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Balancing birds and biofuels: Grasslands support more species than cornfields

In Wisconsin, bioenergy is for the birds. Really.

In a study published today in the journal PLOS ONE, University of Wisconsin-Madison and Wisconsin Department of Natural Resources (DNR) scientists examined whether corn and perennial grassland fields in southern Wisconsin could provide both biomass for bioenergy production and bountiful bird habitat.

The research team found that where there are grasslands, there are birds. Grass-and-wildflower-dominated fields supported more than three times as many bird species as cornfields, including 10 imperiled species found only in the grasslands. These grassland fields can also produce ample biomass for renewable fuels.

Monica Turner, UW-Madison professor of zoology, and study lead author Peter Blank, a postdoctoral researcher in her lab, hope the findings help drive decisions that benefit both birds and biofuels, too, by providing information for land managers, farmers, conservationists and policy makers as the bioenergy industry ramps up, particularly in Wisconsin and the central U.S.

“As bioenergy production demand increases, we should pay attention to the ecological consequences,” says Turner.

This is especially true for grassland birds, as populations of species like the eastern meadowlark, dickcissel and the bobolink have declined in recent decades.

The study began when UW-Madison’s Carol Williams, coordinator of the Wisconsin Grasslands Bioenergy Network, and the DNR’s David Sample approached Turner and asked for her help. They wanted to know: “What are the implications of the decisions we make about how we use our lands?” says Turner.

The research team carefully selected 30 different grassland sites — three of which are already used for small-scale bioenergy production — and 11 cornfields in southern Wisconsin. Over the course of two years, the researchers characterized the vegetation growing in each field, calculated and estimated the biomass yields possible, and counted the total numbers of birds and bird species observed in them.

According to Blank and Turner, the study is one of the first to examine grassland fields already producing biomass for biofuels and is one of only a few analyses to examine the impact of bioenergy production on birds.

While previous studies suggest corn is a more profitable biofuel crop than grasses and other types of vegetation, the new findings indicate grassland fields may represent an acceptable tradeoff between creating biomass for bioenergy and providing habitat for grassland birds. The landscape could benefit other species, too.

Because they are perennial, the grassland fields can also be used year after year, following best management practices that preserve the health of the soil and provide reliable habitat for migratory birds.

“Plant diversity is good for wildlife diversity,” says Blank. “Our study suggests diverse bioenergy crop fields could benefit birds more so than less diverse fields.”

Among the grasslands studied, the team found monoculture grasses supported fewer birds and fewer bird species than grasslands with a mix of grass types and other kinds of vegetation, like wildflowers.

… new findings indicate grassland fields may represent an acceptable tradeoff between creating biomass for bioenergy and providing habitat for grassland birds.

The team found that the presence of grasslands within one kilometer of the study sites also helped boost bird species diversity and bird density in the area.

This is an opportunity, Turner says, to inform large-scale land use planning. By locating biomass-producing fields near existing grasslands, both birds and the biofuels industry can win.

Incentives for a conservation-minded approach could be used to help offset potential differences in profit, the researchers suggest. They also add that the biomass yields calculated in the study may represent the low end of what is possible, given that one of the two study years, 2012, occurred during a significant drought period in the state.

“The study shows species generally really benefit from the practice,” says Blank. “We really can produce bioenergy and provide habitat for rare birds in the state.”

Agriculture and Food News — ScienceDaily

Unusual host preference of a moth species could be useful for biological control

A team of Iranian researchers from the Rice Research Institute of Iran have discovered that Gynnodomorpha permixtana, a well-known moth species from Europe and Asia, has changed its host preferences in order to adjust to Iran’s northern region environmental conditions. The importance of this adaptation for biological control of problematic weeds in rice fields and the biology of the moth on new host plant have been described in the open access journal Nota Lepidopterologica.

The larvae of G. permixtana have been so far reported to feed on the seeds and flowers of plant species such as water-plantain, eyebright, lousewort, bitter root and European yellow-rattle, which are weeds commonly present across Europe and Asia. A new study of the populations in northern Iran, however has revealed a new host — Sagittaria trifolia, commonly known as arrowhead.

This new discovery suggests that climatic and environmental conditions in northern regions of Iran resulted in the choice of a new new host plant, and provides an exciting insight into how adaptation mechanisms work.

Arrowheads are groups of problematic perennial broadleaf weeds that thrive in rice fields and waterways. Favorable climatic condition after rice harvesting results in continued activity and thriving populations throughout the year.

The economic importance of this weed has prompted researchers from the Rice Research Institute of Iran to seek for possible solutions for the management of arrowhead. Their studies have revealed that the larvae of a certain moth species feeding on the fruits and seeds of the problematic weed, can lead to a dramatic decrease of its germination potential.

After this discovery the moth was sent for identification to Dr Leif Aarvik from the Natural History Museum, University of Oslo, who have diagnosed the species as the commonly known G. permixtana, which was in this case demonstrating a very uncommon host preference.

‘To our surprise, it looks like this moth chose new host plant in Iran. This moth was reported in 2009 from the northern regions of the country, but its host plant was unknown. Its usual host plants, such as water-plantain, also grow in Iran but peculiarly we couldn’t find its damage symptoms on them. That made this moth host range and biology in Iran rather mysterious at that point, and the recent discovery of arrowheads as its preferred host in the region brings even more peculiarity in the story.’ commented the lead author of the study Atousa Farahpour Haghani a Phd student from, Rice Research Institute of Iran.

‘Many factors can possibly influence host plant choice including food quality and quantity, climatic conditions, synchronization, physiological conditions in both insect and food plant, genetic modifications etc. Some of these factors are not stable and change in different environmental conditions, so an insect can change its choice of food plant on the basis of seeking the most beneficial complex of factors. It seems that in the northern regions of Iran, and luckily for rice crops, the problematic arrowheads present the best choice for G. permixtana.’ added Haghani.

