Reference "Mapping osmotic adjustment in an advanced back-cross inbred population of rice"

Reference ID

8181

Title

Mapping osmotic adjustment in an advanced back-cross inbred population of rice

Source

Theoretical and applied genetics, 2003, vol. 107, pp. 1288-1296

Authors (9)

Robin-S	Pathan-M-S
Courtois-B	Lafitte-R
Carandang-S	Lanceras-S
Amante-M	Nguyen-H-T
Li-Z

Abstract

Osmotic adjustment is one of several characters putatively associated with
drought tolerance in rice. Indica cultivars are known to have a greater capacity
for osmotic adjustment than japonica cultivars. We developed an advanced back-
cross population using an indica donor, IR62266-42-6-2, to introgress osmotic
adjustment into an elite japonica cultivar, IR60080-46A. One hundred and fifty
BC(3)F(3) families were genotyped using microsatellites and RFLP markers, and a
few candidate genes. We evaluated osmotic adjustment in these lines under
greenhouse conditions using the re-hydration technique. Using the composite
interval mapping technique, we detected 14 QTLs located on chromosomes 1, 2, 3,
4, 5, 7, 8 and 10 that together explained 58% of the phenotypic variability.
Most, but not all, of the alleles with positive effects came from the donor
parent. On chromosome 8, two QTLs were associated in repulsion. The QTL
locations were in good agreement with previous studies on this trait on rice and
in other cereals. Some BC(3)F(3) lines carried the favorable alleles at the two
markers flanking up to four QTLs. Intercrossing these lines followed by marker-
aided selection in their progenies will be necessary to recover lines with
levels of osmotic adjustment equal to the donor parent. The advanced back-cross
strategy appeared to be an appropriate method to accelerate the process of
introgressing interesting traits into elite material.