A new study reveals a complex interplay between soil fungi and tree roots that could be the cause of rare-species advantage. The researchers found that the type of beneficial soil fungi living around tree roots in a subtropical forest in…
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As their Latin name indicates, pineapples are truly “excellent fruits”—and thanks to a freshly completed genome sequencing project, researchers have gained a new understanding of how human agriculture has shaped the evolution of this and other crops.
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Researchers have discovered a new function of one of the plant’s proteins – BAG4. In their study, they show that this protein takes part in regulating the plant’s breathability, the transporting of potassium to occlusive cells and, therefore, the opening…
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A team of scientists with two disparate sets of expertise - in plant biology and protein structural chemistry - have unraveled the atomic basis of how optimal numbers of stomata are made in leaves.
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An international team succeeded in assembling the first sequence of the pea genome. This study will, in addition to increasing knowledge of this genome compared to that of other legumes, help to improve traits of interest for peas, such as…
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Scientists identified significant new chromosomal regions for wheat yield and disease resistance, which will speed up global breeding efforts.
Using the full wheat genome map published in 2018, combined with data from field testing of wheat breeding lines in multiple countries, an international team of scientists has identified significant new chromosomal regions for wheat yield and disease resistance and created a freely-available collection of genetic information and markers for more than 40,000 wheat lines.
Reported in Nature Genetics, the results will speed up global efforts to breed more productive and climate-resilient varieties of bread wheat, a critical crop for world food security that is under threat from rising temperatures, rapidly-evolving fungal pathogens, and more frequent droughts, according to Philomin Juliana, wheat scientist at the International Maize and Wheat Improvement Center (CIMMYT) and first author of the new study.
“This work directly connects the wheat genome reference map with wheat lines and extensive field data from CIMMYT’s global wheat breeding network,” said Juliana. “That network in turn links to over 200 breeding programs and research centers worldwide and contributes to yield and other key traits in varieties sown on nearly half the world’s wheat lands.”
The staple food for more than 2.5 billion people, wheat provides 20% of human dietary calories and protein worldwide and is critical for the nutrition and food security of hundreds of millions of poor persons in regions such as North Africa and South Asia.
“Farmers and societies today face new challenges to feed rising and rapidly-urbanizing populations, and wheat epitomizes the issues,” said Ravi Singh, CIMMYT wheat breeder and corresponding author of the study. “Higher temperatures are holding back yields in major wheat-growing areas, extreme weather events are common, crop diseases are spreading and becoming more virulent, and soil and water are being depleted.”
Juliana said the study results help pave the way to apply genomic selection, an approach that has transformed dairy cow husbandry, for more efficient wheat breeding.
“Molecular markers are getting cheaper to use; meanwhile, it’s very costly to do field testing and selection involving many thousands of wheat plants over successive generations,” Juliana said. “Genome-wide marker-based selection can help breeders to precisely identify good lines in early breeding generations and to test plantlets in greenhouses, thereby complementing and streamlining field testing.”
The new study found that genomic selection could be particularly effective in breeding for wheat end-use quality and for resistance to stem rust disease, whose causal pathogen has been evolving and spreading in the form of highly-virulent new races.
The new study also documents the effectiveness of the global public breeding efforts by CIMMYT and partners, showing that improved wheat varieties from this work have accumulated multiple gene variants that favor higher yields, according to Hans-Joachim Braun, director of CIMMYT’s global wheat program.
“This international collaboration, which is the world’s largest publicly-funded wheat breeding program, benefits farmers worldwide and offers high-quality wheat lines that are released directly to farmers in countries, such as Afghanistan, that are unable to run a full-fledged wheat breeding program,”
Braun explained.
The study results are expected to support future gene discovery, molecular breeding, and gene editing in wheat, Braun said.
Together with more resource-efficient cropping systems, high-yielding and climate-resilient wheat varieties will constitute a key component of the sustainable intensification of food production described in Strategy 3 of the recent EAT-Lancet Commission recommendations to transform the global food system. Large-scale genomics will play a key role in developing these varieties and staying ahead of climate- and disease-related threats to food security.
Read the paper: Nature Genetics
Article source: CIMMYT
Image: Apollo Habtamu/CIMMYT
Species of daisy that close their flowers at night, produce colour in their exposed lower petals that makes them harder to spot for herbivores, reducing herbivory rates of flowers. The findings are presented in the British Ecological Society journal Functional Ecology.
