Figure 1.

Effect of Mt-CASTOR-RNAi on Nodulation and Arbuscular Mycorrhization in M. truncatula.

(A) Reduction in the expression of Mt-CASTOR did not result in a reduction in the nodulation rate when compared with the control empty vector–expressing transgenic roots, whereas reduction in the expression level of DMI1 (used here as a positive control) resulted in a significant reduction in the nodulation rate when compared with the control empty vector expressing transgenic roots. Data are mean ± sd (n + 90).

(B) Mt-CASTOR-RNAi–expressing transgenic root displaying mycorrhizal association with G. intraradices, as is evident from the presence of arbuscules (n + 36). Asterisks indicate arbuscules in the root epidermal cells. Bar + 20 μm.

(C) Analysis of Mt-PT4 expression level in four AM-colonized Mt-CASTOR-RNAi–expressing roots (lanes 1 to 4) and control root (lane 5) by RT-PCR. Each lane represents three technical replicates obtained from one experiment comprising 12 plants each for Mt-CASTOR-RNAi and empty vector control. The experiment was repeated three times; n + 36. Mt-Actin was used as a loading control.

[See online article for color version of this figure.]