Abstract
Cotton leaf crumple (CLC) occurred in Arizona [USA] cotton-growing areas during 1981-1985. The disease is incited by the CLC virus (CLCV), a whitefly-transmitted virus with geminate particle morphology. Results of an extensive host range study indicated CLCV infects numerous plant species within the Malvaceae and Lerguminosae and thus has a wider host range than previously recognized. Hosts include both weed and cultivated plants found in the southwestern United States and northern Mexico; therefore, previously unidentified, year-round virus and/or vector reservoirs probably exist in these cotton-growing regions. Transmission studies carried out in a growth chamber at 26, 32, and 37 C indicated optimal efficiency of transmission was at 32 C and that whiteflies transmitted CLCV with 100% efficiency when more than 10 insects per plant were used. Based on virus-vector relationships (acquisition and inoculation access times, latent period, and persistence in the vector), using groups of insects in each case, the CLCV isolate from Arizona is similar to the CLCV isolate originally described from California in 1954.