Dec 212012
 
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I’ve always enjoyed my job, particularly teaching students and young researchers, but this project has made me think about how I can do more practical science.” – Zeba Seraj, Biochemistry and Molecular Biology Professor, University of Dhaka, Bangladesh

Zeba Seraj

Growing up with a botanist as a father, Zeba Seraj was nurtured to look at plants in a scientific light. But at one stage in her life, she took a different fork on the road: she was more interested in rat livers and cow eyes, before becoming a ‘late bloomer’ in applied science and molecular plant breeding, which is her current niche.

Taking that fork: rats seduced, cows made eyes, but both lost…
Having completed her Undergraduate and Master’s in Biochemistry at the University of Dhaka, Bangladesh, during the 70s and 80s, she moved to Scotland for a PhD at the University of Glasgow. After being persuaded that molecular biology and recombinant DNA technology were not likely to be too different in animals and plants, she focused on the separation of nuclear proteins involved in post-transcriptional processing in the rat liver system.

“I then went on to work as a postdoc at the University of Liverpool, UK, for 18 months, where I worked on a bovine retina cDNA [complementary DNA] library,” Zeba recalls. “I was exposed to a number of recombinant DNA techniques and was pleasantly surprised to find DNA much easier to work with compared to proteins! I enjoyed it, but when I returned to the Bangladesh, there was no work in that field, so I turned to plants.”

The rise of rice, propelled by ‘Petrra’ project and petri dish
Back at her old University, one of Zeba’s first projects was working on salt tolerance in rice which allowed her to set up plant tissue culture facilities and establish a modest molecular biology laboratory. Zeba thereafter worked with the International Rice Research Institute (IRRI) and the Bangladesh Rice Research Institute (BRRI) on the Petrra project (poverty elimination through rice research assistance). The project was funded by the Department for International Development, UK. Meanwhile, she also spent a couple of months in the laboratory of the illustrious Dr John Bennett at IRRI, learning the latest technology in DNA markers and polymerase chain reaction (PCR) technology. This inital work would, in a way, lead her to GCP.

Meeting GCP, and banking on potential
Zeba joined the GCP community in 2005, working on the rice Saltol (salt tolerance) project. She was a focal collaborator in Bangladesh for this IRRI-led project that aimed to revitalise marginal ricelands by discovering and breeding into popular rice varieties ‘survival’ genes to enable rice to not only survive but also thrive on saline or phosphorus-poor soils.

“We were introduced to the project through the Principal Investigator, Abdel Ismail,” recalls Zeba. “Our lab was not very modern, but we did have all the facilities to do marker work, as well as a firm grasp on the theory, so IRRI and GCP must have seen potential in us.”

 …doing the research helped me understand the practical application better… It was a real eye-opener.”

Transiting from theory to practice
After 15 years of working as an associate professor and professor at the University of Dhaka (DU), mainly nurturing young biochemists, Zeba was re-energised by the thought of working on such a practical project that would have a direct impact on her country’s food security, and on its farmers’ livelihoods.

In the background, genotyping in progress at the Department of Biochemistry and Molecular Biology, University of Dhaka. In thef oreground, student– supervisor consultations. Pictured (left to right) are: Zeba I Seraj, Roman, Adnan, Sarwar, Debashis,Rabin, Dost, Mishu, Shamim and Rejbana.

Nearly one million hectares along the Bangladesh coast are affected by varying degrees of salinity which has severely limited the introduction of modern high-yielding rice varieties, as few of these are saline-tolerant. Given Bangladesh’s high population, farmers need as bountiful yields as possible, and minimum risk of failure.

“After reading and teaching theory for so long, it was really exciting to actually put it into practice and work towards a practical outcome,” says Zeba.

“Actually doing the research helped me understand the practical application better too. It was a real eye-opener.”

 Using molecular markers allowed us to at least halve the time it would take to release stress-tolerant rice.” 

Gaining time: the ‘miracles’ and ‘magic’ of molecular makers
Zeba’s lab was responsible for the molecular evaluation and selection of rice lines bred by BRRI for insertion of the genomic region containing Saltol (discovered to confer salt toleranceby the previous IRRI-led GCP-funded project).

Md Sazzadur Rahman of BRRI assesses progress on a salt-tolerant rice variety in the field.

“We collected leaf samples from the BRRI-bred lines which were a combination of popular rice landraces and a Saltol donor.” explains Zeba ‘Landraces’ is ‘breeder-speak’ for varieties grown by, and popular with, farmers, but not necessarily improved by selective scientific breeding. Zeba continues, “We then used molecular markers which would indicate the presence of the Saltol genomic region.”

“The information we gathered guided the breeders at BRRI to select rice plants with the Saltol region. Selected plants were then further analysed with markers, to maximise the presence of popular alleles,” she adds. Allele is one of two, or more, forms of a gene – the alternative form of a gene responsible for a trait producing different effects.

“Using molecular markers allowed us to at least halve the time it would take to release stress-tolerant rice,” Zeba reveals.

 I will be the happiest person on earth the day they release the new lines, knowing that I’d helped to make a difference.”

