Figure 6.

Growth Retardation of MGT6 RNAi Seedlings under Mg²⁺-Deficient Conditions.

(A) Growth retardation of the transgenic plants harboring constitutive MGT6 RNAi constructs under Mg²⁺-deficient conditions. Wild-type and MGT6 RNAi seeds were plated on medium containing 0, 0.02, 0.2, or 3 mM Mg²⁺ and photographed after 7 d. Lines 2, 8, and 12, but not line 6, displayed growth retardation under the Mg²⁺-deficient condition. This is consistent with the RNA levels in these lines (Figure 5A). “Vector” represents plants transformed with the empty vector pART27.

(B) Time course of growth retardation of the constitutive MGT6 RNAi lines under Mg²⁺-deficient conditions. Wild-type and RNAi (lines 2, 8, and 12) seeds were plated on Mg²⁺-free MS medium and photographed after growing for 4, 5, or 10 d.

(C) Growth retardation of transgenic plants containing the DEX-inducible MGT6 RNAi construct under Mg²⁺-deficient conditions. Seeds were plated on MS medium containing 0, 0.02, 0.2, or 5 mM Mg²⁺ in the presence (+) or absence (−) of 6 μM DEX. Plants were photographed after 7 d. Lines 30 and 39 showed defects consistent with the RNA levels of MGT6 in these plants (Figure 5B). “Vector” represents plants transformed with the empty vector pTA7002.

Bars = 1.5 cm.