Researchers from Stellenbosch University, South Africa found that tortoises, one of the main herbivores of the daisies, were unable to distinguish the lower petal surfaces against a green leaf background. Tortoises prefer to eat protein-rich flowers over leaves, but when confronted with closed flowers, they showed no preference between them.
When the researchers modelled the colours of the lower petal surfaces in the vision of other herbivores, they also found these colours to be indistinguishable from leaves.
In contrast, species of daisy that do not close at night produced the same colouration on their lower petals as the upper petals exposed to pollinators.
Plants face an evolutionary conflict between having flowers that attract pollinators while avoiding herbivores. Often plants defend themselves chemically, but this can have adverse effects on pollination.
“When plants defend their flowers chemically, the pollination interactions can be negatively influenced. Our study shows a novel way in which flowers can avoid herbivores, without compromising pollination interactions.
– says Dr. Jurene Kemp, lead author of the study.
“These flowers can potentially circumvent the conflict of attracting both pollinators and herbivores by producing attractive colours on the surfaces that are exposed to pollinators (when flowers are open) and cryptic colours that are exposed when herbivores are active (when flowers are closed).”
In Namaqualand, South Africa, where the research took place, daises bloom annually in a spring flowering. This makes preserving flowers, responsible for reproduction, particularly important.
The researchers examined the colouration of 77 Asteraceae species, modelling how they appear in the visual systems of chameleons, horses and goats as proxies for tortoises and larger herbivores in the area, like springbok. They then tested the preferences of real tortoises with both open and closed flowers against leaf backgrounds.
Not all Asteraceae species that close their flowers had cryptically coloured lower petal surfaces, but in the experiments, the tortoises did not readily eat these flowers. Dr. Kemp said, “One interesting question would be to test whether non-cryptic flowers have chemical defences, and whether these chemical defences are absent in the cryptic flowers.”
On further research Dr. Kemp said “Unfortunately, we could only do this using one plant family in one botanical region, it would be great to see if other plant species also use colour to avoid herbivores.”
The researchers would also have liked to use larger herbivores such as springboks in their behavioural experiments, but Dr. Kemp adds that “this was practically not possible.”
Read the paper: Functional Ecology
Article source: British Ecological society Press Office
Image: Jurene Kemp
Picture a typical documentary scene on the evolution of life. It probably starts with little bugs in a murky, primordial soup. Eons of time zip by as bugs turn into fish, fish swim to land as their fins morph into limbs for crawling animals, which then stand up on two legs, to finally end up with walking humans.
The picture is very animal-centric. But what about plants? They also made the jump from water to land. Scientists think that green algae are their water-living ancestors, but we are not sure how the transition to land plants happened.
New research from Michigan State University, and published in the journal eLife, presents evidence that algae could have piggybacked on fungi to leave the water and to colonize the land, over 500 million years ago.
“Fungi are found all over the planet. They create symbiotic relationships with most land plants. That is one reason we think they were essential for evolution of life on land. But until now, we have not seen evidence of fungi internalizing living algae,” says Zhi-Yan Du, study co-author and member of the labs of Christoph Benning, and now, Gregory Bonito.
Researchers selected a strain of soil fungus and marine alga from old lineages, respectively Mortierella elongata and Nannochloropsis oceanica.
When grown together, both organisms form a strong relationship.
“Microscopy images show the algal cells aggregating around and attaching to fungal cells,” Du says. “The algal wall is slightly broken down, and its fibrous extensions appear to grab the surface of the fungus.”
Surprisingly, when they are grown together for a long time – around a month – some algal cells enter the fungal cells. Both organisms remain active and healthy in this relationship.
This is the first time scientists have seen fungi internalize a expand iconeukaryotic, photosynthetic organism. They call it a ‘photosynthetic mycelium’.
“Both organisms get additional benefits from being together,” Du says. “They exchange nutrients, with a likely net flow of carbon from alga to fungus, and a net flow of nitrogen in the other direction. Interestingly, the fungus needs physical contact with living algal cells to get nutrients. Algal cells don’t need physical contact or living fungus to benefit from the interaction. Fungal cells, dead or alive, release nutrients in their surroundings.”