Seven years on, what next?
Zeba is grateful that she and her lab were active partners in GCP projects for seven consecutive years: first in the IRRI-led project in 2005 to 2009, then in a follow-up supplementary capacity-building DU-led project from 2010 to 2011, for which Zeba was the Principal Investigator.

Nirmal Sharma and Jamal emasculate the first backcross population of a crosscombination for a second backcross at BRRI

“I don’t think we could have done the work without the various GCP networks. Several times in the project we would lag behind and they’d offer us support to get us back on track,” says Zeba. “They also instilled in us the importance of proper data management, and we have now implemented their system to collect, store and report data for all of our projects. We also now have all the equipment and processes in place, meaning that we’re now able to accommodate similar projects, now and into the future.”

Personally Zeba feels the project has given her a new direction in her career that she’s keen to further explore. “I’ve always enjoyed my job, particularly teaching students and young researchers, but this project has made me think about how I can do more practical science,” confides Zeba.

As for the Saltol project, she is keeping a close eye on the application waiting for the news of high-yield salt-tolerant lines becoming accessible to all Bangladeshi rice farmers.

“I will be the happiest person on earth the day they release the new lines, knowing that I’d helped to make a difference.”

Links

  • More on Zeba Seraj on page 40 here
  • The road behind us: read on the early days (2005/2006) of the rice salt-tolerance work:
    • on pages 36–39 here
    • on pages 28–30 here
    • on page 6 here
  • Profile: Abdel Ismail, Principal Investigator of the salt tolerance project

 

Nov 302012
 
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Photo: IRRI

Sigrid Heuer

Meet Sigrid Heuer (pictured), a Molecular Biologist and Senior Scientist at the International Rice Research Institute (IRRI). Her lively and riveting story will take us from Africa through her native Europe and on to Asia, and finally Down Under to Australia.

Origins – the African chapter
Africa holds a special and soft spot in Sigrid’s love affair with science: it was while on this continent that she realised her calling in life as a scientist – linking people doing pure research on plant genes to help plants survive and even thrive in harsh environments, with people who want to apply that knowledge to breed crops that can change the lives of millions of farmers who constantly compromise with nature to make a living.

Photo: IRRI

Fieldwork: Sigrid at a field trial for rice phosphorus uptake.

“Working as a postdoc at the Africa Rice Center in Senegal was a real life-changing experience,” Sigrid recollects with great fondness. “It’s where I found my niche, using my background in theoretical science and applying it to developing crops that could overcome abiotic stresses, and in doing so, make a real impact on people’s lives.”

Rowing further down the river: from upstream to downstream science
Sigrid was born and raised in Hamburg, Germany. She remembers wanting to be a psychologist and didn’t consider science until a few years after finishing school. After completing a biology undergraduate at Phillips University, Marburg, Germany, she returned to her home city of Hamburg to complete a Masters and PhD in plant physiology and molecular biology respectively.

“Back then, I was really involved in upstream science, fascinated in the fine details without much consideration of how such research could benefit society,” says Sigrid. “I still enjoy this form of science and really do value its purpose, but putting it into practice and focusing on the impact that it can have is what really motivates me now.”

Moving to IRRI, and meeting Pup1 and GCP
After three years in Senegal, Sigrid moved to the Philippines to join IRRI in 2003, first as a consultant then as a part-time scientist. In these early years, she was working on several projects, one of which was the GCP-funded Pup1 (rice phosphorus uptake) project.

“The project sought to identify the genes associated with phosphorus uptake in rice lines that could tolerate phosphorus-deficient soils,” says Sigrid. “It was an interesting project in which I was able to use my background in molecular biology. Little by little, I got more and more involved in the Pup1 project and after a year I was asked by Matthias Wissuwa, who was leading the project at the time, if I wanted to take it over. It was a great opportunity which I jumped at, not knowing then how challenging it would prove.”

Pup1 was the first major project I had managed. It was a playground of sorts that allowed me to learn what I needed to know about managing a project – writing proposals and reports, managing budgets and people’s time, and everything else that comes with leading a team.

The ‘root’ and  ‘command post’ where it all happens: Sigrid in the office. For the benefit of our readers, we would have credited the young artist whose colourful work graces the background below the bookshelf, but we were too polite to pry and prise out the young talent’s name, having hogged too much of Sigrid’s time already!

Learning to lead – both work and play

Over the last seven years, Sigrid has been a Principal Investigator and joint leader of the project, which has given her latitude to mature professionally, and not just in science alone. “It’s been tough but personally fulfilling,” Sigrid says, with just a touch of exhaustion.

Pup1 was the first major project I had managed. It was a playground of sorts that allowed me to learn what I needed to know about managing a project – writing proposals and reports, managing budgets and people’s time, and everything else that comes with leading a team. I was really lucky to have Matthias’ help as well as the other experienced collaborators and networks. However, the main factor that made my job a lot less stressful, was the benefit of long-term funding and support from GCP. GCP was always there, supporting us and giving us confidence even when we weren’t sure we were going to succeed.”

Persistence pays: tangible products, plus publication in Nature
In August 2012, Sigrid and her team achieved what they had set out to do seven years ago, through what Sigrid puts down to sheer persistence: their discovery of the Pup1 gene was recognised by their scientific peers and published in the highly renowned journal,  Nature.

