Article Figures & Data
Figures
- Fig. 1.
BA effect on length of hypocotyls (a) and roots (b) of 5-d-old etiolated seedlings. Wild-type (▪) anddgt (□) seeds were germinated for 2 d and then grown on BA media for 3 d. Error bars represent the ses from three independent experiments.
- Fig. 2.
BA-induced ethylene biosynthesis by etiolated wild-type (▪) and dgt (□) seedlings. Error bars represent the ses from three independent experiments (*,n = 3; **, n = 8; all others,n = 11).
- Fig. 3.
Inhibition of shoot fresh weight accumulation by BA in 7-week-old light-grown wild-type (black bars) anddgt (white bars) plants. Error bars represent the ses from all harvested plants (n >12). Inset contains the same data expressed as percentage inhibition relative to untreated controls for both wild type (squares) anddgt (circles). Similar effects were observed in three independent experiments.
- Fig. 4.
Reduction of internode length by BA in 7-week-old light-grown wild-type (a) and dgt (b) plants watered with 30 (○), 10 (•), 3 (□), and 0 (▪) μm BA. Error bars represent ses (n >12). Effects were similar in three independent experiments.
- Fig. 5.
Low levels of auxin or cytokinin differentially modulate organ regeneration in wild-type and dgthypocotyl explants. Hypocotyl segments from 9-d-old light-grown seedlings were incubated on Murashige-Skoog media in the light for 4 weeks. a, Regeneration of shoots and roots from untreated wild-type and mutant hypocotyl segments; b, organ formation in the presence of 0.3 μm 2,4-D; and c, inhibition of organ formation by 0.3 μm BA.
- Fig. 6.
Auxin (2,4-D) and cytokinin (BA) effects on callus production and root formation by wild-type and dgthypocotyl segments. Hypocotyl segments from 9-d-old, light-grown seedlings were incubated for 1 month in the light on Murashige-Skoog media containing the indicated concentrations of 2,4-D and BA. For each treatment, a representative wild-type explant is shown to the left of the corresponding dgt explant.
- Fig. 7.
Callus and root formation in wild-type anddgt hypocotyl explants from 9-d-old light-grown seedlings incubated for 1 month in the dark on Murashige-Skoog media containing the indicated hormones.
- Fig. 8.
Responses of callus induction and growth to 2,4-D and BA. a, Callus induction from hypocotyl tissue; b, growth of callus subcultured in the dark for 2 additional months. The average fresh weight of four callus pieces is represented by the area of each circle. The experimental setup was the same as for Figure 7.
- Fig. 9.
Models depicting possible auxin-cytokinin interactions in specific tissues or responses. a, Auxin-cytokinin cross-resistance of dgt tissues could indicate either cytokinin-induced changes in active auxin pools or interactions between cytokinin- and auxin-signaling pathways; b, lack of auxin-cytokinin cross-resistance suggests separate mechanisms of auxin and cytokinin action. ▾ indicates inhibition and ▴ indicates stimulation of the processes or responses specified.
