Lets be clear: one whitefly is a pest. A couple whiteflies are a concern. A whitefly infestation is deadly and should strike fear in your heart. Unfortunately, you rarely see only one whitefly, or a couple whiteflies for that matter. These buggers travel in mass groups, feeding on everything in their path. Remember the plagues brought upon Egypt by God, well think locusts. Thats what dealing with a whitefly infestation is like, absolute carnage. So what kind of threat does a whitefly infestation actually pose?
Whitefly infestations threaten plants and crops in two ways. First and formost, the host of whiteflies feed on those very plants. Due to the sheer size and scale of the the groups in which they travel, entire crops can be destroyed in a short period of time by whitefly infestations. This clear and present danger is ever-present in the minds of farmers, whose livelihoods can be eradicated by a single short-term whitefly infestation. These crop demolitions also result in drastic economic losses, the annual value of which are estimated in the hundreds of millions of dollars. Thats not a small chunk of change.
However, whitefly infestations are not only a threat due to their propensity to directly feed on crops. They also have to capacity to transport plant diseases. In fact, several species of whiteflies are important cogs in the transmission of such diseases- all of which are in the genus Bemisia. Among others, African cassava mosaic, bean golden mosaic, tomato mottle, and bean calico mosaic are all transmitted by this species complex of whiteflies. Furthermore, the presence of such types of whiteflies is steadily increasing. The perpetual metastasis of this problem has triggered the increased usage of pesticides, which are often harmful to the environment. Basically, we have a situation of mutually assured destruction here- with no end in sight.