Sigrid (3rd left) at the lab with other colleagues in the phosphorus uptake team.

“Having our paper published is really something special and personally my greatest achievement to date,” says Sigrid, but she is also quick to add that it was a team achievement, and that the achievement was in itself humbling.

“It was a double reward for persisting with the research, and with getting it into Nature. We wanted it in Nature for several reasons. To raise awareness on phosphorus deficiency and phosphorus being a limited resource, especially in poorer countries; and to draw attention to how we do molecular breeding these days, which is a speedier, easier and cost-effective approach to developing crops that have the potential to alleviate such problems.”

Sigrid hopes the article will have a lasting impression on readers, and encourage funders to continue to support projects that have such impact on the lives of end-users.

What next? Technology transfer, transitions and torch smoothly passing on…
With the Pup1 gene now found, IRRI researchers are working with breeders from country-based breeding programmes around the world to help them understand the techniques to breed local varieties of rice that can grow in phosphorus-deficient soils. They are also collaborating with other projects that wish to use the Pup1 project as a case study for phosphorous deficiency tolerance in other crops like maize, sorghum, and wheat (see an example here, that includes partners from Africa and Latin America).

Sigrid sees this next stage as a perfect time to step down from the project: she plans to move to Adelaide, Australia at the end of 2012 to lead a new project that is looking at drought and nitrogen deficiency tolerance in wheat.

“Matthias passed the baton on to me, and now I get to pass the baton on to someone else, so it’s nice. And I’ll be sure to always be around to help them too.”

Links

Sigrid’s presentation at the GCP General Research Meeting 2011

 

 

Nov 132012
 
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Bean breeding in his bones: Asrat A Amele

For our bean team, we already see the benefits of being in the Tropical Legumes I  project. We now understand molecular breeding, and we are able to apply molecular breeding techniques.” – Asrat A Amele (pictured)

Asrat is a bean breeder at Ethiopia’s South Agricultural Research Institute (SARI) at the Awassa Research Centre.

Besides breeding beans that will better battle drought, Asrat’s team combines drought tolerance with resistance to the bean stem maggot (BSM) – a pest that afflicts all bean-growing zones in Ethiopia.

Connections, continuity and capacity building
The Tropical Legumes I (TLI) was not an entirely new connection, as Asrat’s involvement with GCP predates this particular project. He started off as a GCP-funded fellow in 2007, investigating bean genetics for drought tolerance. The fellowship would also seem him do a stint in Colombia at the International Center for Tropical Agriculture  (CIAT, by its Spanish acronym). His work at the time on root phenotyping and quantitative trait loci (QTL) analysis has since been published.

At that time, Asrat remarked:

The GCP fellowships programme is great for a person like me, working in a developing-country research institute. I can say it potentially provides researchers with up-to-date scientific knowledge in areas of specialisation. It provides better contact with scientists in other parts of the world and opens a wider window to think on problems and deliver better research products.”

Thorugh GCP, Asrat also attended a molecular breeding course at Wageningen University and Research Centre in The Netherlands. Wageningen is a GCP Consortium member.

The ravages wrought by bean stem maggot.

Having passed through that door of opportunity and looking back now, what does Asrat say? “Through TLI, we were able to access new parental sources of germplasm recommended for release and use for breeding. For instance, we’ve received more than 200 lines from CIAT, from which 10 have been selected to be used as parents. We plan to do crosses with these parents to develop a marker-assisted recurrent selection [MARS] population, based on the problems plaguing beans in Africa.”

And it’s not all about material but also matters cerebral (and matters manual, as we shall see further on): “From the science meetings we attend, we’ve also gained valuable new contacts and acquired new knowledge.” Asrat reveals.

Two…and two

Fitsum Alemayehu

Daniel Ambachew

The next step is to validate the workability of MARS, and SARI has a GCP-funded PhD student, Fistum Alemayehu (pictured right), registered at the South Africa’s Free State University and conducting his phenotyping in Ethiopia, alongside other well-trained staff that SARI now has. Fistum is working on marker-assisted recurrent selection for drought tolerance in beans, while Daniel Ambachew (pictured left), another GCP-funded MSc student enrolled at Haramaya University, Ethiopia, is evaluating recombinant inbred line populations and varieties for combined dual tolerance of drought and bean stem maggot.

Both students are using molecular breeding: “For this work, we’ll be using SNP* markers. It is probably the first use of bean SNPs in sub-Saharan Africa. We will now do QTL analysis with the bean population we have from CIAT,” reveals Asrat.

* SNP: (pronounced ‘snips’) is a technical term, and the abbreviation is derived from ‘single nucleotide polymorphism’ – an advanced molecular-marker system widely used in genetic science. You can read more about SNPs in this press release.

Of humans and machines

A training session on maintaining farm machinery.

Moving on to matters manual and mechanical, besides enhanced human resources, SARI has benefited from infrastructure support as part of GCP’s comprehensive capacity-building package: the Institute now has an irrigation system to enable them conduct drought trials, and SARI technicians from more than 20 different SARI stations have been trained in proper use and routine maintenance of farm machinery. SARI also received two automatic weather stations from GCP for high-precision climatic data capture, with automated data loading and sharing with other partners in the network.

