KITAKAMI, Japan and NORWICH, United Kingdom—Scientists are close to developing locally-adapted, salt-tolerant rice by using a new method called MutMap, a method based on whole-genome re-sequencing of pooled DNA from a segregating population of plants that show a useful phenotype, according to a study published in the journal Nature Biotechnology. The findings, particularly important to the Tsunami-ravaged region of Japan, can be used to dramatically accelerate crop breeding.
In MutMap, a mutant is crossed directly to the original wild-type line and then selfed, allowing unequivocal segregation in second filial generation (F2) progeny of subtle phenotypic differences. This approach is particularly amenable to crop species because it minimizes the number of genetic crosses (n = 1 or 0) and mutant F2 progeny that are required.
Researchers at the Iwate Biotechnology Research Center and The Sainsbury Laboratory on Norwich Research Park applied MutMap to seven mutants of a Japanese elite rice cultivar and identified the unique genomic positions most probable to harbor mutations causing pale green leaves and semi-dwarfism, an agronomically relevant trait. The results show that MutMap can accelerate the genetic improvement of rice and other crop plants.
