Figure 6.

ptlpd1 alleles confer increased sensitivity to As(III). Five-day-old seedlings (see legend to Fig. 1) of wild-type Col-0, ptlpd1-1, ptlpd1-2, ptlpd1-3, or ptlpd1-4 were transferred to solid medium containing As(III) and grown in a vertical orientation. A, Root length increase was measured after 4 d of growth in the presence of As(III). Means ± se (n = 10–15 seedlings) are shown. B, Shoot-to-root fresh weight (FW) ratios were determined after 10 d of growth on As(III)-containing medium. Means ± se (n = 4 plates; two to four seedlings from a plate were pooled for each replicate) are shown.