Two whitefly ( whiteflies ) rather polyphagous are damaging in France zucchini: Trialeurodes vaporariorum (Westwood) and Bemisia tabaci (Gennadius). This last species is represented (in certain populations) by a particularly formidable biotype-B, also known under the name of B. argentifolii (Bellows & Perring), which develops on more than 900 hosts. These whiteflies belong to the order Hemiptera and the family Aleyrodidae. T. vaporariorum , also called “ white greenhouse fly ”, originates from Central America and has been rampant for many years in Europe, particularly under shelters. B. tabaci , the tobacco whitefly , described for the first time in Greece, has been emerging for several decades in several regions of the world (since 1988 in France). It has become problematic everywhere for at least three reasons:

• its high population levels are responsible for significant damage;

• the resistance of some of its populations to one or more insecticides calls into question the effectiveness of chemical control.