Global Plant Council Blog

Plant Science for Global Challenges

Page 2 of 34

Taking the brakes off plant production: not so good after all

Reposted with kind permission from the MSU-DOE Plant Research Laboratory. Original article.

By: Igor Houwat, Atsuko Kanazawa, David Kramer

The need for speed: increasing plant yield is one way to increase food and fuel resources. But asking plants to simply do more of the usual is a strategy that can backfire. Photo by Romain Peli on Unsplash

When engineers want to speed something up, they look for the “pinch points”, the slowest steps in a system, and make them faster.

Say, you want more water to flow through your plumbing. You’d find the narrowest pipe and replace it with a bigger one.

Many labs are attempting this method with  photosynthesis, the process that plants and algae use to capture solar energy.

All of our food and most of our fuels have come from photosynthesis. As our population increases, we need more food and fuel, requiring that we improve the efficiency of photosynthesis.

But, Dr. Atsuko Kanazawa and the Kramer Lab are finding that, for biological systems, the “pinch point” method can potentially do more harm than good, because the pinch points are there for a reason!  So, how can this be done?

 

ATP synthase: an amazing biological nanomachine

Atsuko and her colleagues at the MSU-DOE Plant Research Laboratory (PRL) have been working on this problem for over 15 years. They have focused on a tiny machine in the  chloroplast called the  ATP synthase, a complex of proteins essential to storing solar energy in “high energy molecules” that power life on Earth.

That same ATP molecule and a very similar ATP synthase are both used by animals, including humans, to grow, maintain health, and move.

In plants, the ATP synthase happens to be one of the slowest process in photosynthesis, often limiting the amount of energy plants can store.

Photosynthetic systems trap sunlight energy that starts the reaction to move electrons forward in an assembly-line fashion to make useful energy compounds. The ATP synthase is one of the “pinch points” that slows the flow as needed, so plants stay healthy. In cfq, the absence of feedback leads to an electron pile up at PSI, and a crashed system. By MSU-DOE Plant Research Laboratory, except tornado graphic/CC0 Creative Commons

 

Kicking up the gears of plant production

Atsuko thought, if the ATP synthase is such an important pinch point, what happens if it were faster? Would it be better at photosynthesis and give us faster growing plants?

Years ago, she got her hands on a mutant plant, called cfq, from a colleague. “It had an ATP synthase that worked non-stop, without slowing down, which was a curious example to investigate. In fact, under controlled laboratory conditions – very mild and steady light, temperature, and water conditions – this mutant plant grew bigger than its wild cousin.”

But when the researchers grew the plant under the more varied conditions it experiences in real life, it suffered serious damage, nearly dying.

“In nature, light and temperature quality change all the time, whether through the passing hours, or the presence of cloud cover or winds that blow through the leaves,” she says.

 

Plants slow photosynthesis for a reason!

Recent innovations from the Kramer lab are enabling Atusko and her colleagues to probe into how real environmental conditions affect plant growth.

Atsuko’s research now shows that the slowness of the ATP synthase is not an accident; it’s an important braking mechanism that prevents photosynthesis from producing harmful chemicals, called reactive oxygen species, which can damage or kill the plant.

“It turns out that sunlight can be damaging to plants,” says Dave Kramer, Hannah Distinguished Professor and lead investigator in the Kramer lab.

“When plants cannot use the light energy they are capturing, photosynthesis backs up and toxic chemicals accumulate, potentially destroying parts of the photosynthetic system. It is especially dangerous when light and other conditions, like temperature, change rapidly.”

“We need to figure out how the plant presses on the brakes and tune it so that it responds faster…”

The ATP synthase senses these changes and slows down light capture to prevent damage. In that light, the cfqmutant’s fast ATP is a bad idea for the plant’s well-being.

“It’s as if I promised to make your car run faster by removing the brakes. In fact, it would work, but only for a short while. Then things go very wrong!” Dave says.

“In order to improve photosynthesis, what we need is not to remove the brakes completely, like in cfq, but to control them better,” Dave says. “Specifically, we need to figure out how the plant presses on the brakes and tune it so that it responds faster and more efficiently,” David says.

Atsuko adds: “Scientists are trying different methods to improve photosynthesis. Ultimately, we all want to tackle some long-term problems. Crucially, we need to continue feeding the Earth’s population, which is exploding in size.”

The study is published in the journal, Frontiers in Plant Science.

