Since plants don't
have the ability to walk around on their own,
diseases need to find a way to get from one plant to
another on their own. Sometimes they have to get
some help and that helper is called a vector.
Due to the fact that
insects are mobile and have the ability to move from
plant to plant, they may become vectors of certain
diseases. In most cases, insect vectors fall into
the category of sucking insects. These critters draw
sap from one plant and them move on to another.
Their mouth parts may be contaminated with bacteria
or virus which is then injected into the next plant.
The most common
insect vectors would include
aphids and
leafhoppers
with
whiteflies,
mealybugs,
grasshoppers,
spider
mites and rarely beetles occasionally acting as
vectors too.