''Purpureocillium lilacinum'' is a species of filamentous

fungus A fungus ( : fungi or funguses) is any member of the group of eukaryotic organisms that includes microorganisms such as yeasts and molds, as well as the more familiar mushrooms. These organisms are classified as a kingdom, separately from th ...

in the family

Ophiocordycipitaceae Ophiocordycipitaceae is a family of parasitic fungi in the Ascomycota, class Sordariomycetes. Genera *'' Blistum'' *'' Didymobotryopsis'' *'' Haptocillium'' *'' Harposporium'' (Anamorphic) *'' Ophiocordyceps''; anamorphic genera: **''Hirsutella ...

. It has been isolated from a wide range of habitats, including cultivated and uncultivated

soil Soil, also commonly referred to as earth or dirt, is a mixture of organic matter, minerals, gases, liquids, and organisms that together support life. Some scientific definitions distinguish ''dirt'' from ''soil'' by restricting the former te ...

forest A forest is an area of land dominated by trees. Hundreds of definitions of forest are used throughout the world, incorporating factors such as tree density, tree height, land use, legal standing, and ecological function. The United Nations' ...

grassland A grassland is an area where the vegetation is dominated by grasses (Poaceae). However, sedge (Cyperaceae) and rush (Juncaceae) can also be found along with variable proportions of legumes, like clover, and other herbs. Grasslands occur natur ...

desert A desert is a barren area of landscape where little precipitation occurs and, consequently, living conditions are hostile for plant and animal life. The lack of vegetation exposes the unprotected surface of the ground to denudation. About on ...

estuarine An estuary is a partially enclosed coastal body of brackish water with one or more rivers or streams flowing into it, and with a free connection to the open sea. Estuaries form a transition zone between river environments and maritime environment ...

sediments and sewage sludge, and insects. It has also been found in

nematode The nematodes ( or grc-gre, Νηματώδη; la, Nematoda) or roundworms constitute the phylum Nematoda (also called Nemathelminthes), with plant-Parasitism, parasitic nematodes also known as eelworms. They are a diverse animal phylum inhab ...

eggs, and occasionally from females of root-knot and cyst nematodes. In addition, it has frequently been detected in the

rhizosphere The rhizosphere is the narrow region of soil or substrate that is directly influenced by root secretions and associated soil microorganisms known as the root microbiome. Soil pores in the rhizosphere can contain many bacteria and other microor ...

of many crops. The species can grow at a wide range of temperatures – from for a few isolates, with optimal growth in the range . It also has a wide pH tolerance and can grow on a variety of substrates. ''P. lilacinum'' has shown promising results for use as a biocontrol agent to control the growth of destructive

root-knot nematodes Root-knot nematodes are plant-parasitism, parasitic nematodes from the genus ''Meloidogyne''. They exist in soil in areas with hot climates or short winters. About 2000 plants worldwide are susceptible to infection by root-knot nematodes and they ...

Taxonomy and phylogeny

The species was originally described by American mycologist

Charles Thom Charles Thom (November 11, 1872 – May 24, 1956) was an American microbiologist and mycology, mycologist. Born and raised in Illinois, he received his PhD from the University of Missouri, the first such degree awarded by that institution. He w ...

in 1910, under than name ''Penicillium lilacinum''. Taxonomic synonyms include ''Penicillium amethystinum'' Wehmer and ''Spicaria rubidopurpurea'' Aoki. In 1974, Robert A. Samson transferred the species to ''

Paecilomyces ''Paecilomyces'' is a genus of fungi. A number of species in this genus are plant pathogens. Several of the entomopathogenic species, such as "''Paecilomyces fumosoroseus''" have now been placed in the genus '' Isaria'': in the order Hypocreale ...

''. Publications in the 2000s (decade) indicated that the genus ''

'' was not

monophyletic In cladistics for a group of organisms, monophyly is the condition of being a clade—that is, a group of taxa composed only of a common ancestor (or more precisely an ancestral population) and all of its lineal descendants. Monophyletic gro ...

, and that close relatives were ''Paecilomyces nostocoides'', ''Isaria takamizusanensis'' and ''Nomuraea atypicola''. The new genus ''Purpureocillium'' was created to hold the taxon. The generic name refers to the purple conidia produced by the fungus.

Description

''Purpureocillium lilacinum'' forms a dense

mycelium Mycelium (plural mycelia) is a root-like structure of a fungus consisting of a mass of branching, thread-like hyphae. Fungal colonies composed of mycelium are found in and on soil and many other substrate (biology), substrates. A typical single ...

which gives rise to

conidiophores A conidium ( ; ), sometimes termed an asexual chlamydospore or chlamydoconidium (), is an asexual, non-motile spore of a fungus. The word ''conidium'' comes from the Ancient Greek word for dust, ('). They are also called mitospores due to ...

. These bear

phialides The phialide ( ; el, phialis, diminutive of phiale, a broad, flat vessel) is a flask-shaped projection from the vesicle (dilated part of the top of conidiophore) of certain fungi. It projects from the mycelium Mycelium (plural mycelia) is a ...

from the ends of which spores are formed in long chains. Spores germinate when suitable moisture and nutrients are available. Colonies on malt agar grow rather fast, attaining a diameter of 5–7 cm within 14 days at , consisting of a basal felt with a

floccose {{Short pages monitor