Floral phenotypes of ub2 and ub3 mutants. (A) Tassel phenotypes of ub2 and ub3 mutant alleles; ub2-mum1, ub3-mum1, and the double mutant are in the W22 inbred background. Triple-mutant tassel in the W22 background is shown in Inset. (B) Ear phenotypes of W22 and double mutants. (C) Razor blade hand sections of the midpoint of the ears in C. Asterisks indicate kernel rows. (D) Fertilized ears of the double mutant compared with WT A619. (E) Mature field-grown plants of W22, ub2, ub3, and the double mutant. (F) Mature field-grown plants of tsh4 and double- and triple-mutant combinations in W22 background showing an increase in tillering.