Figure 5

Chromosomal position and allelic effect of the QTL for root growth angle detected on chromosome 7 in the KD-F2 plants. (a) The peak of the LOD curve indicates the putative position of a QTL for root growth angle. Vertical lines in the linkage map indicate the genetic positions (cM) of the DNA markers. The black bar above the linkage map indicates 1.8-LOD support intervals calculated by using the lodint function in R/qtl. DNA markers are shown under the linkage maps. The horizontal dotted line indicates the LOD threshold (6.20). (b) Frequency distribution for root growth angle in the KD-F2 plants, for three genotypes for the DNA marker (RM5508) closest to the QTL for root growth angle: homozygous for IR64 and Kinandang Patong (KP), or heterozygous. The triangles indicate the position of the mean for each allele, and the horizontal lines indicate the SD. The same shading is used for the triangles and the corresponding bars. The means labeled with different letters differed significantly among the three alleles (P < 0.05, Tukey’s multiple-comparison test).