 

Potatoes, allies on Earth and on Mars

By
Zoraida Portillo (Perú)

[LIMA] A joint initiative between NASA and the International Potato Centre (CIP), which is based in Peru, offers scientific evidence that it is possible to grow at least four types of potatoes on Mars.

A scenario starring the root crop was portrayed in the movie “The Martian” (2015), in which a lost astronaut, played by Matt Damon, survives on potatoes he cultivates on the red planet while awaiting rescue.

But in addition to this interplanetary possibility, scientists also observed the crop is genetically suited to adapting to the changes creating more adverse environmental conditions on Earth.

So before turning fiction into reality, the tuber has a mission on Earth.

papa-en-marte-1-pelicula1.jpg

In the movie “The Martian”, Matt Damon survives eating the potatoes he cultivates on Martian soil. Credit: 20th Century Fox.

The hardy potato quartet
papa-en-marte-2-CIP.jpg

Scientists have studied 65 types of potatoes and have identified four that could grow successfully on Martian soil. Credit: International Potato Center / Mars Project

The study has identified four types of potatoes, out of 65 examined, which have shown resistance to high salinity conditions and were able to form tubers in a type of soil similar to that on Mars.
One of these is the Tacna variety, developed in Peru in 1993. It was introduced to China shortly afterwards, where it showed high tolerance to droughts and saline soils with hardly any need for irrigation.

This variety became so popular in China that it was ‘adopted’ in 2006 under the name of Jizhangshu 8. The same high tolerance was seen on the saline and arid soils of Uzbekistan, a country with high temperatures and water shortages, where the variety was also introduced and renamed as Pskom.

papa-en-marte-3-tacna in china.jpg

In China, the Peruvian Tacna potato variety was renamed Jizhangshu 8. Credit: International Potato Center 

The second variety that passed the salinity test is being cultivated in coastal areas of Bangladesh that have high salinity soils and high temperatures. The other two types are promising clones — potatoes that are being tested for attributes that would make them candidates for becoming new varieties.

These four potato types were created as a result of the CIP’s breeding programme to encourage adaptation to conditions in subtropical lowlands, such as extreme temperatures, which are expected to be strongly affected by climate change.

papa-en-marte-4-bangladesh.jpg

Women harvest resistant potatoes in saline soils in Bangladesh. Credit: International Potato Center

Down to Earth

In addition to these four potato ‘finalists’, other clones and varieties have shown promising results when tested in severe environmental conditions. The findings offer researchers new clues about the genetic traits that can help tubers cope with severe weather scenarios on Earth.

papa-en-marte-5-walter amoros by zp.JPG

Walter Amorós, CIP’s potato breeder is one of the five researchers involved in the project. Credit: Zoraida Portillo

“It was a pleasant surprise to see that the potatoes that we have improved to tolerate adverse conditions were able to produce tubers on this soil [soil similar to that on Mars],” says Walter Amorós, CIP potato breeder and one of the five researchers involved in the project, who has studied potatoes for more than 30 years.

According to Alberto García, adviser to the UN Food and Agriculture Organization in Peru who is in charge of food security programmes, this experiment “serves to verify that potato, a produce of great nutritional value, is a crop extremely adaptable to the worst conditions”, something that is very relevant for current climate scenarios.

García stresses that global temperatures are now rising at a rate higher than expected, affecting not only potatoes but also other crops. Many now need to be cultivated at higher altitudes — which, he says, is not always a disadvantage and may even be beneficial for crops that were previously cultivated in valleys.

papa-en-marte-7-by ZP.jpg

Credit: Zoraida Portillo

“But it can also have negative consequences that we have to anticipate,” adds García. Therefore, he says this experiment can inspire others to think about future scenarios and look for other crops than can adapt to extreme conditions that will have an impact on agriculture.

Similar to Mars

The project began with a search for soils similar to that found on Mars. Julio Valdivia-Silva, a Peruvian researcher who worked at NASA’s Ames Research Center, eventually concluded that the soil samples collected in the Pampas de la Joya region of southern Peru were the most similar to Martian soil.

papa-en-marte-8-julio Valdivia.jpg

Julio Valdivia-Silva took soil samples at Pampa de La Joya, Peru. Credit: NASA/ International Potato Center

Arid, sterile and formed by volcanic rocks, these soil samples were extremely saline.

papa-en-marte-9-roca en la joya.jpg

Credit: Pampas de La Joya Official Site

 

Helped by engineers from the University of Engineering and Technology (UTEC) in Lima and based on designs by NASA’s Ames Research Center, the CIP built CubeSat — a miniature satellite that recreates, in a confined environment, a Martian-like atmosphere. This is where the potatoes were cultivated.

papa-en-marte-10-cubosat.jpg

The varieties were cultivated inside CubeSat, built by the CIP to recreate environmental conditions similar to those on Mars. Credit: International Potato Center / Mars Project

“If potatoes could tolerate the extreme conditions to which we exposed them in our CubeSat, they have a good opportunity to develop on Mars,” says Valdivia-Silva.