Story Source:

The above story is based on materials provided by Pensoft Publishers. The original story is licensed under a Creative Commons License. Note: Materials may be edited for content and length.

Agriculture and Food News — ScienceDaily

Unusual host preference of a moth species could be useful for biological control

A team of Iranian researchers from the Rice Research Institute of Iran have discovered that Gynnodomorpha permixtana, a well-known moth species from Europe and Asia, has changed its host preferences in order to adjust to Iran’s northern region environmental conditions. The importance of this adaptation for biological control of problematic weeds in rice fields and the biology of the moth on new host plant have been described in the open access journal Nota Lepidopterologica.

The larvae of G. permixtana have been so far reported to feed on the seeds and flowers of plant species such as water-plantain, eyebright, lousewort, bitter root and European yellow-rattle, which are weeds commonly present across Europe and Asia. A new study of the populations in northern Iran, however has revealed a new host — Sagittaria trifolia, commonly known as arrowhead.

This new discovery suggests that climatic and environmental conditions in northern regions of Iran resulted in the choice of a new new host plant, and provides an exciting insight into how adaptation mechanisms work.

Arrowheads are groups of problematic perennial broadleaf weeds that thrive in rice fields and waterways. Favorable climatic condition after rice harvesting results in continued activity and thriving populations throughout the year.

The economic importance of this weed has prompted researchers from the Rice Research Institute of Iran to seek for possible solutions for the management of arrowhead. Their studies have revealed that the larvae of a certain moth species feeding on the fruits and seeds of the problematic weed, can lead to a dramatic decrease of its germination potential.

After this discovery the moth was sent for identification to Dr Leif Aarvik from the Natural History Museum, University of Oslo, who have diagnosed the species as the commonly known G. permixtana, which was in this case demonstrating a very uncommon host preference.

‘To our surprise, it looks like this moth chose new host plant in Iran. This moth was reported in 2009 from the northern regions of the country, but its host plant was unknown. Its usual host plants, such as water-plantain, also grow in Iran but peculiarly we couldn’t find its damage symptoms on them. That made this moth host range and biology in Iran rather mysterious at that point, and the recent discovery of arrowheads as its preferred host in the region brings even more peculiarity in the story.’ commented the lead author of the study Atousa Farahpour Haghani a Phd student from, Rice Research Institute of Iran.

‘Many factors can possibly influence host plant choice including food quality and quantity, climatic conditions, synchronization, physiological conditions in both insect and food plant, genetic modifications etc. Some of these factors are not stable and change in different environmental conditions, so an insect can change its choice of food plant on the basis of seeking the most beneficial complex of factors. It seems that in the northern regions of Iran, and luckily for rice crops, the problematic arrowheads present the best choice for G. permixtana.’ added Haghani.

Story Source:

The above story is based on materials provided by Pensoft Publishers. The original story is licensed under a Creative Commons License. Note: Materials may be edited for content and length.

Agriculture and Food News — ScienceDaily

Unusual host preference of a moth species could be useful for biological control

A team of Iranian researchers from the Rice Research Institute of Iran have discovered that Gynnodomorpha permixtana, a well-known moth species from Europe and Asia, has changed its host preferences in order to adjust to Iran’s northern region environmental conditions. The importance of this adaptation for biological control of problematic weeds in rice fields and the biology of the moth on new host plant have been described in the open access journal Nota Lepidopterologica.

The larvae of G. permixtana have been so far reported to feed on the seeds and flowers of plant species such as water-plantain, eyebright, lousewort, bitter root and European yellow-rattle, which are weeds commonly present across Europe and Asia. A new study of the populations in northern Iran, however has revealed a new host — Sagittaria trifolia, commonly known as arrowhead.

This new discovery suggests that climatic and environmental conditions in northern regions of Iran resulted in the choice of a new new host plant, and provides an exciting insight into how adaptation mechanisms work.

Arrowheads are groups of problematic perennial broadleaf weeds that thrive in rice fields and waterways. Favorable climatic condition after rice harvesting results in continued activity and thriving populations throughout the year.

The economic importance of this weed has prompted researchers from the Rice Research Institute of Iran to seek for possible solutions for the management of arrowhead. Their studies have revealed that the larvae of a certain moth species feeding on the fruits and seeds of the problematic weed, can lead to a dramatic decrease of its germination potential.

After this discovery the moth was sent for identification to Dr Leif Aarvik from the Natural History Museum, University of Oslo, who have diagnosed the species as the commonly known G. permixtana, which was in this case demonstrating a very uncommon host preference.

‘To our surprise, it looks like this moth chose new host plant in Iran. This moth was reported in 2009 from the northern regions of the country, but its host plant was unknown. Its usual host plants, such as water-plantain, also grow in Iran but peculiarly we couldn’t find its damage symptoms on them. That made this moth host range and biology in Iran rather mysterious at that point, and the recent discovery of arrowheads as its preferred host in the region brings even more peculiarity in the story.’ commented the lead author of the study Atousa Farahpour Haghani a Phd student from, Rice Research Institute of Iran.

‘Many factors can possibly influence host plant choice including food quality and quantity, climatic conditions, synchronization, physiological conditions in both insect and food plant, genetic modifications etc. Some of these factors are not stable and change in different environmental conditions, so an insect can change its choice of food plant on the basis of seeking the most beneficial complex of factors. It seems that in the northern regions of Iran, and luckily for rice crops, the problematic arrowheads present the best choice for G. permixtana.’ added Haghani.

