Figure 6.

Ag⁺ Reduces Low K⁺-Induced ROS Production and Low K⁺-Induced Root Hair Elongation in ein2-1.

(A) ROS production increases in ein2-1 under low potassium conditions, and this increase is blocked by Ag⁺. Pseudocolor images (pixel intensity) of ROS fluorescence are shown for K⁺-sufficient (+K, 1.75 mM K⁺) roots and for K⁺-starved (−K, no K⁺) roots with or without Ag⁺ (1, 50 μM; 2-h treatment). Three-day-old ein2-1 roots were used 24 h after K⁺ deprivation. Bar = 200 μm; bar in inset = 100 μm.

(B) Quantified data of images shown in (A) (n = 10 to 15 images of roots ± se).

(C) Root hair length of ein2-1 plants in the absence (−) or presence (+) of 150 nM Ag⁺ under K⁺-sufficient (+K, 5 mM K⁺) and K⁺-deficient (−K, no K⁺) conditions. Root hair length of 3-d-old ein2-1 roots was measured 22 h after K⁺ deprivation and Ag⁺ treatment (n = 10 seedlings, means ± se). Means that have different letters at the top are significantly different (P < 0.05; t test).