Through this project, SARI is now well tuned into the international arena of bean research and development, and profiting in new ways from this exposure to growing international connections.

Water drilling to install irrigation equipment at SARI.

Institutional revolution and rebirth
The engagement with GCP has revolutionised bean breeding at SARI and institutionalised marker-assisted selection. As a result, SARI will soon have a small molecular breeding laboratory funded by another agency. This lab will support one more PhD student and an additional MSc student, both registered in Ethiopian universities and working on marker-assisted selection for beans.

Thus, in this southern corner of Ethiopia, bean breeders conversant in molecular methods will continue to be ‘born’, better-prepared and well-equipped to meet the challenges facing bean breeding today.

 

 

 

Asrat on video

Links

SLIDES: Phenotyping common beans for tolerance of drought and bean stem maggots in Ethiopia

 

Oct 302012
 
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BREAK-TIME AND BRAKE-TIME from beans for a bit: Steve Beebe takes a pause to strike a pose in a bean field.

“These [molecular breeding] techniques, combined with conventional methods, shorten the time it takes to breed improved varieties  that simultaneoulsy combine several traits.

And this means that we also get them out to farmers more quickly compared to phenotypic selection alone.”
– Steve Beebe

THE NEAR-PERFECT FOOD: Common beans (Phaseolus vulgaris L) comprise the world’s most important food legume, feeding about 200 million people in sub-Saharan Africa alone. Their nutritional value is so high, they have been termed ‘a near-perfect food’. They are also easy to grow, adapting readily to different cropping systems and maturing quickly.

That said, this otherwise versatile, adaptable and dapper dicotyledon does have some inherent drawbacks and ailments that crop science seeks to cure….

Rains are rapidly retreating, and drought doggedly advancing
Despite the crop’s widespread cultivation in Africa, “yields are low, stagnating at between 20 and 30 percent of their potential,” remarks Steve Beebe, GCP’s Product Delivery Coordinator for beans, and a researcher at the International Center for Tropical Agriculture (CIAT, by its Spanish acronym).

“The main problem is drought, brought about by climate change,” he says. “And it’s spreading – it already affects 70 percent of Africa’s major bean-producing regions.”  Drought decimates bean harvests in most of Eastern Africa, but is particularly severe in the mid-altitudes of Ethiopia, Kenya, Tanzania, Malawi and Zimbabwe, as well as in southern Africa as a whole.

A myriad of forms and hues: bean diversity eloquently speaks for itself in this riot of colours.

Drought, doubt and duality − Diversity a double-edged sword
“Common beans can tolerate drought to some extent, using various mechanisms that differ from variety to variety,” explains Steve. But breeding for drought resistance is complicated by the thousands of bean varieties that are available. They differ considerably according to growth habit, seed colour, shape, size and cooking qualities, and cultivation characteristics.

“A variety might be fantastic in resisting drought,” says Steve, ‘but if its plant type demands extra work, the farmers won’t grow it,” he explains. “Likewise, if consumers don’t like the seed colour, or the beans take too long to cook, then they won’t buy.”

Molecular breeding deals a hand, waves a wand, and weaves a band
This is where molecular breeding techniques come in handy, deftly dealing with the complexities of breeding drought-resistant beans that also meet farmer and consumer preferences. No guesswork about it: molecular breeding rapidly and precisely gets to the heart of the matter, and helps weave all these different ‘strands’ together.

The bean research team has developed ‘genetic stocks’, or strains of beans that are crossed with the varieties favoured by farmers and consumers. The ‘crosses’ are made so that the gene or genes with the desired trait are incorporated into the preferred varieties.

The resulting new varieties are then evaluated for their performance in different environments throughout eastern and southern Africa, with particular focus on Ethiopia, Kenya, Malawi and Zimbabwe which are the target countries of the Tropical Legumes I (TLI) project.

Propping up the plant protein: a veritable tapestry of terraces of climbing beans.

GCP supported this foundation work to develop these molecular markers. This type of breeding – known in breeder parlance as marker-assisted selection (MAS) – was also successfully used to combine and aggregate resistance to drought; to pests such as bean stem maggot (BSM); and to diseases such as bean common mosaic necrosis potyvirus (BCNMV) and to bruchid or common bacterial blight (CBB). The resulting ‘combinations’ laden with all this good stuff were then bred into commercial-type bean lines.

“These techniques, combined with conventional methods, shorten the time it takes to breed improved varieties that simultaneoulsy combine several traits,” comments Steve. “This means that we also get them out to farmers more quickly compared to phenotypic selection alone.”

Informed by history and reality
Breeding new useful varieties is greatly aided by first understanding the crop’s genetic diversity, and by always staying connected with the reality on the ground: earlier foundation work facilitated by GCP surfaced the diversity in the bean varieties that farmers grow, and how that diversity could then be broadened with genes to resist drought, pests and disease.

