Antimicrobial Properties of Nest Volatiles in Red Imported Fire Ants, Solenopsis invicta (Hymenoptera: Formicidae)
Lei Wang, Brad Elliot, Xixuan Jin, Ling Zeng and Jian Chen
Supplementary Materials
Figure S1. The apparatus for testing the inhibitory activity of fire ant nest volatiles on germination and germ tube growth of Beauveria bassiana. A and B are the modified lid and bottle respectively; C is the jar with a hole. On the top of the jar is medium plate in a Petri dish, which is spread with spores of B. bassiana. All connections are sealed with parafilm. D is the jar without a hole
Figure S2. Equipment for testing B. bassiana germination and germ tube growth in modified atmosphere. A: an illustration of the equipment. A flowmeter is used to control the air flow, while two sterilized filters prevent contaminates from entering the jar system. B: the jar lid with two holes (φ=8mm). A pipette tip (1000μl) was inserted into each hole and the connection was fixed with glue. A plastic tube (length is 150mm), was connected to one pipette on the inside of the jar to ensure that gas entering the jar would be distributed initially at the bottom of the container. C: a photo of the equipment during the experiment
Figure S3. Germination of B. bassiana after 18 hours in artificial nest. Control (A), treatment without air change (B), and treatment with air change (C)
Figure S4. Mean (±SE) germination rate (a) and germ tube length (b) of B. bassiana (GHA strain) following exposure to modified or unmodified air (n = 25). Modified air contained 7% CO2 and 12% O2 and unmodified air (control) contained 18.83% O2 and 0.29% CO2
*: Difference between treatment and control is significantly different (p 0.05)
Spore germination rates were significantly higher in modified air than those in the control at 14, 16, and 18h (14 h: t = -6.602, df = 8, p < 0.0001; 16 h: t = -2.705, df = 5.548, p = 0.038; and 18 h: t = -5.406, df = 8, p = 0.001). Germ tube length in the treatment was significantly shorter than that in the control at 14, 16, and 18 h (14 h: t = 5.314, df = 8, p = 0.001; 16 h: t = 3.05, df = 5.194, p = 0.027; and 18 h: t = 7.491, df = 8, p < 0.0001).
Figure S5. Mean (±SE) germination rate (a) and germ tube length (b) of B. bassiana (GHA strain) following exposure to modified or unmodified air (n = 25). Modified air contained 10%CO2 and 8%O2 and unmodified air (control) contained 18.83% O2 and 0.29% CO2
*: Difference between treatment and control is significantly different (p> 0.05)
Germination rates was significantly higher in treatment than those in the control at 14, 16, and 18 h (14 h: t = -2.604, df = 8, p = 0.031; 16 h: t = -3.727, df = 5.12, p = 0.013; and 18 h: t = -15.666, df = 8, p < 0.0001), but significant lower at 10 h (U = 0.000, p = 0.009). Germ tube growth was significantly reduced at 10, 12, and 14 h (10 h: t = 4.206, df = 5.300, p = 0.007; 12 h: t = 2.487, df = 8, p = 0.038; and 14 h: t = 2.783, df = 8, p = 0.024).