Weed hosts of Bemisia tabaci biotype B in Italy
In Central Italy, laboratory studies were carried out on the host preference and performance of Bemisia tabaci biotype B (also referred to as B. argentifolii - EPPO A2 quarantine pest) on weeds found around cultivated greenhouses. 18 weed species were proposed to whiteflies in a choice test, and several parameters of the insect life cycle were measured to assess the effects of the different host plants on the developmental rate. Out of the 18 weed species, 10 were accepted by B. tabaci biotype B populations. After 72 h, whiteflies showed a marked preference for Sonchus oleraceus and Solanum nigrum (53 % of the total insect population). A large part of the remaining population preferred: Conyza canadensis, Euphorbia helioscopia, E. peplus, Trifolium repens, and a very low number of insects were found on Ricinus communis, Euphorbia characias, E. maculata and E. dendroides. The life table statistics coincided with the ranking of host preference. The authors noted that even in the absence of cultivated host plants such as tomato, courgette etc., B. tabaci biotype B can find weed hosts on which it can complete its development. However, they stressed that these laboratory studies still need to be confirmed in field experiments.
Note: the EPPO Secretariat had previously no data on the occurrence of B. tabaci biotype B in Italy.
Calvitti, M.; Remotti, P.C. (1998) Host preference and performance of Bemisia argentifolii (Homoptera: Aleyrodidae) on weeds in Central Italy.
Environmental Entomology, 27(6), 1350-1356.