Disease Note

Witches' Broom of Japanese Persimmon. R. S. Halliwell and M. R. Porterfield, Department of Plant Pathology and Microbiology, Texas A&M University, College Station, TX 77843. Plant Dis. 68:536, 1984. Accepted for publication 17 February 1984. Copyright 1984 The American Phytopathological Society. DOI: 10.1094/PD-68-536f.

Witches' broom symptoms were observed in nonbearing Japanese persimmon (Diospyros kaki L. 'Hachiya').  Healthy young persimmon trees T-budded with buds from naturally infected trees developed witches' broom symptoms within 4–6 wk, whereas controls that received bud from healthy trees remained symptomless.  Infusion of 25 ml of water containing 12.5 mg of tetracycline hydrochloride per tree resulted in resumption of normal growth on symptomatic shoots of naturally and experimentally infected trees; infusion of water only was ineffective.  Electron microscopic examination of ultrathin sections of leaf petioles from symptomatic branches of naturally and experimentally infected persimmon revealed mycoplasmalike organisms (MLO) in phloem cells.  No MLO were observed in cells from symptomless persimmon.