What next?
Over the remaining two years of Phase II of the Tropical Legumes I (TLI) project, the bean team will use the genetic tools and breeding populations to incorporate drought tolerance into farmer- and market-preferred varieties. “Hence, productivity levels on smallholder farms are expected to increase significantly,” says Steve.

Partnerships
The work on beans is led by CIAT, working in partnership with Ethiopia’s South Agricultural Research Institute (SARI),  the Kenya Agricultural Research Institute (KARI),  Malawi’s Department of Agricultural Research and Technical Services (DARTS) and  Zimbabwe’s Crop Breeding Institute (CBI) of the Department of Research and Specialist Services (DR&SS).

Other close collaborators include the eastern, central and southern Africa regional bean research networks (ECABREN and SABRN, their acronyms) which are components of the Pan-African Bean Research Alliance (PABRA). Cornell University (USA) is also involved.

VIDEO: Steve talks about what has been achieved so far in bean research, and what remains to be done

Links

 

Sep 202012
 
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Getting to the core of a world-favourite dessert by unravelling banana’s origin and genealogy

GCP has enabled us to lay a credible foundation, which gave us a leg-up in the intense competition that typifies the genome sequencing arena” – Angélique D’Hont, CIRAD researcher

‘A’ is also for Angélique, as you will see once you read on…

An ‘A’ to our banana team for ushering in a new era in banana genetics. But let soup precede dessert, and don’t let this worry you: stay with us because we’re still very much on the topic and focused on bananas, which offer the whole range from soup and starters, to main course and dessert, plus everything else in between, being central for the food security of more than 400 million people in the tropics: around a third each is produced in Africa, Asia-Pacific and Latin America, and the Caribbean. About 87  percent of all the bananas produced worldwide are grown by small-scale farmers.

Moving back then to soup for starters, we’re serving up our own unique blend of alphanumeric banana ‘soup’, spiced with ABCs, a pinch of 123s, plus a dash of alpha and omega. Curious about the ABCs? Look no further:‘C’ for getting to the core of ‘B’ for bananas, and an ‘A’ score for our ace genomics team that did it.

Read how GCP seeded … and succeeded, in helping open a new era in banana genetics. An achievement by itself, and an important milestone on the road to unlocking genetic diversity for the resource-poor, which is GCP’s raison d’être.

So get your travelling gear please, for time travel with a ‘midspace checkpoint’ in Malaysia.

We start in 2004, when GCP commissioned a survey of diversity with microsatellites (or SSRs, simple sequence repeats) for all mandate food crops in the CGIAR crop research Centres. The objective of that study was to make new genetic diversity from genebank accessions available to breeders.

The endpoint is opening new research avenues to incorporate genes for disease resistance, with the added bonus of an article published in Nature online on July 11 2012, entitled The banana (Musa acuminata) genome and the evolution of monocotyledonous plants.

It may not be quite as easy as the ABC and 123 that The Jacksons promise in song, but we promise you that the science is just as exciting, with practical implications for breeding hardy disease-resistant bananas. Onwards then to the first leg of this three-step journey!

(Prefer a shorter version of this story in pictures? We’ve got it! Choose your medium between Flickr and Facebook)

1) Let’s go Greek: the alpha and omega of it

Rewinding to the beginning

The proof of the pudding is in the eating: we imagine that Jean Christophe Glaszmann just has to be saying “Yummy!” as he samples this banana.

Start point, 2004: “At that time, several research groups had developed SSR markers for bananas, but there was no coordination and only sketchy germplasm studies,” recalls Jean Christophe Glaszmann (pictured), then the leader of what was GCP’s Subprogramme 1 (SP1) on Genetic Diversity on a joint appointment with CIRAD. He stepped down as SP1 Leader in March 2010, and is currently the Director of a multi-institutional research unit Genetic improvement and adaptation of Mediterranean and tropical plants (AGAP, by its French acronym) at France’s Centre de ccoopération internationale en recherche agronomique pour le développement (CIRAD) in Montpellier.

Jean Christophe continues, “The reference studies had been conducted with RFLP* markers, a very useful tool but far too cumbersome for undertaking large surveys. We mobilised Bioversity International, CIRAD and the International Institute of Tropical Agriculture for the project. The process took time, but delivered critical products.[*RFLP stands for restriction fragmented length polymorphism]

Fastforward to 2012, and gets just a little geeky…

Eight years down the road in 2012, the list of achievements is impressive, as evidenced by a suite of published papers which provide the details of the analysis of SSR diversity and describe how the data enabled the researchers to unravel the origin and genealogy of the most important dessert bananas. The origin of the predominant variety – Cavendish – suggested by the markers, involves two rounds of spontaneous hybridisation between three markedly differentiated subspecies. This scheme has been marvellously corroborated by linguistic patterns found in banana variety names as revealed in a paper published in 2011 in the proceedings of USA’s National Academy of Sciences.

But what else happened in between the start- and end-point? We now get to the really ‘sweet’ part of this bonanza for banana breeding!

It is now possible to conduct research to identify and incorporate genes for disease resistance within fertile populations that are close to the early progenitors, and then inter-cross them to re-establish sterility and obtain vigorous, disease-resistant and seedless progenies.

