The scientists then used a different setup, hiding the targets in chambers connected to dodder sprouts only by curving pipes, so the vine could find them only by smell.
By placing dodder sprouts near different plants, the scientists found that the type of dodder that they were studying prefers tomatoes and a flower called impatiens.
One of these ingredients turns up in wheat perfume, but the wheat perfume also contains a substance that repels dodder sprouts.
29 Science, the team took a different point of view, looking at how an attacker, the dodder, takes advantage of volatiles to target its prey.
At first, the researchers set various possible targets several centimeters from dodder sprouts.
Testing various victim species, the researchers found that dodder grows toward impatiens and tomatoes.
When researchers tested seven ingredients in the tomato perfume individually, three of them proved attractive to the dodder.
Following dodder attachment to pairs of donor and receiver host plants, I randomly assigned plant pairs to one of four treatments: 1) donor plant shaded, 2) donor plant fertilized, 3) donor plant shaded and fertilized, or 4) control.
Due to the rapid growth rate of the dodder parasite, it was difficult to control the number of stems connecting donor and receiver plants.
I used regression analysis to test whether the number of dodder stems connecting plant pairs was significantly correlated to the growth of either plant.