Story Source:

The above story is based on materials provided by Pensoft Publishers. The original story is licensed under a Creative Commons License. Note: Materials may be edited for content and length.

Agriculture and Food News — ScienceDaily

New species of spider wasp may use chemical signals from dead ants to protect nest

A new species of spider wasp, the ‘Bone-house Wasp,’ may use chemical cues from dead ants as a nest protection strategy, according to a recent study published July 2, 2014 in the open-access journal PLOS ONE by Michael Staab from University of Freiburg, Germany, and his colleagues from China and Germany.

Wasps use a wide variety of nest protection strategies, including digging holes or occupying pre-existing cavities such as in wood. Previous studies showed that the nests of cavity-nesting wasps contain several brood cells separated by thin walls of plant debris, resin, or soil. Once the females have finished constructing the nest, laying eggs, and providing food, they construct an outermost vestibular cell to close the nest. After construction, female wasps abandon the brood and do not care for their offspring anymore. Nest protection strategies play a central role in brood survival, and in this study, scientists interested in better understanding these strategies collected ~800 nests of cavity-nesting wasps with ~1900 brood cells belonging to 18 species in South-East China.

The scientists found a nesting behavior previously unknown in the entire animal kingdom: in over 70 nests they found an outer vestibular cell filled with dead ants. The species constructing these ant-filled vestibular cell was so far unknown to science and was described in the same study as the ‘Bone-house Wasp’ (Deuteragenia ossarium), after graveyard bone-houses or ossuaries. The scientists also found lower parasitism rates in “Bone-house” nests than in nests of similar cavity-nesting wasps. The authors suggest that D. ossarium nests are less vulnerable to natural enemies, potentially supporting the outer cell’s role in defense, which most likely involves chemical cues emanating from the dead ants used as nest-building material.

Dr. Staab added, “Our discovery demonstrates in an impressive way, what fascinating strategies of offspring-protection have evolved in the animal kingdom.”

Story Source:

The above story is based on materials provided by PLOS. Note: Materials may be edited for content and length.

Agriculture and Food News — ScienceDaily

Researching an endangered relationship: Bee species and their search for the flowering plants

The timing has been beautifully choreographed by nature. Rising spring temperatures prompt many bee species to begin their search for the flowering plants they depend on for food — and which they propagate through pollination. But what would happen if this vital, mutually beneficial relationship goes out of synch due to climate change? That’s what Assistant Professor of Biology Daniel Bunker and PhD candidate Caroline DeVan intend to determine with the help of a $ 150,000 grant from the National Science Foundation.

According to Bunker and DeVan, the consequences could be dire if this relationship unravels as a result of global climate change, consequences that include poor crop pollination and lower yields. In one troubling scenario, the pollinating bees may respond strongly to climate warming and emerge earlier in the growing season, while their preferred flowers respond less strongly and emerge later. Such a mismatch in timing could severely impact both bees and plants, and the productivity of many agricultural crops.

A local outdoor laboratory

DeVan became interested in climate change and the ecological role of bees after majoring in environmental studies and ecology at the University of Tennessee. “I find bees really interesting, and there are a lot of good questions that haven’t been asked,” she says. Pursuing her PhD in biology at NJIT has given her the opportunity to ask some critical questions and to work with Bunker, who is also very much interested in researching the ecological interdependence between plants and other organisms.

Looking at areas relatively close to NJIT that might be suitable as research sites, DeVan found that Morristown National Historical Park at Jockey Hollow has a substantial bee community — including cavity-nesting bees that forage among various flowering trees as well the “understory” plants beneath the trees. Unlike social bee species, such as honey bees, cavity-nesting bees lead solitary lives in the wild, pollinating many types of flowering trees as they search for food. In some parts of the country, orchard owners provide a hospitable nesting environment to encourage pollinating visits to almond, apple, cherry and other types of fruit trees.

The Morristown site also is appealing because it is a temperate forest, with a comparatively narrow window of time when the bees emerge in the spring and the trees leaf out. In addition, Morristown is part of the Northeast Temperate Network (NETN) established by the U.S. National Park Service to monitor ecological conditions in 12 parks located in seven northeastern states as well as six more states traversed by the Appalachian National Scenic Trail. Working at a NETN site enables DeVan and Bunker to integrate their data into the network’s larger ecological picture.

“We realized that Morristown could give us a really nice model system for looking at how bees and plants might respond differently to the effects of climate change,” Bunker says. He explains that the primary experimental focus is on the bees since their activity is influenced mainly by temperature, whereas plants respond to changes in the length of the day, the photoperiod, along with temperature. And the cavity-nesting bees at Morristown are especially sensitive to spring temperature changes.

Out and about early

To enlist the Morristown bees in their work, the researchers place nesting boxes they have built near 28 NETN forest-monitoring plots in the park. Adult bees create the nests. The nests have several cells with an egg in each one that metamorphosizes — like butterflies do — through the summer. By fall they are adults in their cocoons, where they overwinter. The initial phase of the program that Bunker and DeVan have initiated with the help of other NJIT colleagues and students involves waking the bees from winter dormancy earlier than usual during the spring by gently warming the boxes.

At this point, the researchers are still fine-tuning their experimental techniques, which include affixing micro-tags to the backs of the bees while they are still dormant in their cocoons. A video camera placed at each nest will allow building a database of the bees’ response to manipulated changes in their natural schedule, and how their well-being might be affected by corresponding disruptions caused by climate change.

The tags on the bees, a special variant of the widely used Quick Response “QR” code, will make it possible to monitor individual bees using computer-assisted image recognition, which is being developed under the lead of Associate Professor of Biology Gareth Russell. Physical examination of pollen in the nests also is expected to yield information about the food sources the bees visit, and analysis of the ratio of females to males to provide indications about how temperature variation may affect reproduction.

