Figure 4.

The tir1-1 mutant is deficient in IAA-induction of lateral roots. (A) Eight-millimeter root segments were excised from 5-day-old wild-type (open bar) and tir1-1 (solid bar) seedlings grown on nutrient medium and transferred to medium with IAA. Lateral roots were counted after 5 days by use of a dissecting microscope. Bars represent standard errors. Absence of bar indicates error less than thickness of line (n = 10). (B) Ten-day-old wild-type (left) and tir1-1 (right) seedlings grown on 0.5 μm 2,4-D. (Insets) Higher magnification images of roots.