Fig. 1. The halted root (hlr) mutant is defective both in roots and shoots. Phenotypes of wild type (A,B,D,F,H) and hlr-1 (A,C,E,F,G,I). (A) Ten-day-old seedlings of wild-type (WT; left), hlr-1 mutant (center) and the hlr-1 mutant possessing a genomic fragment of the wild-type HLR gene (right). (B,C) Primary roots of 12-day-old wild-type (B) and hlr-1 (C) seedlings. Brackets indicate the area of the root cap. (D,E) Root tips of one-month-old seedlings. White and black arrows indicate the lateral root and the lateral root primordium, respectively. (F,G) Aerial parts of 42-day-old plants. Red arrowhead indicates the secondary inflorescence without cauline leaves, and white arrowheads indicate lateral organs with irregular internode length (higher magnification is shown in G). (H,I) Aerial parts of one-month-old plants. The number on each leaf indicates age order, from young to old leaves. (J) Elongation of primary roots. Each point represents the mean of 100 seedlings. Error bars indicate s.e. (n=103 for wild type; n=100 for hlr-1). Scale bars: 1 cm in A; 500 µm in B,C; 50 µm in D,E.