Agricultural impact

This effort could help to answer key questions about the possible impact of climate change on agriculture. At large and foraging for food before their normal sources are available, bees may not be able to adapt. DeVan emphasizes that this could devastate the cycle of plant pollination and reproduction. Or bees may adapt by feeding on different plants that flower earlier. While this could be a positive sign that bees are adaptable, it also may mean they are feeding on less nutritious plants, which could have a deleterious impact on bee populations.

For the solitary cavity-nesting bees, starting to forage earlier because they are out of synch with the flowering of their food sources could keep them away from their nests for longer periods. This, too, presents a potential threat. It may give flies, wasps and other predators greater opportunities to attack undefended eggs and larvae. As a result, it may be necessary to devise new strategies for protecting and managing these vital pollinators.

The data that Bunker and DeVan anticipate collecting over the next few years could confirm a disturbing possibility — that the critical relationship between temperature-sensitive bees and the plants they pollinate is in danger. Yet they may find that pollinators such as the bees at Morristown can adapt in ways that do not seriously undermine their role in pollination, and by implication in agricultural production. Whatever the research reveals, it will shed additional light on the relationship between bees and plants — and on one of the most important connections that humans have with nature.

Agriculture and Food News — ScienceDaily

Researching an endangered relationship: Bee species and their search for the flowering plants

The timing has been beautifully choreographed by nature. Rising spring temperatures prompt many bee species to begin their search for the flowering plants they depend on for food — and which they propagate through pollination. But what would happen if this vital, mutually beneficial relationship goes out of synch due to climate change? That’s what Assistant Professor of Biology Daniel Bunker and PhD candidate Caroline DeVan intend to determine with the help of a $ 150,000 grant from the National Science Foundation.

According to Bunker and DeVan, the consequences could be dire if this relationship unravels as a result of global climate change, consequences that include poor crop pollination and lower yields. In one troubling scenario, the pollinating bees may respond strongly to climate warming and emerge earlier in the growing season, while their preferred flowers respond less strongly and emerge later. Such a mismatch in timing could severely impact both bees and plants, and the productivity of many agricultural crops.

A local outdoor laboratory

DeVan became interested in climate change and the ecological role of bees after majoring in environmental studies and ecology at the University of Tennessee. “I find bees really interesting, and there are a lot of good questions that haven’t been asked,” she says. Pursuing her PhD in biology at NJIT has given her the opportunity to ask some critical questions and to work with Bunker, who is also very much interested in researching the ecological interdependence between plants and other organisms.

Looking at areas relatively close to NJIT that might be suitable as research sites, DeVan found that Morristown National Historical Park at Jockey Hollow has a substantial bee community — including cavity-nesting bees that forage among various flowering trees as well the “understory” plants beneath the trees. Unlike social bee species, such as honey bees, cavity-nesting bees lead solitary lives in the wild, pollinating many types of flowering trees as they search for food. In some parts of the country, orchard owners provide a hospitable nesting environment to encourage pollinating visits to almond, apple, cherry and other types of fruit trees.

The Morristown site also is appealing because it is a temperate forest, with a comparatively narrow window of time when the bees emerge in the spring and the trees leaf out. In addition, Morristown is part of the Northeast Temperate Network (NETN) established by the U.S. National Park Service to monitor ecological conditions in 12 parks located in seven northeastern states as well as six more states traversed by the Appalachian National Scenic Trail. Working at a NETN site enables DeVan and Bunker to integrate their data into the network’s larger ecological picture.

“We realized that Morristown could give us a really nice model system for looking at how bees and plants might respond differently to the effects of climate change,” Bunker says. He explains that the primary experimental focus is on the bees since their activity is influenced mainly by temperature, whereas plants respond to changes in the length of the day, the photoperiod, along with temperature. And the cavity-nesting bees at Morristown are especially sensitive to spring temperature changes.

Out and about early

To enlist the Morristown bees in their work, the researchers place nesting boxes they have built near 28 NETN forest-monitoring plots in the park. Adult bees create the nests. The nests have several cells with an egg in each one that metamorphosizes — like butterflies do — through the summer. By fall they are adults in their cocoons, where they overwinter. The initial phase of the program that Bunker and DeVan have initiated with the help of other NJIT colleagues and students involves waking the bees from winter dormancy earlier than usual during the spring by gently warming the boxes.

At this point, the researchers are still fine-tuning their experimental techniques, which include affixing micro-tags to the backs of the bees while they are still dormant in their cocoons. A video camera placed at each nest will allow building a database of the bees’ response to manipulated changes in their natural schedule, and how their well-being might be affected by corresponding disruptions caused by climate change.

The tags on the bees, a special variant of the widely used Quick Response “QR” code, will make it possible to monitor individual bees using computer-assisted image recognition, which is being developed under the lead of Associate Professor of Biology Gareth Russell. Physical examination of pollen in the nests also is expected to yield information about the food sources the bees visit, and analysis of the ratio of females to males to provide indications about how temperature variation may affect reproduction.

Agricultural impact

This effort could help to answer key questions about the possible impact of climate change on agriculture. At large and foraging for food before their normal sources are available, bees may not be able to adapt. DeVan emphasizes that this could devastate the cycle of plant pollination and reproduction. Or bees may adapt by feeding on different plants that flower earlier. While this could be a positive sign that bees are adaptable, it also may mean they are feeding on less nutritious plants, which could have a deleterious impact on bee populations.

For the solitary cavity-nesting bees, starting to forage earlier because they are out of synch with the flowering of their food sources could keep them away from their nests for longer periods. This, too, presents a potential threat. It may give flies, wasps and other predators greater opportunities to attack undefended eggs and larvae. As a result, it may be necessary to devise new strategies for protecting and managing these vital pollinators.

