An Important Virus Disease of Lilium longiflorum and its Varieties

Abstract

IN the course of work on the diseases of lilies I have shown by means of controlled experiments that an important disease occurring on Lilium longiflorum Thunberg and its well-known varieties of commerce, Lilium giganteum (L. longiflorum var. takesima Duchartre), Lilium formosum (L. Iongiflorum var. insulate Hort. apud Mallett), and Lilium Harrisii (L. longiflorum var. eximium Baker), belongs to the group of filterable virus diseases and is transmitted by the aphid Aphis lilii Takahashi (very close to A. gosaypii Glov.). The identification of the insect was made by Dr. F. V. Theobald.