[6] The S-biotype, reported only from Brazil caused witches' broom symptoms on hosts within the family Solanaceae,[7] including Solanum rugosum; .

Under experimental conditions, this biotype is also able to cause witches' broom symptoms on tomato, aubergine, pepper and potato.

[8] Most recently discovered is the H-biotype, which infects Heteropterys acutifolia (Malpighiaceae) but this has been reclassified as a separate species, Moniliophthora brasiliensis.

[10] Investigation of the breeding biology of these various biotypes found that those causing disease symptoms (C,S) are non-outcrossing (primary homothallic), wherein a single uninucleate basidiospore is capable of completing its life cycle.

Primary homothallism is highly unusual amongst agaric fungi which are outcrossing, requiring mating between mycelia derived from single spore germlings (monokaryons) to form a dikaryon which is capable of basidiome formation.

[6] Infection of M. perniciosa on T. cacao causes Witches’ Broom Disease (WBD), which show distinctive symptoms of hypertrophy and hyperplasia of distal tissue of the infection site, loss of apical dominance, proliferation of auxiliary shoots, and the formation of abnormal stems resulting in a broom-like structure called a green broom.

Parthenocarpy results in M. perniciosa targeting nutrient acquisition while altering the host physiology without causing significant necrosis.

[14] M. perniciosa evolved in the Amazon and its susceptible hosts are tropical plants located in rain forests.

In most cacao production areas, rainfall totals and temperature maximums range between 1300 and 3000 mm and 30 to 33 °C.

This largely affects cocoa production in South American countries where their cash crop is cacao beans.

Due to this disease, Bahia, Brazil went from being the 3rd largest exporter of cacao beans to a net importer.