The data that Bunker and DeVan anticipate collecting over the next few years could confirm a disturbing possibility — that the critical relationship between temperature-sensitive bees and the plants they pollinate is in danger. Yet they may find that pollinators such as the bees at Morristown can adapt in ways that do not seriously undermine their role in pollination, and by implication in agricultural production. Whatever the research reveals, it will shed additional light on the relationship between bees and plants — and on one of the most important connections that humans have with nature.

Agriculture and Food News — ScienceDaily

EU must take urgent action on invasive species, experts urge

The EU must take urgent action to halt the spread of invasive species that are threatening native plants and animals across Europe, according to a scientist from Queen’s University Belfast.

The threats posed by these species cost an estimated €12 billion each year across Europe. Professor Jaimie Dick, from the Institute for Global Food Security at Queen’s School of Biological Sciences, is calling on the EU to commit long-term investment in a European-wide strategy to manage the problem.

Invasive species are considered to be among the major threats to native biodiversity in Europe. The call to action follows the publication of a paper Tackling Invasive Alien Species in Europe: the Top 20 Issues‘, in the peer-reviewed journal Management of Biological Invasions. The report’s authors say it should inform future EU policy for managing invasive species.

The paper resulted from an international meeting of invasive species experts who gathered in Galway (Ireland) last year to identify the critical issues for tackling invasive species in Europe. The Freshwater Invasives: Networking for Strategy (FINS) conference was led by Inland Fisheries Ireland, Queen’s, and the Institute of Technology, Sligo. It brought together more than 150 scientists, academics, policy makers and politicians with the aim of informing impending EU legislation on alien species.

Professor Dick said: “Alien plant and animal species cause environmental, economic and social damage across Europe, and their rate of invasion is set to increase in the coming years. The EU has formulated a comprehensive plan to address the threats posed by these species, but adequate resourcing by the EU and Member States, in terms of funding, staff and equipment, will be crucial in ensuring this plan is put into action.

“Invasive species cost an estimated €12 billion each year across Europe, including around €261 million on the island of Ireland and £1.7 billion in Great Britain. Their impact ranges from upsetting native ecosystems, to damaging the physical environment and even threatening human and animal health; hence the cost to agriculture, fisheries and forestry, as well as the expense of control and eradication programmes.

“The existing haphazard, fragmented approach from EU countries, characterised by communication breakdowns and insufficient resources, will not suffice if we are to protect our ecosystems against these invaders. The EU must ensure sufficient funding to achieve its goal of long-term, coherent, sustainable action to manage invasive species. Through the FINS conference, 20 issues that will be critical to the success of any EU strategy have now been identified. It is vital that EU decision-makers consider these issues when formulating their plans and allocating resource.

“Among the 20 issues identified is the need to raise awareness of biosecurity across Europe and the implementation of European-wide legislation for this; the dedication of resources for the long-term management of invasive species; the development of new technology to detect new invasives, and early warning systems to alert EU states to their spread; new European-wide risk assessment methods; emergency powers to eradicate alien species once they become established; and effective communications to raise awareness of invasive species, so the public will know what to look for and how to report it.”

Professor Jaimie Dick and Queen’s PhD student Jenny Barbour were key organisers of the FINS conference, which was called specifically with the aim of assessing the current position regarding invasive alien species in Europe. Experts from the UK and Ireland, and across North America, Europe, Africa and Asia joined forces to prioritise the key issues for the management of invasive species.

Story Source:

The above story is based on materials provided by Queen’s University, Belfast. Note: Materials may be edited for content and length.

Agriculture and Food News — ScienceDaily

Crop species may be more vulnerable to climate change than we thought

A new study by a Wits University scientist has overturned a long-standing hypothesis about plant speciation (the formation of new and distinct species in the course of evolution), suggesting that agricultural crops could be more vulnerable to climate change than was previously thought.

Unlike humans and most other animals, plants can tolerate multiple copies of their genes — in fact some plants, called polyploids, can have more than 50 duplicates of their genomes in every cell. Scientists used to think that these extra genomes helped polyploids survive in new and extreme environments, like the tropics or the Arctic, promoting the establishment of new species.

However, when Dr Kelsey Glennon of the Wits School of Animal, Plant and Environmental Sciences and a team of international collaborators tested this long-standing hypothesis, they found that, more often than not, polyploids shared the same habitats as their close relatives with normal genome sizes.

“This means that environmental factors do not play a large role in the establishment of new plant species and that maybe other factors, like the ability to spread your seeds to new locations with similar habitats, are more important,” said Glennon.

“This study has implications for agriculture and climate change because all of our important crops are polyploids and they might not be much better at adapting to changing climate than their wild relatives if they live in similar climates.”

Glennon’s study also provides an alternative explanation for why plants are so diverse in places like the Cape where the climate has been stable for hundreds of thousands of years. Although her study examined plant species from North America and Europe only, she is looking forward to testing her hypotheses using South African plants.

Glennon’s paper has been published in Ecology Letters.

Story Source:

The above story is based on materials provided by Wits University. Note: Materials may be edited for content and length.

Agriculture and Food News — ScienceDaily

New plant species a microcosm of biodiversity

Biologists working in the Andes mountains of Ecuador have described a new plant species, a wild relative of black pepper, that is in itself a mini biodiversity hotspot. The new species, Piper kelleyi, is the sole home of an estimated 40-50 insect species, most of which are entirely dependent on this plant species for survival. This discovery is part of a larger project which focuses on the influence of plant-produced chemical compounds on biodiversity.

The study was published in the open access journal PhytoKeys.

