Fig. 1.

Difference in Mo concentration between Col-0 and Ler and quantitative trait loci mapping. (A) Comparison of elemental concentrations in shoots of A. thaliana Col-0 and Ler. Col-0 and Ler plants were grown hydroponically in a standard medium (20) for 18 days. The concentration of each element in Ler plants is shown relative to those in Col-0 plants. Averages and standard deviations are shown; n = 5. (B) Quantitative trait loci mapping of Mo concentration. Logarithm of odds (LOD) score curves of chromosomes 1–5 were obtained from the Mo concentration in shoots of the basic set of RI lines derived from a cross between Ler and Col-0 (22). The 18 RI lines and the parental lines were grown hydroponically with the standard medium for 26 days. The curves are derived from the interval-mapping methods by using QGENE software (23). The highest LOD scores on each chromosome are presented. (C) Mapping of MOT1. 16 recombinant inbred lines (Col-0 × Ler) containing recombination between the markers mi238 and er were scored for Mo concentrations and genetic markers. The RI mapping data referred to the data published by the Nottingham Arabidopsis Stock Centre. The RI lines were sorted into two classes based on their shoot Mo concentrations (high, Col-0 type; low, Ler type). The class of each was compared with the genotype in each marker, and the number of mismatches was counted. The arrow and number indicate the position of genetic markers and the count of mismatches. To identify the single locus correlated with the shoot Mo concentration, Col-0 × Ler F₂ lines were analyzed in the same manner. The genotype in each marker in these plants was compared with the class into which they sorted, and the number of mismatches was counted. Thirteen F₂ lines containing recombinations between the markers F3B15_01 and T19L18_01 were found and the count of mismatches in each marker is shown as described above. BAC, bacterial artificial chromosome.