Phyllody, a related plant growth abnormality affecting flowers.Moniliophthora perniciosa, cause of witch's broom disease in cacao.Melampsora can cause different kinds of witch's brooms.Epicormic shoot – a shoot that develops from buds under the bark.
Plant development § buds and shoots – atypical shoot development.
Witches' brooms provide nesting habitat for birds and mammals, such as the northern flying squirrel, which nests in them. If twigs of witch's brooms are grafted onto normal rootstocks, freak trees result, showing that the attacking organism has changed the inherited growth pattern of the twigs. The broom growths may last for many years, typically for the life of the host plant. The phenomenon can also be caused by other organisms, including fungi, oomycetes, insects, mites, nematodes, phytoplasmas, and viruses. This can be caused by cytokinin, a phytohormone which interferes with growth regulation. In cases of witch's broom, the normal hierarchy of buds is interrupted, and apices grow indiscriminately. The growth of an offshoot is limited by the auxin, while that of the parent branch is not. Causes Ī tree's characteristic shape, or habit, is in part the product of auxins, hormones which control the growth of secondary apices. It is sometimes caused by pathogens.ĭiseases with symptoms of witches' broom, caused by phytoplasmas or basidiomycetes, are economically important in a number of crop plants, including the cocoa tree Theobroma cacao, jujube ( Ziziphus jujuba) and the timber tree Melia azedarach. A dense mass of shoots grows from a single point, with the resulting structure resembling a broom or a bird's nest. Witch's broom or witches' broom is a deformity in a woody plant, typically a tree, where the natural structure of the plant is changed.
Witch's broom in Yamaska National Park, QC Witch's brooms on downy birch, caused by the fungus Taphrina betulina Witch's broom on a white pine. For the nebula, see Witch's Broom Nebula. For a broom associated with witches, see Besom.
0 kommentar(er)