The chemical compounds produced by plants are source of plants’ unique flavors, aromas, and colors. What’s less appreciated is that these compounds often have important medicinal or toxic properties, and are the plant’s natural way to resist pesky herbivores. Black pepper and its wild relatives produce a wide diversity of chemical compounds, many of which are known to be biologically active (in fact, several compounds from the new species are currently under evaluation, and show promise as possible anti-cancer drugs). These compounds are known to deter most herbivores, but a certain group of caterpillars has been able to overcome their toxicity and, as a result, most species of the genus feed only on a single species of wild black pepper. To make matters more complex, each of these caterpillars typically has one to several predatory wasp and/or fly species that attack only that caterpillar species.

Our team of scientists has made nearly 30,000 observations of over 100 black pepper relatives over 20+ years, and the new plant species described here supports the largest number of specialized caterpillar and predator species recorded for species in the black pepper family to date. Many of these insect species were discovered as a result of our investigations and are new to science (many remain unnamed). Piper kelleyi supports an estimated 40-50 species of specialized herbivores and predators, which makes this newly described plant species, in itself, a veritable biodiversity hotspot. Are there any vertebrate species that depend on this plant? Nobody knows, but relatives of black pepper are often important food sources for vertebrates, such as bats and birds, that specialize on their fruits or feed on associated insects.

This finding has conservation implications as well. The insect species that make up this unusually large assemblage are, for the most part, entirely dependent on the new plant species and, if the plant were to disappear, all of its associated animal species would too.

Evidence suggests that the unique compounds produced by a plant species, or the unique combination of these compounds, help drive the evolution of biological diversity, not only among the herbivores that feed directly on the plants, but among higher trophic levels as well. The discovery of our new species, along with its large cohort of dependent insects, lends considerable support to the hypothesis that a suite of new species of herbivores and predators of those herbivores evolves in response to the evolution of novel plant-produced chemical compounds.

Story Source:

The above story is based on materials provided by Pensoft Publishers. The original story is licensed under a Creative Commons License. Note: Materials may be edited for content and length.

Agriculture and Food News — ScienceDaily

New species of fascinating opportunistic shelter using leaf beetles

Sep. 27, 2013 — Previously unknown to science leaf beetles modify and use as shelter the holes in leaves of their host plants made by other beetles.

Many animals construct homes or shelters to escape from biological and physical hostilities. Birds, spiders, termites, ants, bees and wasps are the most famous animal architects. As shelter construction requires considerable investment of resources and time, builders tend to minimize the cost of building while maximizing the benefits.

Builders are rather uncommon among adult leaf beetles though young ones of certain species use own feces to construct a defensive shield. Two closely related, hitherto unknown species of tiny southern Indian leaf beetles, only slightly larger than the size of a pin-head, and their clever way of using and modifying low cost shelters, is described in the open access journal ZooKeys. These beetles make use of holes pre-formed by larger leaf feeding beetles on the leaves of their host trees thus reducing cost of the shelter just like some birds that nest in existing cavities produced by primary cavity nesters, such as woodpeckers.

The beetles also use artificially made holes to construct hideouts called “leaf hole shelters.” As the shape and size of the hole were not exactly in tune with the requirements of the beetle, they resized the hole by partitioning with a wall constructed with own fecal pellets. Use of feces by adult leaf beetles for construction of shelters is being described for the first time, with these two new southern Indian species namely Orthaltica eugenia and Orthaltica terminalia. The beetles are named after their host trees, common in jungles of the Western Ghats Mountains, which is a globally recognized hot spot of biodiversity.

ScienceDaily: Agriculture and Food News

Microbes facilitate the persistence, spread of invasive plant species by changing soil chemistry

Sep. 26, 2013 — Invasive species are among the world’s greatest threats to native species and biodiversity. Once invasive plants become established, they can alter soil chemistry and shift nutrient cycling in an ecosystem. This can have important impacts not only on plant composition, diversity, and succession within a community, but also in the cycling of critical elements like carbon and nitrogen on a larger, potentially even global, scale. Clearly, both native and exotic plants form intimate relationships with bacteria in the soil that facilitate the extraction and conversion of elements to biologically usable forms. Yet an unanswered question with regard to plant invasions remains: could the changes in soil biogeochemistry be due to an advantage that invasive plants get from interacting with their microbiome?

When alien species invade and take over communities, they may not come alone — many plant species are host to a whole suite of microorganisms that not only live in plant cells, but also in the soil surrounding the plants’ roots. These microbes form close, often mutualistic, associations with their plant hosts. Some convert atmospheric nitrogen into bioavailable forms that are then exchanged for carbon from the plant. Bioavailable nitrogen is frequently limiting in soils, yet many invaded ecosystems have more carbon and nitrogen in plant tissues and soils compared with systems dominated by native plants. Since changes in the soil nitrogen cycle are driven by microbes, could bacteria associated with invasive species not only be responsible for the observed changes in soil nutrient concentrations, but also for enabling the continued growth and persistence of the invader species?

These were the kinds of questions that started percolating for Marnie Rout (University of North Texas Health Science Center) after she drove by a remnant tallgrass prairie in North Central Texas as a beginning graduate student. She was particularly struck by the obvious and drastic changes the native prairie was undergoing due to the invasion of an exotic grass.

“It literally looked like someone had drawn a line down the field,” Rout explained. “On one side was the native prairie, the other side had this towering monoculture of invasive Sorghum. The plant looked like it was invading in a military fashion, forming this distinct line that was clearly visible.”

Subsequent literature searches led to the discovery that sugar cane, an agriculturally important crop, is a nitrogen fixer that contains bacterial endophytes, and Rout became curious if the microbes she and her colleague Tom Chrzanowski (The University of Texas Arlington) discovered in invasive Sorghum might be providing similar benefits to this invasive plant.