 2) Of bits, bananas, breeding and breadcrumbs

Threading all these bits together for breeding better bananas is akin to following a trail of breadcrumbs, in which GCP played an important facilitating role: where in the germplasm to undertake genetic recombination is one key; and then, how to expedite incorporation of disease resistance and how to control sterility – so as to first suppress it, then re-establish it – is another set of keys that are necessary for proficient breeding.

Hei Leung in the lab at IRRI.

In 2005, Hei Leung (pictured), then Leader of GCP’s Subprogramme 2 on Comparative Genomics (until June 2007) on a dual appointment with the International Rice Research Institute (IRRI), recognised that with GCP’s main focus being drought tolerance in crops, Musa (the banana and plantain botanical genus) was somewhat on the fringe. However, it was still important that GCP support the emergence of banana genomics.

Hei is currently Programme Leader of Genetic Diversity and Gene Discovery at IRRI. He remembers, “We had a highly motivated group of researchers willing to devote their efforts to Musa. Nicolas Roux at Bioversity was a passionate advocate for the partnership. The GCP community could offer a framework for novel interactions among banana-related actors and players working on other crops, such as rice. The team led by Takuji Sasaki of Japan’s National Institute of Agrobiological Science, which had vast experience in rice genome sequencing, added the scientific power. So, living up to its name as a Challenge Programme, GCP decided to take the gamble on banana genomics and help it fly.”

Angélique D’Hont, CIRAD researcher and lead author of the article published in ‘Nature’.

Through several projects, GCP helped consolidate Musa genomic resources, contributed to the establishment of medium-throughput DArT markers as well as the construction of the first saturated genetic map. Additional contributions included the first round of sequencing of large chromosome segments (BAC clones) and its comparison with the rice sequence and a detailed analysis of resistance gene analogues. All these findings have now been published in peer-reviewed journals. And while publication takes time, it still remains a high-premium benchmark for quality and validation of results, and for efficient sharing of information. It reinforces the value of collaboration, builds capacity and gives visibility to all partners, thereby providing potential new avenues for funding.

Such was the case with bananas: using a collaborative partnership framework established with the Global Musa Genomics Consortium, animated by Nicolas Roux and now chaired by Chris Town, the community developed a case for sequencing the genome. With the mentorship of Francis Quétier, contacts were made with various major players in genomics, which in the end formalised a project between France’s CIRAD and CEA–Genoscope, funded by the Agence Nationale de la Recherche and led by Angélique D’Hont (pictured) and Patrick Wincker.

GCP contributed DArT analysis for anchoring the sequence to the genetic map. But, as stressed by Angélique, CIRAD researcher and lead author of the Nature paper: “Above all, GCP has enabled us to lay a credible foundation, which gave us a leg-up in the intense competition that typifies the genome sequencing arena. We were delighted that France rolled the dice in our favour by funding this work.”

3) Musa musings on the road to and from Malaysia checkpoint

Three years down the road, the team published a description of the genome of a wild banana from Malaysia.

Jean Christophe communes with a Musa plant, perhaps musing “What’s your family history and when will you be fully grown?”

Let’s drill down to some technical facts and figures here: the Musa genome has some 520 million nucleotides distributed across 11 chromosomes, revealing traces of past duplications and bearing some 36,000 genes. While most genes derived from duplication tend to lose their function, some develop novel functions that are essential for evolution; bananas seem to have an outstanding range of transcription factors that could be involved in fruit maturity.

And while the road ahead remains long, we now have a good understanding of banana’s genetic diversity, we have genomic templates for functional studies (a whole-gene repertoire) as well as for structural studies (the chromosome arrangement in one subspecies) aimed at unraveling the genomic translocations that could control sterility in the species complex.

It is now possible to conduct research to identify and incorporate genes for disease resistance within fertile populations that are close to the early progenitors, and then inter-cross them to re-establish sterility and obtain vigorous, disease-resistant and seedless progenies.

This is undoubtedly an inspiring challenge towards unlocking the genetic diversity in this crop, which is central to food security for more than 400 million people in the tropics.

Links

 

Sep 072012
 
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Joko infront of his office at ICABIOGRAD’s Molecular Biology Division.

Indonesian upland rice growers can expect to receive improved varieties that thrive in phosphorus-poor soils within a few years, thanks to the hard work of their national breeding programmes.

Joko Prasetiyono is a proud Indonesian researcher who loves rice.

“I don’t know why. I just love researching ways to improve it so it grows and yields better. I also I love to eat it,” says Joko with a laugh.

Having worked as a molecular breeder, concentrating solely on rice for 17 years at the Indonesian Center for Agricultural Biotechnology and Genetic Resources Research and Development (ICABIOGRAD), one would expect a different reaction. But Joko says he’s as interested in the little white grain as much as when he started as an undergraduate with ICABIOGRAD.

And why wouldn’t he be when he and his team are contributing to research that has just been published in Nature and is set to reduce fertiliser application and improve rice yields in Indonesia and the world over by 20 percent!

Improving Indonesian varieties, no genetic modification

Farmers often use phosphate fertilisers to aid in growing rice in these areas, but this option is often too expensive for Indonesian upland growers.

