that combines the approach of cognitive anthropology, which focuses on the interface between biology and anthropology, with palynology, a discipline that is part of botany and is devoted to the study of pollen.

The survey of the relationship between the melliferous insects and the inhabitants of Baritú in Salta began in 2011 and was developed by the team composed of Norma Hilgert, a researcher at the IBS of Puerto Iguazú; Liliana Concepción Lupo, associate researcher at the CIT Jujuy and Fabio Fernando Flores, doctoral fellow at the CIT Jujuy.

One of the studies was specifically oriented to the botanic and geographical characterization of the honey of “mansita” (Plebeia intermedia), one of the more most well known and locally valued melipona bee species. Qualitative tests revealed that this species uses mainly native trees as a food source. “This is a very significant factor because the product comes from native flora and bees, what generates unique honey with a more interesting potential at a commercial level”, Lupo comments.

The inhabitants of the yungas who participate in this study work in family agriculture and transhumance livestock. Their family economy is of subsistence farming and most of the products obtained from the melipona bees are used for consumption. Nevertheless, in some families, the honey is particularly important because they are used as one product for bartering with other communities.

Hilgert comments that there is a project at the Ministerio de Ambiente y Desarrollo Sustentable de la Nación [Ministry of Environment and Sustainable Development] in which there will be new incorporation in the Código Alimentario Nacional [National Food Code]. It is about the Tetragonisca fiebrigi (jatei), a new species of melipona present in the north of Argentina, what will provide the possibility of developing the commercialization of the product as a practically exclusive resource of these communities. “Our studies show that there are other lesser-known honeybees that are vital for some communities and have a great potential to be developed in the future”, the scientist states.

In order to turn the honey into a new source of income for the inhabitants, there have been other initiatives. “Together with a beekeeper producer from Santa Fe, we conducted a pilot in which we raised “mansita” bees with the help of two local families. We practiced the transfer from the hive in the tree to a breeding box and identified how to take after this species in particular”, Fabio Flores comments. “We plan to track the progress and health of the hives in each of the visits to Baritú”, he adds.

The studies performed by the team of scientists from Misiones and Jujuy provided, from an ethnobiological and palynological perspective, the first contributions regarding the wild honey of the Andean populations and the food sources selected by the melipona bees. Through the development of this theme, the researchers aim to create tools for the production of these resources, promoting not only the conservation of the natural environments of these insects but also the economy of their inhabitants.

Before the introduction of the “European bee” (Apis mellifera), different melipona species – a group of native stingless bees-, were the main suppliers of honey for the native inhabitants of the American continent. Some communities that live in the yungas of Salta, maintain the habit of collecting the hives of these native bees and use their honey, pollen, wax and propolis for medicinal and food purposes.

Studies performed by CONICET researchers described picking methods and how the inhabitants of Baritú use local melipona bees. The scientists had also conducted a botanical characterization of the honeys, what helped to find that the bees feed mainly on native species flowers, providing the products with unique characteristics.

“The studies revealed that mostly all inhabitants use the products of the same local meliponas’ hives in a similar way. The honey and the pollen are used as food and ingredients of beverages and medicinal preparations, the wax is used for the production of candles, and the propolis as fuel element in ritual contexts”, Norma Hilgert, CONICET independent researcher at the Instituto de Biología Subtropical of Misiones (IBS, CONICET–UNaM) [Subtropical Biology Institute of Misiones].

The goal of these scientific studies, which were jointly developed with the Centro de Investigaciones y Transferencias de Jujuy (CIT, CONICET-UNJU) [Research and Transference Centre of Jujuy] is to value and make good use of the potential these resources for the community. This is a new outlook that combines the approach of cognitive anthropology, which focuses on the interface between biology and anthropology, with palynology, a discipline that is part of botany and is devoted to the study of pollen.

The survey of the relationship between the melliferous insects and the inhabitants of Baritú in Salta began in 2011 and was developed by the team composed of Norma Hilgert, researcher at the IBS of Puerto Iguazú; Liliana Concepción Lupo, associate researcher at the CIT Jujuy and Fabio Fernando Flores, doctoral fellow at the CIT Jujuy.

One of the studies was specifically oriented to the botanic and geographical characterization of the honeys of “mansita” (Plebeia intermedia), one of the more most well known and locally valued melipona bee species. Qualitative tests revealed that this species uses mainly native trees as food source. “This is a very significant factor because the product comes from native flora and bees, what generates a unique honey with a more interesting potential at a commercial level”, Lupo comments.

The inhabitans of the yungas who participate in this study work in family agriculture and transhumance livestock. Their family economy is of subsistence farming and most of the products obtained from the melipona bees are used for consumption. Nevertheless, in some families, the honeys are particularly important because they are used as one product for bartering with other communities.

Hilgert comments that there is a project at the Ministerio de Ambiente y Desarrollo Sustentable de la Nación [Ministry of Environment and Sustainable Development] in which there will be a new incorporation in the Código Alimentario Nacional [National Food Code]. It is about the Tetragonisca fiebrigi (jatei), a new species of melipona present in the north of Argentina, what will provide the possibility of developing the commercialization of the product as a practically exclusive resource of these communities. “Our studies show that there are other lesser-known honeybees that are vital for some communities and have a great potential to be developed in the future”, the scientist states.

In order to turn the honeys into a new source of income for the inhabitants, there have been other initiatives. “Together with a beekeeper producer from Santa Fe, we conducted a pilot in which we raised “mansita” bees with the help of two local families. We practised the transfer from the hive in the tree to a breeding box and indentified how to take after this species in particular”, Fabio Flores comments. “We plan to track the progress and health of the hives in each of the visits to Baritú”, he adds.

The studies performed by the team composed of scientists from Misiones and Jujuy provided, from an ethnobiological and palynological perpective, the first contributions regarding the wild honeys of the Andean populations and the food sources selected by the melipona bees. Through the development of this theme, the researchers aim to create tools for the production of these resources, promoting not only the conservation of the natural environments of these insects, but also the economy of their inhabitants.

*This piece was originally published on CONICET. It can be found in its entirety here