China
Researchers in China have conducted several studies to improve sweet potato through biotechnology. A recent report called “Sweet Potato Omics and Biotechnology in China” published in Plant Omics Journal summarizes China’s advances in sweet potato biotechnology and suggests directions for future research in this area.
China has been using an efficient system of embryogenic suspension cultures for sweet potato genotypes since the 1980s, in which plant regeneration in different tissues via organogenesis or somatic embryogenesis have been successful. Somatic hybridization has also been utilized to overcome incompatibility between sweet potato and its relatives. The first interspecific somatic hybrid was produced by fusing petiole protoplasts of two species.
Cell-induced mutation by gamma ray irradiation and in vitro selection has also been used to produce novel mutants. Employing a method called agrobacterium-mediated transformation, researchers have been able to produce transgenic plants resistant to diseases, stresses and herbicides.
Source: Plant Omics Journal
Bangladesh
Scientists have come up with a potato variety resistant to late blight disease, viruses and drought that wreak havoc on potato production every year in Bangladesh. The National Seed Board under the agriculture ministry has already given clearance to Bari Potato-46, developed jointly by Bangladesh Agricultural Research Institute (Bari) and Peru-based International Potato Centre (CIP).
Bari and CIP will introduce the new seed variety, the first of its kind in Bangladesh, for use next season, arming farmers to fight late blight better. The fungal infection causes farmers to lose 25 to 57 per cent of their yield. The new late blight-resistant potato is also likely to help farmers save money by spending less on fungicides.
Source: The Daily Star
Mexico
A University of Florida scientist has pinpointed Mexico as the origin of the pathogen that caused the Irish Potato Famine in the 1840s, a finding that may help researchers solve the $6 billion-a-year disease that continues to evolve and torment potato and tomato growers around the world.
For more than a century, scientists thought the pathogen that caused late blight originated in Mexico. But a 2007 study contradicted earlier findings, concluding it came from the South American Andes. University of Florida plant pathology assistant professor Erica Goss wanted to clear up the confusion and after analyzing sequenced genes from four strains of the pathogen, found ancestral relationships among them that point to Mexico as the origin.
“The pathogen is very good at overcoming our management strategies,” says Goss. “To come up with better solutions to late blight, we need to understand the genetic changes that allow it to become more aggressive. By understanding past changes, we can design new strategies that are more likely to be robust to future genetic changes.”
Source: University of Florida
United Kingdom
United Kingdom research findings recently published in the journal Philosophical Transactions of the Royal Society showed that genetically modified plants in the study were not infected by late blight. Funded by the Biotechnology and Biological Sciences Research Council (BBSRC) and the Gatsby Foundation, the research indicated that in 2012, the third year of the trial, the potatoes experienced ideal conditions for late blight. None of the plants in the study were inoculated against late blight.
According to researchers, transgenic Desiree plants were 100 per cent infected with late blight by early August of that year while all of the GM plants remained fully resistant right to the end of the experiment. The trial was conducted with Desiree potatoes to address the challenge of building resistance to blight in potato varieties with popular consumer and processing characteristics.
The introduced gene, from a South American wild relative of potato, triggers the plant’s natural defence mechanisms by enabling it to recognize the pathogen. Cultivated potatoes possess around 750 resistance genes but in most varieties, late blight is able to elude them.
“Breeding from wild relatives is laborious and slow and by the time a gene is successfully introduced into a cultivated variety, the late blight pathogen may already have evolved the ability to overcome it,” explains professor Jonathan Jones from the Sainsbury Laboratory at Cambridge University. “With new insights into both the pathogen and its potato host, we can use GM technology to tip the evolutionary balance in favour of potatoes and against late blight.”
In northern Europe, farmers typically spray a potato crop 10 to 15 times, or up to 25 times in a bad year for late blight. R&D efforts are underway to replace chemical control with genetic control, though farmers might be advised to spray even resistant varieties at the end of a season, depending on conditions.
“Potatoes are important agricultural products, and their susceptibility to blight highlights the challenge of producing food in a sustainable way while minimizing effects on the environment,” says Melanie Welham, BBSRC science director. “If we are to explore alternatives to chemicals, we need scientific research on a variety of approaches and technologies that could help us.”
Source: The Biotechnology and Biological Sciences Research Council
