The Search for Salt-tolerant Rice

The Search for Salt-tolerant Rice
OSU plant geneticist Pankaj Jaiswal explains the process he is pursuing

  1. Climate Adaptability
    More than 3 billion people worldwide depend on rice in their diets. However, rising sea levels and inappropriate use of fertilizers have increased salinity in many areas where rice has traditionally grown.
  2. Taste and Nutrition
    Rice has been bred over millennia to satisfy regional preferences. If a new rice variety is to succeed, it must appeal to regional tastes.
  3. Identify Varieties
    A global search is launched to identify existing rice varieties that match as many of the required traits as possible.
  4. Genetic Mapping
    Promising varieties are genetically mapped in a process called high-throughput sequencing. Pattern-finding algorithms determine which genes are ultimately responsible for the desired traits.
  5. Design PCR
    Using PCR (polymerase chain reaction), sections of DNA are amplified into thousands of samples, making it possible to search quickly for mutations in contrasting varieties that influence each desired trait.
  6. [caption caption="Computational scientist Christopher Sullivan checks the back side of server banks that store the huge volume of data generated by OSU's Center for Genome research and Biocomputing. (Photo by Lynn Ketchum.)"] Genome computers [/caption]

  7. Select Parents
    Two plants with promising genomes­—one carrying the desired salt-tolerant trait—are crossbred to produce the first generation of hybrid rice seed.
  8. Use PCR
    The resulting hybrid seed is cut in half. One half is analyzed by PCR and genetically mapped; the other half is stored for potential planting.
  9. Grow Selections
    The second-generation hybrid seeds with the strongest desirable genomes are selected, planted, and grown to maturity.
  10. Repeat and Refine
    The mature hybrids are selected and crossbred again to refine their mutations. Crossbreeding, selection, and testing are repeated to maximize desirable traits. Additional traits from other promising varieties are introduced into the cycle until the ideal hybrid emerges. The final data are made available for public use.