“Even better, when nutrients are scarce, algal and fungal cells grown together fend off starvation by feeding each other. They do better than when they are grown separately.”
Perhaps this increased hardiness explains how algae survived the trek onto land.
“In nature, similar symbiotic events might be going on, more than we realize,” Du adds. “We now have a system to study how a expand iconphotosynthetic organism can live inside a non-photosynthetic one and how this symbiosis evolves and functions.”
Both organisms are biotech related strains because they produce high amounts of oil. Du is testing them as a platform to produce high-value compounds, such as biofuels or Omega 3 fatty acids.
“Because the two organisms are more resilient together, they might better survive the stresses of bioproduction,” Du says. “We could also lower the cost of harvesting algae, which is a large reason biofuel costs are still prohibitive.”
Read the paper: eLife
Article source: MSU-DOE Plant Research Laboratory
Image: Zhi-Yan Du, colored by Igor Houwat; from eLife
David Zilberman
Modified crops such as Golden Rice could have major benefits for people in developing nations. Image credit: IRRI Licensed under CC BY 2.0
By David Zilberman, Professor and Robinson Chair, Agriculture and Resource Economics, UC Berkeley
When I started working on agronomical issues in the 1970s, the most exciting technologies were related to water, machinery, and harvesting. Plant genetics seemed to be quite a boring enterprise. But as I became familiar with the Green Revolution, I realized the importance of plant research, and that the golden rule in agriculture is to find the optimal mixture between biotic and abiotic technologies. As an economist working on technology, I started to realize that the past fifty years have drastically changed the way plant sciences are done, and the potential and value of their product.
The discovery of the innerworkings of a cell, combined with the power of computers and precision tools, has changed medicine, but it has perhaps the potential to make an even bigger impact on plant sciences and agriculture. I have been working on the economics and policy aspects of agricultural biotechnology (see also Journal of Economic Perspectives). Despite the restrictions on genetically modified varieties, they increase yields and make food more affordable for the poor. They also reduce greenhouse gas emissions and actually improved human health (by reducing exposure to chemicals and aflatoxin). But biotechnologies have had limited impact because of regulations that limit their use mostly to feed and fiber crops, and the practical ban on use of GMOs in Europe and parts of Africa.
It’s clear that developing countries can be the major beneficiaries of these technologies. They can save billions of dollars and address severe health and malnourishment problems. Furthermore, applications of biotechnology on food crops can reduce food security problems and increase access to valuable fresh produce throughout the world. Modern biotechnology can provide tools to accelerate adaptation to climate change, and I am surprised that some of the organizations most aware of climate change don’t recognize the value of biotechnology to address it.
Plant science research has already made major achievements using traditional and advanced tools to provide better varieties and improve the global food situation in a world with a fast growing population. There is a large body of literature documenting the rate of return of research, and much of the achievements have been the development of new varieties. The literature suggests that public research that provided much of the benefit has been underfunded, and its funding is declining. Thus, plant research hasn’t reached its potential.
Thus far, applied research in plant sciences at many universities concentrate on grasses, like corn and wheat, but underemphasize trees and algae. One explanation to the emphasis on grasses is the immediate economic benefits they seem to provide. With all the modern tools of biology, the big challenges and some of the most radical and relevant knowledge can come from the study of trees and algae within the context of forest and oceans. Studies of these specimens will enhance our understanding of living systems, is crucially important from a macro-ecological perspective, and from a practical perspective of finding new materials, new foods and efficient sources of energy.
Poplar is one of the most commonly used trees in plant science research. Image credit: Walter Siegmund
I believe that society tends to underinvest in plant sciences, both because science is underfunded in general and because of the regulations of biotechnology that limit their use, as mentioned above. The contribution of plant scientists to address problems of climate change, deforestation, food security, and environmental quality are under-emphasized and under-recognized. This leads to less investment in this area, less contribution, and less student interest. But more investment in plant sciences may provide better understanding of their impact and how to regulate them, and provide more promising applications. So we are in a vicious cycle of over-regulation and under-funding that mostly hurt regions and populations that are vulnerable, and reduce our capabilities to deal with global changes.
