LISIANTHUS LEAF CURL A NEW DISEASE OF LISIANTHUS CAUSED BY TOMATO YELLOW LEAF CURL VIRUS

In 1992 viruslike symptoms appeared on lisianthus plants grown at different locations in Israel. The symptoms included distortion of the growing tips, cup-shaped leaves, and swelling of veins on the lower surface of the leaves. Plants infected at an early stage did not yield flowers, but late infections did not impair flowering. The viral causal agent of the disease was purified from infected plants and identified with a molecular probe prepared from cloned tomato yellow leaf curl virus (TYLCV) DNA and a specific antiserum against the virus. Purified preparations were infectious to healthy lisianthus in transmission experiments with Bemisia tabaci. These data confirmed that lisianthus leaf curl is caused by TYLCV. This devastating disease has become a limiting factor in the expansion of lisianthus cultivation in Israel.