Description
Pelargonium Leaf Curl or Crinkle is caused by the Pelargonium leaf-curl virus (PLCV), a strain of tomato bushy stunt virus. It occurs in Europe, the Mediterranean region and in North America. The incidence of the disease ranges up to 45 percent in various greenhouse stocks. The prevalence and severity of infections will differ according to the cultivar involved. Infected cuttings taken in the autumn from apparently healthy plants may exhibit typical symptoms when new leaves develop during the winter and early spring. The severity of the symptoms increases until the middle of spring, when recovery begins. The plants are symptomless during the summer months, and PLCV is difficult to isolate from them at this time. The causal virus is graft-transmitted, and sap-transmissible with some difficulty, not transmitted by seed