To move forward, we need to have more enlightened regulations that will allow us to take advantage of this incredible science and big jolts in terms of support for research in plant sciences. Enlightened regulations would balance benefits and risks, reduce the cost of access to modern biotechnologies. They also would allow efficient and mutually beneficial transfer of knowledge and genetic materials across locations. Plant sciences is one discipline where the distribution of efforts across locations globally can be especially beneficial as we can learn about the performance of plant systems throughout the world. Therefore, investments in plant sciences should be distributed globally. For example, a major effort to raise funding for 100 Chairs of Plant Sciences around the world, especially in developing countries, will be a good start. It should be associated with support for student research, as well as forums the exchange of new ideas. And finally, new investments in arboretums and greenhouses.
Plant sciences have been providing humanity essential knowledge that enabled the growth and evolution of human civilization without much fanfare. New tools increase its potential and the excitement and value of research in these areas. Society needs to expand their support to plant sciences to enable it to flourish around the world, as well as enlightened regulation to gain benefits from the fruits of this research.
This blog has been reposted with permission from the MSU-DOE Plant Research Laboratory.
Unlike animals, plants can’t run away when things get bad. That can be the weather changing or a caterpillar starting to slowly munch on a leaf. Instead, they change themselves inside, using a complex system of hormones, to adapt to challenges.
Now, MSU-DOE Plant Research Laboratory scientists are connecting two plant defense systems to how these plants do photosynthesis. The study, conducted in the labs of Christoph Benning and Gregg Howe, is in the journal, The Plant Cell.
At the heart of this connection is the chloroplast, the engine of photosynthesis. It specializes in producing compounds that plants survive with. But plants have evolved ways to use it for other, completely unrelated purposes.
Their trick is to harvest their own chloroplasts’ protective membranes, made of lipids, the molecules found in fats and oils. Lipids have many uses, from making up cell boundaries, to being part of plant hormones, to storing energy.
If plants need lipids for some purpose other than serving as membranes, special proteins break down chloroplast membrane lipids. Then, the resulting products go to where they need to be for further processing.
For example, one such protein, breaks down lipids that end up in plant seed oil. Plant seed oil is both a basic food component and a precursor for biodiesel production.
Now, Kun (Kenny) Wang, a former Benning lab grad student, reports two more such chloroplast proteins with different purposes. Their lipid breakdown products help plants turn on their defense system against living pests and other herbivores. In turn, the proteins, PLIP2 and PLIP3, are themselves activated by another defense system against non-living threats.
Playing the telephone game inside plants
In a nutshell, the plant plays a version of the popular children’s game, Telephone, with itself. In the real game, players form a line. The first person whispers a message into the ear of the next person in the line, and so on, until the last player announces the message to the entire group.
In plants, defense systems and chloroplasts also pass along chemical messages down a line. Breaking it down:
- The plant senses non-living threats, like cold or drought, and indicates it through one hormone (ABA)
- This alarm triggers the two identified proteins to breakdown lipids from the chloroplast membrane
- The lipid products turn into another hormone (JA) which takes part in the insect defense system. Plant growth slows to a crawl. Energy goes to producing defensive chemicals.
“The cross-talk between defense systems has a purpose. For example, there is mounting evidence that plants facing drought are more vulnerable to caterpillar attacks,” Kenny says. “One can imagine plants evolving precautionary strategies for varied conditions. And the cross-talk helps plants form a comprehensive defense strategy.”
Kenny adds, “The chloroplast is amazing. We suspect its membrane lipids spur functions other than defense or oil production. That implies more Telephone games leading to different ends we don’t know yet. We have yet to properly examine that area.”
“Those functions could help us better understand plants and engineer them to be more resistant to complex stresses.”
Moving on to Harvard Medical School
Kenny recently got his PhD from the MSU Department of Biochemistry and Molecular Biology. He has just started a post-doc position in the Farese-Walther lab at Harvard Medical School.
“They look at lipid metabolism in mammals and have started a project connecting it with brain disease in humans,” Kenny says. “There is increasing evidence that problems with lipid metabolism in the brain might lead to dementia, Alzheimer’s, etc.”
“I benefited a lot from my time at MSU. The community is very successful here: the people are nice, and you have support from colleagues and facilities. Although we scientists should sometimes be independent in our work, we also need to interact with our communities. No matter how good you are, there is a limit to your impact as an individual. That is one of the lessons I applied when looking for my post-doc.”
Photo of the author, Kun (Kenny) Wang. By Kenny Wang
Read the original article here.
