Which of the following is NOT a host for Xylella fastidiosa?

Xylella fastidiosa is a plant pathogenic bacterium that is known to infect a wide range of host plants, leading to various diseases. Understanding the host range of this pathogen is crucial for managing its spread.

Maple trees are not recognized as hosts for Xylella fastidiosa. The bacterium primarily infects plants in certain families such as Arecaceae (palms), Oleaceae (olives), and many others, but not typically maples. This makes the selection of maple trees as the correct answer a valid choice as something that is not a host for this pathogen.

In contrast, rye grass, cocklebur, and blackberry are all documented hosts for Xylella fastidiosa. The presence of these plants in the pathogen's host range can lead to significant management challenges in agricultural and landscape settings, where the vector insects propagate the bacterium from infected hosts to new plants. Thus, knowing which plants are not hosts helps in developing appropriate control measures and disease management strategies for infected crops and landscapes.