Rout combined forces with colleagues from The University of Montana, The University of Texas Arlington, and University of Washington to investigate whether the differences in soil nutrient concentrations found in an invaded prairie could be due to metabolic processes of the bacterial microbiome associated with the invasive grass, and to determine whether these microbial agents facilitate the perpetuation and spread of this invasive grass. They published their findings in a Special Section in the American Journal of Botany on Rhizosphere Interactions: The Root Biome.

“Things attributed to plant-plant interactions like competition and facilitation are likely under more microbial regulation than we have been giving them credit,” Rout commented. “Studying disruptions to ecosystems like those seen in plant invasions provides a window into something — specifically the process of co-evolution — that we normally don’t get to observe in a single human lifetime.”

Indeed, the alarming rate — almost 0.5 meters a year — at which the invasive grass Sorghum halepense has invaded the tallgrass prairie, formerly dominated by the native little bluestem (Schizachyrium scoparium), over the last 25 years, and the complete dominance of that invasive was the ideal situation in which Rout could test her ideas.

Rout and colleagues first confirmed that the invaded soils of the prairie did indeed have higher levels of nitrogen, phosphorous, and iron-derived chemicals compared with the non-invaded prairie soils still dominated by native plants. They then tested whether the interactions between the dominant invasive grass and the soil biota could be responsible for the observed changes in the soil nutrient concentrations.

By isolating five bacterial strains of endophytes found inside S. halepense rhizomes (subterranean stems used for storage and vegetative reproduction) and growing them in the lab in different mixtures of substrates, the authors determined that these microbes were able to fix and mobilize nitrogen, phosphorus, and iron. All three are important elements associated with plant growth; however, some were produced in excess of what would be needed for plant growth. Indeed, perhaps somewhat alarmingly, the amount of iron that was produced reached levels that are toxic to many crops — and may even inhibit establishment of native species.

Furthermore, the authors were able to show that not only can this invasive plant acquire microbes from the environment, but that it is also capable of passing them on to the next generation via seeds. Using a sophisticated series of intricate experiments involving growing seedlings from surface sterilized seeds in nitrogen- deprived or nitrogen-augmented soils and slurries with different suites of soil microbes, Rout and colleagues showed that these microbes enabled the grass to produce 5-fold increases in rhizomes, a primary mechanism driving invasions of this species.

These findings give us a new understanding of how an invasive plant can acquisition soil biota to its own advantage, altering the environment and changing the ecosystem in the process. By acquiring soil bacteria, S. halepense increases the bioavailable nitrogen and phosphorus in the soil, and has increased rhizome production and aboveground biomass, which in turn facilitates its spread and establishment. Moreover, these changes to the soil chemistry not only increase the competitive edge of this invasive species, but also can inhibit or eliminate the existing native species.

“This research shows that macro-scale observations, such as plant trait expression, and ecosystem functions like nutrient cycling, are more intimately connected to micro-scale influences than we might expect,” summarizes Rout.

Rout’s fascination with bacterial endophytes continues; she is currently exploring them from a genetic perspective to better understand the complex communication between the microbiome and the plant.

“With the growing human population and concerns for meeting the global food crisis in the coming decades, invasive plants and their microbiomes might turn out to be useful for enhancing crop yields.”

“The root microbiome is as important to plant health and agricultural productivity,” she concludes, “as the human microbiome is to human health.”

ScienceDaily: Agriculture and Food News

Bees ‘betray’ their flowers when pollinator species decline

July 22, 2013 — Remove even one bumblebee species from an ecosystem and the impact is swift and clear: Their floral “sweethearts” produce significantly fewer seeds, a new study finds.

The study, to be published by the Proceedings of the National Academy of Sciences, focused on the interactions between bumblebees and larkspur wildflowers in Colorado’s Rocky Mountains. The results show how reduced competition among pollinators disrupts floral fidelity, or specialization, among the remaining bees in the system, leading to less successful plant reproduction.

“We found that these wildflowers produce one-third fewer seeds in the absence of just one bumblebee species,” says Emory University ecologist Berry Brosi, who led the study. “That’s alarming, and suggests that global declines in pollinators could have a bigger impact on flowering plants and food crops than was previously realized.”

The National Science Foundation (NSF) funded the study, co-authored by ecologist Heather Briggs of the University of California-Santa Cruz.

About 90 percent of plants need animals, mostly insects, to transfer pollen between them so that they can fertilize and reproduce. Bees are by far the most important pollinators worldwide and have co-evolved with the floral resources they need for nutrition.

During the past decade, however, scientists have reported dramatic declines in populations of some bee species, sparking research into the potential impact of such declines.

Some studies have indicated that plants can tolerate losing most pollinator species in an ecosystem as long as other pollinators remain to take up the slack. Those studies, however, were based on theoretical computer modeling.

Brosi and Briggs were curious whether this theoretical resilience would hold up in real-life scenarios. Their team conducted field experiments to learn how the removal of a single pollinator species would affect the plant-pollinator relationship.

“Most pollinators visit several plant species over their lifetime, but often they will display what we call floral fidelity over shorter time periods,” Brosi explains. “They’ll tend to focus on one plant while it’s in bloom, then a few weeks later move on to the next species in bloom. You might think of them as serial monogamists.”

Floral fidelity clearly benefits plants, because a pollinator visit will only lead to plant reproduction when the pollinator is carrying pollen from the same plant species. “When bees are promiscuous, visiting plants of more than one species during a single foraging session, they are much less effective as pollinators,” Briggs says.

