The PG samples were collected after dsRNA and PBAN treatments above mention, fixed with 4% formalin (dissolve in phosphate buffered saline), and then stained with Nile Red (Molecular probes, Eugene, OR) as previously described30. Fluorescence microscopy was performed with an Olympus BX-60 system. Nile Red images were captured and processed using Photoshop CS. Relative fluorescence brightness was determined by Quantity One soft (Bio-Rad). Corresponding results were compared using ANOVA and Tukey's test.