Journal Article
Witches' broom of lucerne associated with mycoplasma-like organisms in South Africa
Thompson, A. H.,Pietersen, G.
Year1988
JournalPhytophylactica
Volume20
Total pages3
KeywordsAfrica, chlorosis, DISEASE, leaves, lucerne, lucerne, witches' brooms, Electron microscopy, plant pathology, Mollicutes, Tenericutes, bacteria, prokaryotes, viruses, plant pathogens, pathogens, Papilionoideae, Fabaceae, Fabales, dicotyledons, angiosperms, Spermatophyta, plants, Southern Africa, Africa South of Sahara, Africa, Developing Countries, Threshold Coun, MYCOPLASMA-LIKE ORGANISMS, mycoplasma-like organisms, plant viruses, Medicago, phloem, plant, PLANTS
Abstract
Symptoms of plants with the disease from the Transvaal Province included stunting, proliferation of stems, abnormally small leaves, phyllody, negative geotropism and chlorosis. Pleomorphic bodies resembling MLO's were present in the phloem of stems and roots of affected plants only. The bodies were spherical to filamentous and 60-650 nm in diam. Sections of affected roots and stems stained in 4', 6-diamidino-2-phenylindole revealed large numbers of DNA-containing bodies in the phloem, especially around the sieve plates. Attempts to transmit the disease using mechanical methods and dodder (<i>Cuscuta </i>sp.) were unsuccessful. It is concluded that the cause of witches' broom disease on lucerne is probably an MLO