The researchers conducted their experiments at the Rocky Mountain Biological Laboratory near Crested Butte, Colorado. Located at 9,500 feet, the facility’s subalpine meadows are too high for honeybees, but they are buzzing during the summer months with bumblebees. The experiments focused on the interactions of the insects with larkspurs, dark-purple wildflowers that are visited by 10 of the of the 11 bumblebee species there.

The researchers studied a series of 20-meter square wildflower plots, evaluating each one in both a control state, left in its natural condition, and in a manipulated state, in which they used nets to remove the bumblebees of just one species.

The researchers then observed the bumblebee behavior in both the controlled plots and the manipulated plots. “We’d literally follow around the bumblebees as they foraged,” Briggs says. “It’s challenging because the bees can fly pretty fast.”

Sometimes the researchers could only record between five and 10 movements, while in other cases they could follow the bees to 100 or more flowers.

“Running around after bumblebees in these beautiful wildflower meadows was one of the most fun parts of the research,” Brosi says. Much of this “bee team” was made up of Emory undergraduate students, funded by the college’s Scholarly Inquiry and Research at Emory (SIRE) grants and NSF support via the Research Experience for Undergraduates (REU) program.

The Rocky Mountain Biological Laboratory is exacting about using non-destructive methodologies so that researchers don’t have a negative impact on the bumblebee populations. “When we caught bees to remove target species from the system, or to swab their bodies for pollen, we released them unharmed when our experiments were over,” Brosi says. “They’re very robust little creatures.”

No researchers were harmed either, he adds. “Stings were very uncommon during the experiments. Bumblebees are quite gentle on the whole.”

Across the steps of the pollination process, from patterns of bumblebee visits to plants, to picking up pollen, to seed production, the researchers saw a cascading effect of removing one bee species. While about 78 percent of the bumblebees in the control groups were faithful to a single species of flower, only 66 percent of the bumblebees in the manipulated groups showed such floral fidelity. The reduced fidelity in manipulated plots meant that bees in the manipulated groups carried more different types of pollen on their bodies than those in the control groups.

These changes had direct implications for plant reproduction: Larkspurs produced about one-third fewer seeds when one of the bumblebee species was removed, compared to the larkspurs in the control groups.

“The small change in the level of competition made the remaining bees more likely to ‘cheat’ on the larkspur,” Briggs says.

While previous research has shown how competition drives specialization within a species, the bumblebee study is one of the first to link this mechanism back to the broader functioning of an ecosystem.

“Our work shows why biodiversity may be key to conservation of an entire ecosystem,” Brosi says. “It has the potential to open a whole new set of studies into the functional implications of interspecies interactions.”

ScienceDaily: Agriculture and Food News

Why crop rotation works: Change in crop species causes shift in soil microbes

July 18, 2013 — Crop rotation has been used since Roman times to improve plant nutrition and to control the spread of disease. A new study to be published in Nature’s The ISME Journal reveals the profound effect it has on enriching soil with bacteria, fungi and protozoa.

“Changing the crop species massively changes the content of microbes in the soil, which in turn helps the plant to acquire nutrients, regulate growth and protect itself against pests and diseases, boosting yield,” said Professor Philip Poole from the John Innes Centre.

Soil was collected from a field near Norwich and planted with wheat, oats and peas. After growing wheat, it remained largely unchanged and the microbes in it were mostly bacteria. However, growing oat and pea in the same sample caused a huge shift towards protozoa and nematode worms. Soil grown with peas was highly enriched for fungi.

“The soil around the roots was similar before and after growing wheat, but peas and oats re-set of the diversity of microbes,” said Professor Poole.

All organisms on our planet can be divided between prokaryotes (which include bacteria) and eukaryotes (which include humans, plants and animals as well as fungi). After only four weeks of growth, the soil surrounding wheat contained about 3% eukaryotes. This went up to 12-15% for oat and pea. The change of balance is likely to be even more marked in the field where crops are grown for months rather than weeks.

Analysis has previously relied on amplifying DNA samples. This limits scientists to analysing one taxonomic group at a time such as bacteria. It also means that everything present in that group is analysed rather than what is playing an active role. Every gram of soil contains over 50,000 species of bacteria so the task is enormous.

There are relatively fewer actively expressed genes, or RNA. It is now possible to sequence RNA across kingdoms so a full snapshot can be taken of the active bacteria, fungi, protozoa and other microbes in the soil. The research was carried out in collaboration with the University of East Anglia and The Genome Analysis Centre on Norwich Research Park.

“By sequencing RNA, we can look at the big picture of active microbes in the soil,” said PhD student Tom Turner from the John Innes Centre.

“This also allows us to work out what they are doing there, including how they might be helping the plants out.”

“Our work helps explain the experience of farmers in the field,” said Professor Poole.

“The best seed needs to be combined with the best agronomic practices to get the full potential benefits.”

“While continued planting of one species in monoculture pulls the soil in one direction, rotating to a different one benefits soil health.”

Seeds can be inoculated with bacteria before planting out, just like humans taking a dose of friendly bacteria. But this does not achieve the diversity or quantity of microbes found in this study.

The scientists also grew an oat variety unable to produce normal levels of avenacin, a compound that protects roots from fungal pathogens. They expected the soil to contain higher levels of fungi as a result, but instead found it contained a greater diversity of other eukaryotes such as protozoa.

The findings of the study could be used to develop plant varieties that encourage beneficial microbes in the soil. John Innes Centre scientists are already investigating the possibility of engineering cereal crops able to associate with the nitrogen-fixing bacteria normally associated with peas.

“Small changes in plant genotype can have complex and unexpected effects on soil microbes surrounding the roots,” said Professor Poole.

“Scientists, breeders and farmers can make the most of these effects not only with what they grow but how they grow it.”

ScienceDaily: Agriculture and Food News