A possible role for Rhizoglyphus robustus Nesbitt (Astigmata: Acaridae) in transmission of Sclerotium cepivorum Berk. (Deuteromycetes: Mycelia-Sterilia).

Abstract

We evaluated the viability of Sclerotium cepivorum Berk. (causal agent of of garlic and onion white rot) mycelial and sclerotial fragments transported through excreta of Rhizoglyphus robustus Nesbitt fed on S. cepivorum. Excreta were obtained from mites fed on 1) mature, hydrated and fragmented sclerotia (mhfS); 2) mature, dehydrated and fragmented sclerotia (mdhfS); 3) whole mature sclerotia (wmS); 4) mycelium (M) and 5) potato dextrose agar culture media (PDA). After feeding, mite excreta were examined under compound and scanning electron microscopes for the presence of mycelial and sclerotial fragments. S. cepivorum mycelium growth and sclerotia formation were observed in three out of 60 excreta pellets from mites fed on M and mhfS and only in one excreta pellet out of 60 from mites fed on mature, dehydrated and fragmented sclerotia (mdhfS). Numerous fragments of mycelia and sclerotia on the mites' bodies, mainly on the sense organs of the ambulacral appendages and the mouthparts were identified by compound and scanning electron microscope observations. R. robustus may also influence white rot epidemiology as a consumer of S. cepivorum and spread and/or transmit the pathogen by carrying fungal fragments on its body externally.

Tyrophagus putrescentiae as Causative Agent of Wet Bubble Disease in Agaricus bisporus

“…In all cases, only females were responsible for fungal transfer. Although there is no data concerning the viability of the spores transported in the sporotheca, mites might act as fungi spreaders transporting spores inside or outside their bodies to other possible substrates, rewarded at the same time by being provided with mycelia for a new colony of mites (Ramírez-Suárez et al, 2002). Eggs were laid among the faecal pellets, indicating that fungi play an important role in the mites' cycle of development (Ebermann and Hall, 2003).…”

Growth, fruiting body development and laccase production of selected coprini

“…Although there is no data concerning the viability of the spores transported in the sporotheca, mites might act as fungi spreaders transporting spores inside or outside their bodies to other possible substrates, rewarded at the same time by being provided with mycelia for a new colony of mites (Janke and Lubkowitz 1953, Okabe 1999, Ramírez-Suárez et al 2002. In this study we observed a minor possible route of fungal spore distribution by attachment of fungal spores to the mite body (Figure 5), and a major route through the mite's faeces.…”