Figure 7.

NRX1-silenced cotton plants exhibit reduced resistance to V. dahliae infection. A and B, Preliminary assay of the efficiency of VIGS under our experimental conditions. Ten-d-old cotton plants were infiltrated with Agrobacterium carrying VIGS-control vector (TRV:00) and TRV:GbPDS. The photographs were taken at 2 weeks after infiltration. C, D, E, F, G, H, I, and J, Phenotypes of control and VIGS cotton plants. Ten-d-old cotton plants were infiltrated with Agrobacterium carrying VIGS-control vector (TRV:00) or TRV:NRX1 and then at 2 weeks after infiltration inoculated with a suspension of V. dahliae spores. Photographs were taken at 2 weeks after Agrobacterium infiltration (C and D; G and H) and at 2 weeks after V. dahliae infection (E and F; I and J). K, qRT-PCR analysis of NRX1 expression in cotton plants infiltrated with VIGS-control vector (TRV:00) and TRV:NRX1. Error bars indicate sd from three technical replicates of one biological experiment. The experiments were repeated three times with similar results. L and M, Rate of diseased plants and disease index of TRV:00 and TRV:NRX1 cotton plants. Error bars represent sd of three biological replicates (n ≥ 36), asterisks indicate statistically significant differences, as determined by the Student’s t test (**P < 0.01). N, O, P, and Q, qRT-PCR analysis of pathogenesis-related genes (PR1, PR4, PDF1.2, and NPR1) in TRV:00 and TRV:NRX1 cotton plants. Error bars represent sd of three technical replicates of one biological experiment. The experiments were repeated three times with similar results.