Abstract
It is well known that many plant viruses can be transmitted by aphids, but the highly infectious tobacco mosaic virus (TMV) seems to have no aphid vector. Only Hoggan (1934) reported a very low level of transmission which, however, has not been substantiated (Orlob, 1963; Pirone, 1969). Some progress on this problem was made when Teakle & Sylvester (1962) showed that TMV could be inoculated by aphids placed on virus-covered leaves. More recently we demonstrated that aphids can transmit TMV from a virus-covered leaf to a healthy leaf (Lojek & Orlob, 1969). Now we wish to describe experiments in which the green peach aphid, Myzus persicae Sulz., transmitted TMV from tomato and doubly infected tobacco.
The following plants were used as virus sources: Nicotiana tabacum L. var. Havana or Lycopersicon esculentum L. var. Potentate for TMV or TMV/cucumber mosaic virus (CMV); N. tabacum var. Xanthi n.c. for CMV and potato virus Y (PVY).