They then conducted several rounds of experiments to find out which varieties could better withstand the extreme conditions, and what minimum conditions each crop needed to survive.

papa-en-marte-11-Tierra-Marte-suelos.jpg

La Joya desert, Peru (left); Martian soil (right). Credits: Pampas de La Joya Official Site and NASA, respectively.

CubeSat, hermetically sealed, housed a container with La Joya soil, where each one of the tubers was cultivated. CubeSat itself supplied water and nutrients, controlled the temperature according to that expected at different times on Mars, and also regulated the planet’s pressure, oxygen and carbon dioxide levels.

papa-en-marte-12-compu-CIP.jpg

Connected to a computer, the CubeSat supplied water and nutrients, and imitated other environmental conditions that would be found on Mars. Credit: International Potato Center / Mars Project

 

Cameras were installed to record the process, broadcasting developments on the soil and making it possible to see the precise moment in which potatoes sprouted.

Based on the results, CIP scientists say that in order to grow potatoes on Mars, space missions will have to prepare the soil so it has a loose structure and contains nutrients that allow the tubers to obtain enough oxygen and water.

In a next phase of the project, the scientists hope to expose successful varieties to more extreme environmental conditions. This requires, among other things, developing a prototype satellite similar to CubeSat that can replicate more extreme conditions with greater precision, at a price tag of US$ 100,000.

This piece was produced by SciDev.Net’s Latin America and Caribbean desk.

This article was originally published on SciDev.Net. Read the original article.

The Regulator’s perspective: Why some gene-edited plants are not GM-regulated in Sweden

Staffan Eklof

Dr. Staffan Eklöf, Swedish Board of Agriculture

At July’s New Breeding Technologies workshop held in Gothenburg, Sweden, Dr. Staffan Eklöf, Swedish Board of Agriculture, gave us an insight into their analysis of European Union (EU) regulations, which led to their interpretation that some gene-edited plants are not regulated as genetically modified organisms. We speak to him here on the blog to share the story with you.

 

Could you begin with a brief explanation of your job, and the role of the Competent Authority for GM Plants / Swedish Board of Agriculture?

I am an administrative officer at the Swedish Board of Agriculture (SBA). The SBA is the Swedish Competent authority for most GM plants and ensures that EU regulations and national laws regarding these plants are followed. This includes issuing permits.

 

You reached a key decision on the regulation of some types of CRISPR-Cas9 gene-edited plants. Before we get to that, could you start by explaining what led your team to start working on this issue?

It started when we received questions from two universities about whether they needed to apply for permission to undertake field trials with some plant lines modified using CRISPR/Cas9. The underlying question was whether these plants are included in the gene technology directive or not. According to the Swedish service obligation for authorities, the SBA had to deliver an answer, and thus had to interpret the directive on this point.

 

Arabidopsis thaliana

Image credit: INRA, Jean Weber. Used under license: CC BY 2.0.

 

Could you give a brief overview of Sweden’s analysis of the current EU regulations that led to your interpretation that some CRISPR-Cas9 gene-edited plants are not covered by this legislation?

The following simplification describes our interpretation pretty well; if there is foreign DNA in the plants in question, they are regulated. If not, they are not regulated.

Our interpretation touches on issues such as what is a mutation and what is a hybrid nucleic acid. The first issue is currently under analysis in the European Court of Justice. Other ongoing initiatives in the EU may also change the interpretations we made in the future, as the directive is common for all member states in the EU.

 

CRISPR-Cas9 is a powerful tool that can result in plants with no trace of transgenic material, so it is impossible to tell whether a particular mutation is natural. How did this influence your interpretation?

We based our interpretation on the legal text. The fact that one cannot tell if a plant without foreign DNA is the progeny of a plant that carried foreign DNA or the result of natural mutation strengthened the position that foreign DNA in previous generations should not be an issue. It is the plant in question that should be the matter for analysis.

Arabidopsis thaliana

Image credit: Frost Museum. Used under license: CC BY 2.0.

Does your interpretation apply to all plants generated using CRISPR-Cas9, or a subset of them?

