Figure 7

Knocking down wheat autophagy-related ATG6 genes enhances the basal resistance of susceptible plants to Blumeria graminis f. sp. tritici ( Bgt ). Barley stripe mosaic virus (BSMV)-treated Yangmai 158 plants of the six-leaf stage were heavily inoculated with Bgt conidia. (A) Representative images of mildew colonies on the fourth leaves of BSMV-treated Yangmai 158 plants. Images were taken at 5 days after inoculation (dai) with Bgt conidia. (B) Sporulation of Bgt colonies on BSMV-treated Yangmai 158 plants. Leaf discs with visible mildew colonies were gently harvested from different regions of the fourth leaves at 5 dai, immersed in 0.01% glycerol and subjected to ultrasonic treatment for 1 min to disperse the conidia. The conidial production per mildew colony was counted by microscopic observation. Values represent the mean conidial production per mildew colony ± SD of at least 50 mildew colonies from five plants. Asterisks indicate a significant difference (P < 0.05, Student’s t test) between the BSMV:ATG6-treated plants and BSMV:GFP-treated control plants of Yangmai 158. (C) Percentage of mycelia with mature chains of conidia on BSMV-treated Yangmai 158 plants. Fungal structures were stained by trypan blue and visualized by light microscopy. The number of mycelium with mature chains of conidia on the fourth leaves was counted at 5 dai. At least 100 mycelia from five individual plants were counted and values represent the mean percentage of mycelia with mature conidia ± SEM.