Reference "Molecular markers linked to genes underlying seedling tolerance for ferrous iron toxicity"

Reference ID

8054

Title

Molecular markers linked to genes underlying seedling tolerance for ferrous iron toxicity

Source

Plant and Soil, 1997, vol. 196, pp. 317-320

Authors (5)

Wu-P	Luo-A
Zhu-J	Huang-N
Senadhira-D

Abstract

A double haploid (DH) population consisting of 123 lines derived from a japonica
variety, Azucena, and an indica variety, IR64, and 100 BC1F1 (Azucena) lines
were cultivated hydroponically using two treatments: one with excess Fe!2!+ at
the concentration of 250 mg L!-!1 and a control with standard nutrient solution.
Genotypic tolerance was evaluated using an index scale based on degree of leaf
bronzing and relative decease in shoot dry weight (RDSDW) Toxic symptoms were
not observed for Azucena and BC1F1 plants. In contrast, index values for the DH
population indicated segregation for tolerance, and IR64 was moderately
sensitive. Molecular marker loci associated with variations in index values and
in RDSDW, and gene loci for tolerance were detected using 175 Markers mapped on
all 12 chromosomes by single marker loci and interval mapping. Two gene loci
were identified to be flanked by RG345 and RG381, and linked to RG810,
respectively, on chromosome 1 for both index values and RDSDW. They explained
32% and 13% of the total variation in the index values, and 15% and 21% in the
RDSDW in the population, respectively. The variation in RDSDW was also explained
by a locus linked to RG978 on chromosome 8 by about 10%. Comparison of the two
marker genotypic class means indicated that the tolerant alleles were from
Azucena at the first locus on chromosome 1 and the locus on chromosome 8, and
that at the second locus on chromosome 1 from IR64.