Whiteflies

"In tomato production, both open field and greenhouse, management of whiteflies and the viruses they transmit ranks among the highest priorities of growers. Largely driven by the damage of two species, Bemisia tabaci (Gennadius) and Trialeurodes vaporariorum Westwood, a wealth of information has been developed over the last 150 years that informs current whitefly management programs and provides the foundation for such programs in the future. The literature on whiteflies is vast ..."

"Whiteflies, Hemiptera: Aleyrodidae, Bemisia tabaci, a complex of morphologically indistinguishable species ... , are vectors of many plant viruses. Several genera of these whitefly-transmitted plant viruses (Begomovirus, Carlavirus, Crinivirus, Ipomovirus, Torradovirus) include several hundred species of emerging and economically significant pathogens of important food and fiber crops ... These viruses do not replicate in their vector but nevertheless are moved readily from plant to plant by the adult whitefly by various means ... For most of these viruses whitefly feeding is required for acquisition and inoculation, while for others only probing is required. Many of these viruses ... cannot be easily transmitted by other means."

"Virus diseases that have emerged in the past two decades limit the production of important vegetable crops in tropical, subtropical, and temperate regions worldwide, and many of the causal viruses are transmitted by whiteflies (order Hemiptera, family Aleyrodidae). Most of these whitefly-transmitted viruses are begomoviruses (family ), although whiteflies are also vectors of criniviruses, ipomoviruses, torradoviruses, and some carlaviruses. Factors driving the emergence and establishment of whitefly-transmitted diseases include genetic changes in the virus through mutation and recombination, changes in the vector populations coupled with polyphagy of the main vector, , and long distance traffic of plant material or vector insects due to trade of vegetables and ornamental plants. The role of humans in increasing the emergence of virus diseases is obvious, and the effect that climate change may have in the future is unclear."

"Whitefly-borne diseases of plants cause great concern in many tropical areas ... The fact that s, s, s, and other edible , which are primary sources of protein for the diet of many people in the Tropics, fall prey to some of theses agents have prompted local governments and international agencies to institute programs for their study and control ..."

"• Whiteflies are plant phloem feeders and have diverse interactions with host plants. • Plants defend against whitefly attacks by alternations of morphology and physiology. • Whitefly oral secretions, honeydew and endosymbionts regulate plant defense. • Viruses may mediate whitefly–plant interactions directly and indirectly."