It applies to a subset of these gene-edited plants. CRISPR/Cas9 is a tool that can be used in many different ways. Plants carrying foreign DNA are still regulated, according to our interpretation.

 

What does your interpretation mean for researchers working on CRISPR-Cas9, or farmers who would like to grow gene-edited crops in Sweden?

It is important to note that, with this interpretation, we don’t remove the responsibility of Swedish users to assess whether or not their specific plants are included in the EU directive. We can only tell them how we interpret the directive and what we request from the users in Sweden. Eventually I think there will be EU-wide guidelines on this matter. I should add that our interpretation is also limited to the types of CRISPR-modified plants described in the letters from the two universities.

 

Crops

Will gene-edited crops be grown in Europe in the future? Image credit: Richard Beatson. Used under license: CC BY 2.0.

We are currently waiting for the EU to declare whether CRISPR-Cas9 gene-edited plants will be regulated in Europe. Have policymakers in other European countries been in contact with you regarding Sweden’s decision process?

Yes, there is a clear interest; for example, Finland handled a very similar case. Other European colleagues have also shown an interest.

 

What message would you like plant scientists to take away from this interview? If you could help them to better understand one aspect of policymaking, what would it be?

Our interpretation is just an interpretation and as such, it is limited and can change as a result of what happens; for example, what does not require permission today may do tomorrow. Bear this in mind when planning your research and if you are unsure, it is better to ask. Moreover, even if the SBA (or your country’s equivalent) can’t request any information about the cultivation of plants that are not regulated, it is good to keep us informed.

I think it is vital that legislation meets reality for any subject. It is therefore good that pioneers drive us to deal with difficult questions.

Climate change to push Ethiopian coffee farming uphill

This article was republished from SciDev.Net.

By Baraka Rateng’

Relocating coffee areas, along with forestation and forest conservation, to higher altitudes to cope with climate change could increase Ethiopia‘s coffee farming area fourfold, a study predicts.

The study, published in Nature last month (19 June), suggests that moving Ethiopian coffee fields to higher ground because of climate change could increase resilience by substantially increasing the country’s suitable production area.

Justin Moat, spatial analyst at the UK’s Royal Botanic Gardens Kew, and lead author of the study, says that currently coffee farming is mainly confined to altitudes between 1200 and 2200 metres.

“A critical factor in the suitability of coffee farming is the interaction between rainfall and temperature.”

Justin Moat

“In general, coffee’s niche will move uphill to keep to optimal temperature,“ he tells SciDev.Net. “Much work would be needed to achieve this if planning starts now.”

According to Moat, up to 60 per cent of the country‘s current production area could become unsuitable before the end of the century.

Ethiopia, he says, is the world’s 5th largest coffee producer. The crop provides a quarter of export earnings, and approximately 15 million Ethiopians engage in coffee farming and production.

The study‘s results were based on computer modelling and simulations. “We determined coffee-preferred climate (niche) using a huge amount of data collected on the ground, including historic observations, overlaid on climate maps,” explains Moat.

They projected this niche into the future using climate models and scenarios, which revealed that all the models were in general agreement. They then combined this with satellite imagery to come up with the present-day forest coffee area, and the area projected in the future.

Higher altitudes are forecast to become more suitable for coffee while lower altitudes are projected to become less suitable, according to the study.

“A critical factor in the suitability of coffee farming is the interaction between rainfall and temperature; higher temperatures could be tolerated if there was an increase in rainfall,” Moat notes.

He adds that regardless of interventions, one of the country‘s best known coffee-growing regions — Harar, in eastern Ethiopia — is likely to disappear before the end of the century.

Shem Wandiga, a professor of chemistry at the University of Nairobi’s Institute for Climate Change Adaptation, Kenya, says that although the study cannot predict with full certainty, it holds important messages for policymakers.

“Start planning to expand coffee growing areas to higher elevation, he suggests. “The expansion should be coupled with forestation of the areas.“

Copyright: Panos

Researchers and policymakers should also map out the human, social and ecological conditions that may allow such expansion, according to Wandiga. Also, farmers should slowly substitute coffee with other plants that may bring income.

William Ndegwa, Kitui County director at the Kenya Meteorological Department, says the model used in the research is a powerful tool for linking climate variables with biological parameters.

“This is a very interesting [study] with deep insights into the characteristics of the impacts of climate change on crop production,” he notes.

This piece was produced by SciDev.Net’s Sub-Saharan Africa-English desk.

 

This article was originally published on SciDev.Net. Read the original article.

« Older posts Newer posts »