The project has found plants that have a Pup1 locus (a collection of genes), with the specific gene PSTOL1, are able to tolerate phosphorus-deficient conditions and produce better yields than those not suited for the conditions. An Indian rice variety, Kasalath, was one such.

“We are breeding rice varieties that we know have a Pup1 locus and subsequent PSTOL1 gene in them with Indonesian varieties that are suited to Indonesia’s growing systems,” explains Joko.   

Partnering with the International Rice Research Institute (IRRI), ICABIOGRAD and their partner the Indonesian Center for Rice Research (ICRR) have improved the phosphorus tolerance of Indonesian rice varieties Dodokan, Situ Bagendit and Batur.

“The new plants we are creating are not genetically modified; just bred using smarter breeding techniques,” says Joko. “The aim is to breed varieties identical to those that farmers already know and trust, except that they will have the PSTOL1 gene and an improved ability to take up soil phosphorus.”

Joko says that these varieties are currently being tested in field trials and it will take another 2–3 years before Indonesian farmers will have a variety that will yield as well if not better, needing 30–50 percent less fertiliser.

Evolving Indonesian plant research 

ICABIOGRAD team selecting breeding material in 2010. L-R: Masdiar Bustamam, Tintin Suhartini and Ida Hanarida.

GCP is as much about its people and partnerships as its research and products. ICABIOGRAD benefited from a GCP capacity-building grant in mid-2007 to enhance the institute’s capacity in phenotyping and molecular analysis. The grant covered, among other areas, intensive residential staff training at IRRI; PhD student support; infrastructure such as a moist room, temperature-controlled centrifuge apparatus, computers and appropriate specialised software; and  a blast innoculation room. These capacity-building activities were coordinated by Masdiar Bustamam who has since retired, but was then a Senior Scientist at ICABIOGARD.

But coming back to Joko and the PSTOL1 work, Joko started on this project in 2005 as a GCP-funded PhD student at Bogor Agriculture University, Indonesia. He is grateful to be part of a transnational project, which has offered him technical support that he would not otherwise have been able to receive through ICABIOGRAD alone.

IRRI visits ICABIOGRAD in 2009. L-R: Matthias Wissuwa, Sigrid Heuer (both IRRI), Masdiar Bustaman (ICABIOGRAD) and Joong Hyoun Chin

Joko believes the experience of working with IRRI, as a joint partner on this project, will leave an important, and lasting, legacy for researchers at ICABIOGRAD and ICRR. The partnership has also challenged the two local institutes to broaden their horizons past their borders.

“IRRI is teaching us how to use marker-assisted selection and we [ICABIOGRAD and ICRR] are just as busy identifying phosphorus-deficient hotspots in upland areas, choosing the best Indonesian recipient rice varieties for the gene, conducting the breeding and phenotyping testing,” he clarifies.

Breeding for sustainability

The ultimate goal of this project is to help Indonesian growers use marginal land.

Over half the world rice lands are deficient of ‘plant-available’ phosphorus, and Indonesia is no different. Joko explains that while there is plenty of phosphorus in the soil, plants are not able to access it.

“Other minerals in the soil like aluminum, calcium and iron are bound to phosphorus, shielding it from plants roots so they can only absorb a fraction of it.”

Field test of Pup1 lines at Taman Bogo , Indonesia.

In most countries, farmers apply phosphate fertilisers to their crops to combat this deficiency. For Joko this is not a sustainable approach for a lot of Indonesia’s farmers because the fertilisers are expensive and costs will continue to rise as phosphate supplies dwindle.

“Our approach is a lot more sustainable and cost-effective than applying fertiliser. We’ll breed these new plants for phosphorus-poor soils to produce more roots so they can find more phosphorus. The more phosphorus they find, the more of it they can absorb.”

Joko hopes these new plants will help farmers on marginal lands to obtain decent yields without having to spend money on expensive phosphate fertilisers.

“It’s great that our work has been recognised by Nature for publication, but what we really want is to help rice growers here in Indonesia and around the world.”

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Sep 072012
 
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Preparing rice root samples (Photo: IRRI)ALL IN THE ROOTS: A plant’s roots are a marvellously multitalented organ. They act as fingers and mouths helping plants forage and absorb water and nutrients. They act like arms and legs offering a sturdy base of support so a plant doesn’t keel over. They help store food and water, like our stomach and fat cells. And in some plants, can spawn new life – we leave that to your imagination!

That is why it is of little surprise that this multitalented organ was the key to discovering why some rice lines yield better in phosphorus-poor soils, a puzzle whose answer has eluded farmers and researchers… until now.  And even better, the findings hold promise for sorghum, maize and wheat too. Please read on!

 In search of the key – The Gene Trackers
In 1999, Dr Matthias Wissuwa, now with the Japan International Research Centre for Agricultural Sciences (JIRCAS), deduced that Kasalath, a northern Indian rice variety, contained one or more genes that allowed it to grow successfully in low-phosphorus conditions.

For years, Matthias made it his mission to find these genes, only to find it was as easy as finding a needle in a genetic haystack. He teamed up with the International Rice Research Institute (IRRI), and with GCP’s support, the gene trackers were able to narrow the search down to five genes of interest.

