ASSOCIATION OF PHYTOPLASMAS WITH A WITCHES-BROOM DISEASE OF WITHANIA-SOMNIFERA (L) DUNAL IN INDIA

A witches-broom disease of Withania somnifera first appeared in 1988 a t CIMAP experimental fields, Lucknow, India. Thereafter, it spread to the commercial fields causing severe damage to the crop during the las t 5 years. Phytoplasma was associated with the disease on the basis of symptomatology, mode of transmission, electronmicroscopic studies and response of tetracycline spray on the recovery from diseased symptoms . Typical symptoms of the disease consisted of little leaf shortening of internodes, excessive branching giving witches-broom appearance and premature drying and death of infected twigs and leaves. Ultrathin se ctions of infected leaf tissue showed pleomorphic bodies (measuring 25 0-550 nm) in sieve tubes of phloem. Disease was transmitted from infec ted plants to healthy plants through grafting. The treatment of infect ed plants with tetracycline provided temporary recovery from the infec tion.