Pythium ultimum Trow 1901
Details
Pythium ultimum Trow, Ann. Bot. (London) 15 300 (1901)
Nomenclature
Trow
Trow
1901
300
ICN
Pythium ultimum Trow 1901
species
Pythium ultimum
Classification
Associations
has host
Descriptions
Pythium ultimum Trow 1901
It commonly occurs throughout New Zealand associated wide damping-off of seedlings in nursery rows and in newly sown crops. It may be controlled by seed dusting prior to sowing. Soil drenching with an organic fungicide such as captan may be used if damping-off due to Pythium develops in seed pans in nurseries. Copper fungicides may be used-but with caution, as with some seedlings it gives serious root burn. Brien (1940b) associated it with a storage rot of potatoes known as "leak", where it may be of considerable economic importance.
Pythium ultimum Trow 1901
Type: Radicicolous Fungi; Description: Colonies on corn meal agar with cottony white aerial mycelium, main hyphae up to 11 μm wide. Sporangia terminal or intercalary, globose to subglobose, 10–30 μm in diameter. Oogonia terminal, globose, 19–27 μm in diameter, smooth. Antheridia 1–2 per oogonium, sessile, arising close to the apex of the oogonial stalk. Oospores aplerotic, 14–22 μm in diameter.
Distribution: Northland, Auckland, Bay of Plenty, Rangitikei, Wanganui, Wellington, Gisborne, Hawkes Bay, Wairarapa, Marlborough, Mid Canterbury, South Canterbury, Dunedin.; 1st Record: Brien & Dingley (1953).
Significance: A common and widespread cause of damping-off and root rot in seedlings. Reported to be highly pathogenic to roots of vegetable seedlings (Robertson 1976). In a survey of forest nursery diseases it was the most commonly found pathogen, causing periodic severe root rot in Larix decidua, Pinus nigra subsp. laricio, P. radiata, and Pseudotsuga menziesii (Bassett 1961).; Host(s): Acacia leprosa, Agathis australis, Araucaria heterophylla, Chamaecyparis lawsoniana, Citrus sp., Correa ×harrisii, Cupressus lusitanica, Dodonaea viscosa, Goodia lotifolia, Humulus lupulus, Larix decidua, Malus ×domestica, Persea americana, Picea sitchensis, Pinus nigra subsp. laricio, P. radiata, Pseudotsuga menziesii, Vitis vinifera.
Taxonomic concepts
Pythium ultimum Trow 1901
Pythium ultimum Trow 1901
Pythium ultimum Trow 1901
Pythium ultimum Trow (1901)
Pythium ultimum Trow 1901
Pythium ultimum Trow (1901)
Pythium ultimum Trow 1901
Pythium ultimum Trow (1901)
Pythium ultimum Trow 1901
Pythium ultimum Trow (1901)
Global name resources
Collections
Metadata
1cb1a115-36b9-11d5-9548-00d0592d548c
scientific name
Names_Fungi
17 November 2013