“We had started with 68 genes and within three years, we had narrowed in on these five candidate genes. And then, one-by-one, we checked whether they were related to phosphorous uptake,” recollects Dr Sigrid Heuer, senior scientist at IRRI and leader of the team that published the discovery in Nature in August 2012.

Sigrid Heuer at a rice phosphorus uptake demonstration field in The Philippines.

“In the end we found that if a certain protein kinase gene was turned on in tolerant plants like Kasalath, then those plants would perform better in phosphorus-deficient soils.”

They named this protein kinase gene PSTOL1, which stands for Phosphorus Starvation Tolerance. “When we put this gene into intolerant rice varieties that did not have this gene, they performed better in phosphorus-deficient soils.”

The importance of phosphorus
Rice, like all plants, needs phosphorus to survive and thrive. It’s a key element in plant metabolism, root growth, maturity and yield. Plants deficient in phosphorus are often stunted.

Sigrid explains that whereas phosphorus is abundant in most soils, it is however not always easily accessible by plants. “Many soil types bond tightly to phosphorus, surrendering only a tiny amount to plant roots. This is why more than half of the world’s rice lands are phosphorus-deficient.”

Farmers can get around this by applying phosphate fertilisers. However this is a very expensive exercise and is not an option for the majority of the world’s rice growers, especially the poorer ones –the price of rock phosphate has more than doubled since 2007. The practice is also not sustainable since it is a finite resource.

By selecting for rice varieties with PSTOL1, growers will be less reliant on phosphate fertilisers.

How it works: unravelling PSTOL1 mechanics
In phosphorus-poor soils, PSTOL1 switches on during the early stage of root development. The gene tells the plant to grow larger longer roots, which are able to forage through more soil to absorb and store more nutrients.

“By having a larger root surface area, plants can explore a greater area in the soil and find more phosphorus than usual,” says Sigrid. “It’s like having a larger sponge to absorb more water.”

A rice variety — IR-74 — with Pup1 (left) and without Pup1 (right).

Although the researchers focussed on this one key nutrient, they found the extra root growth helped with other vital elements like nitrogen and potassium.

Another by-chance discovery was that phosphorus uptake 1 (Pup1), the collection of genes (locus) where PSTOL1 is found, is present within a large group of rice varieties.

“We found that in upland rice varieties – those bred for drought-prone environments – most have Pup1,” says Sigrid. “So the breeders in these regions have, without knowing it, been selecting for phosphorus tolerance.”

“When thinking about it, it makes sense as phosphorus is very immobile in dry soils, therefore these plants would have had to adapt to grow longer roots to reach water deeper in the soil and this, at the same time, helps to access more reservoirs of phosphorous .”

Breeding for phosphorus tolerance, and going beyond rice
Using conventional breeding methods, Sigrid says that her team introduced PSTOL1 into two irrigated rice varieties and three Indonesian upland varieties, and found that this increased yields by up to 20 percent.

“In our pot experiments,” she added, “when we use soil that is really low in phosphorus, we see yield increases of 60 percent and more. This will mean growers of upland rice varieties will probably benefit the most from these new lines, which is pleasing given they are among the poorest rice growers in the world.”

Read how Indonesian researchers are developing their own breeds of upland rice with the PSTOL1 gene

Sigrid also sheds light on broadening the research to other crop varieties: “The project team is currently looking at Pup1 in sorghum and maize and we are just about to start on wheat.”

Building capacity and ensuring impact
Like all GCP projects, this one invests as much time in building capacity for country breeding programmes as on research.

Sigrid and her team are currently conducting the first Pup1 workshop to train researchers from Bangladesh, India, Indonesia, Nepal, Philippines, Thailand and Vietnam. They will share molecular markers that indicate the presence of PSTOL1, techniques to select for the gene, as well as for new phosphorus-efficient varieties.

Breeding for phosphorus-efficient rice in the Philippines.

“The aim of these workshops is to take these important tools to where they are most needed and allow them to evolve according to the needs and requirements of each country,” says Dr Rajeev Varshney, GCP’s Comparative and Applied Genomics Leader. “Breeders will be able to breed new rice varieties faster and more easily, and with 100 percent certainty that their rice plants will have the gene. Within three to five years, each country will be able to breed varieties identical to those that growers know and trust except that they will now have the Pup1 gene and an improved ability to unlock and take up soil phosphorus.”

Joining hands in collaboration
This IRRI-led project was conducted in collaboration with JIRCAS and the Indonesian Center for Agricultural Biotechnology and Genetic Resources Research and Development (ICABIOGRAD) working with the Indonesian Centre for Rice Research. Other partners included: Italy’s University of Milano, Germany’s Max Planck Institute in Golm, the University of The Philippines at Los Baños, USA’s Cornell University and University of California (Davis and Riverside), Brazil’s EMBRAPA, Africa Rice Center, Iran’s Agricultural Biotechnology Research Institute, Australia’s Commonwealth Scientific and Industrial Research Organisation (CSIRO) and University of Dhaka in Bangladesh.

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Sigrid’s presentation at the GCP General Research Meeting 2011

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