Reference "RAPD variation within and between natural populations of the wild rice oryza rufipogon from china and brazil"

Reference ID

1112

Title

RAPD variation within and between natural populations of the wild rice oryza rufipogon from china and brazil

Source

Heredity, 1999, vol. 82, pp. 638-644

Authors (5)

Ge-S	Oliveira-G-C
Schaal-B-A	Gao-L-Z
Hong-D-Y

Abstract

Genetic variation within and between eight natural populations of Oryza
rufipogon from China and Brazil was investigated at the DNA level by analysis of
RAPD fragments. Out of 60 random primers, which were initially screened against
DNA from four individuals, 20 generated highly reproducible RAPD fragments which
were then used for further population analysis. With these primers, 95
discernible DNA fragments were produced and 78 (82.1%) were polymorphic, which
indicated that high levels of genetic variation existed in these natural
populations. In addition, the Chinese populations showed greater polymorphism
than those from Brazil at both the population and regional levels. This is
noteworthy considering that the Chinese populations are from a relatively
restricted area of China. The factors responsible for these findings include the
contrasting mating systems in the Brazilian and Chinese populations, and gene
flow from annual cultivated rice to perennial natural populations in China. An
Analysis of Molecular Variance (AMOVA) was used to apportion the variation
between individuals within populations, between populations within regions, and
between regions. Results showed that 61.8% of the total genetic diversity
resided between the two continents, whereas only 14.9% and 23.3% was
attributable to population differences within regions and to individual
differences within a population, respectively. The great genetic differentiation
between the Chinese and Brazilian populations is in agreement with recent
treatment of the American form of O. rufipogon as a separate species, O.
glumaepatula.