Drought tolerance in potatoesJune 30, 2008Hunting for drought tolerance genes in ancient Andean landraces Climate change is expected to exacerbate drought events throughout the world, resulting in large-scale ecosystem alteration and failure of drought-sensitive crops. In addition, periods of drought vary from year to year in severity and length, making it difficult for plants to adapt to more severe conditions. Many modern varieties of potatoes are considered to be drought-sensitive. However, evolution and cultivation in the cold, dry Andean Altiplano gave rise to a number of potato varieties that could tolerate drought. Scientists are studying these varieties to identify the genes and molecular mechanisms of drought tolerance in order to engineer new drought-resistant crops of potato, as well as other Solanaceous vegetables. Dr. Roland Schafleitner and his colleagues, Raymundo Oscar Gutierrez Rosales, Luz Rosalina Tincopa Marca, and Merideth Bonierbale, are examining the genes for drought tolerance traits in several native Andean potato landraces. Dr. Schafleitner, of the Germplasm Enhancement and Crop Improvement Division, International Potato Center in Peru, will be presenting this work at a symposium on the Biology of Solanaceous Species at the annual meeting of the American Society of Plant Biologists in Mérida, Mexico (June 29, 8:30 AM). From tiny dark blue tubers to huge tan bakers, potatoes come in an astonishing variety of colors and sizes, reflecting their genetic variety as well as their long history of cultivation. Potato was first domesticated in the Peruvian Andes over 7,000 years ago and was carried to Europe in the late 16th century, becoming such an important food source that a failure in the crop caused by blight in Ireland triggered a famine. It is a member of the Solanaceae or nightshade family, which also includes tomato, eggplant, tobacco, and chili peppers. Drought first causes stomatal closure, reducing CO2 uptake for photosynthesis, reducing plant growth and yield. Plants vary in the types and speed of responses to drought conditions, depending on their genetic and ecotypic backgrounds, but a number of drought responsive genes are conserved across plant taxa, especially genes involved in osmotic adjustment, detoxification, and cell communication and signaling. Schafleitner and his co-workers studied two Andean potato clones, SA2563 and Sullu (Solanum tuberosum) L. subsp. Andigena (Juz, Bukasov) under field conditions and used microarrays to to identify genes that are up- and down-regulated under drought conditions. The scientists identified about 2000 genes that were differentially regulated under drought conditions. Many of these genes contribute to the increased drought tolerance of the two clones under investigation. Up-regulated genes included transcription factors and cell signaling-related genes such as kinases and phosphatases, which regulate numerous functions, including metabolic changes and cell defense functions. Solute concentrations were increased, lowering osmotic potential, to induce uptake of water from drying soils. Increased expression of lipid transfer genes and fatty-acid and wax synthase genes suggested the reinforcement of cell membranes and cuticles. Genes for cell wall components were also upregulated, as were biosynthetic genes for antioxidants such as flavonoids and anthocyanins, which function in cell protection and detoxification under oxidative stress Many of the ancient potato landraces were adaptations to different environmental conditions such as different soils, temperature, altitude, and drought. Preservation of these varieties and knowledge of their genetic and adaptive histories are of paramount importance as farmers around the world cope with changes in temperature and water availability and struggle to maintain a food supply for growing populations. The International Potato Center in Lima, Peru maintains the world's largest collection of tubers in the interest of conserving the genetic diversity of potato as well as investigating traits such as resistance to various insects and diseases, as well as to cold, heat and drought. The results of this research are used for screening and breeding efforts in crop improvement. The knowledge gained from these efforts can also be applied in crop and yield improvement efforts for other members of the Solanaceae. American Society of Plant Biologists |
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| Related Drought Tolerance Current Events and Drought Tolerance News Articles UCR plant scientist's research spawns new discoveries showing how crops survive drought Breakthrough research done earlier this year by a plant cell biologist at the University of California, Riverside has greatly accelerated scientists' knowledge on how plants and crops can survive difficult environmental conditions such as drought. Hybrid bluegrasses analyzed for use in transition zone The transition zone can be one of the most challenging places to maintain high-quality turfgrass; changeable growing conditions in these regions often prove too hot for some grasses and too cold for others. Finding turfgrass that thrives in these challenging environments can be perplexing for turf management professionals and homeowners alike. Team led by Scripps Research and UC San Diego scientists reveals secrets of drought resistance A team of biologists in California led by researchers at The Scripps Research Institute and the University of California (UC), San Diego has solved the structure of a critical molecule that helps plants survive during droughts. UCR researchers develop genetic map for cowpea, accelerating development of new varieties Cowpea, a protein-rich legume crop, is immensely important in many parts of the world, particularly drought-prone regions of Africa and Asia, where it plays a central role in the diet and economy of hundreds of millions of people. MSU scientist helps map potato genome; move will improve crop yield It's been cultivated for at least 7,000 years and spread from South America to grow on every continent except Antarctica. Now the humble potato has had its genome sequenced. Growing green roofs One way to maximize the eco-friendly factor of a structure is to include a green roof-and this doesn't refer to the paint color. Professor hopes to help high elevation pines grow Thread-like fungi that grow in soils at high elevations may play an important role in restoring whitebark and limber pine forests in Canada. Melon research sweetened with DNA sequence People smell them, thump them and eyeball their shape. But ultimately, it's sweetness and a sense of healthy eating that lands a melon in a shopper's cart. DOE Joint Genome Institute completes soybean genome The U.S. Department of Energy Joint Genome Institute (DOE JGI) has released a complete draft assembly of the soybean (Glycine max) genetic code, making it widely available to the research community to advance new breeding strategies for one of the world's most valuable plant commodities. Smithsonian perspective: Biodiversity in a warmer world Will climate change exceed life's ability to respond? Biodiversity in a Warmer World, published in the Oct. 10, 2008 issue of the journal, Science, illustrates that cross-disciplinary research fostered by the Smithsonian Tropical Research Institute in Panama clearly informs this urgent debate. More Drought Tolerance Current Events and Drought Tolerance News Articles |
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