The Yeast Debaryomyces hansenii as a Short-Term Biological Control Agent against Fungal Spoilage of Sawn Pinus sylvestris Timber

Abstract Previous work has found isolates of the yeast genus Debaryomyces to be successful biological control agents against molding of fruits. An isolate of Debaryomyces hansenii was tested for its ability to protect sapwood of Pinus sylvestris timber against visual degrade by surface growth of molds and staining fungi. Successful protection of presterilized wood blocks inoculated with a mixture of common wood molding fungi was achieved when yeast was applied at a rate of 6 × 10 8 CFU/cm 2 . Yeast cells were sprayed onto wood blocks at the same time as spoilage fungi and blocks were incubated under conditions favorable to fungal development for 15 and 25 days before assessment using a visual scale. Protection of presterilized blocks against blue staining by Ophiostomatoid fungi was achieved when yeast cells were applied at a rate of 2 × 10 6 –6 × 10 8 CFU/cm 2 . Significant reduction in disfigurement of nonsterile wood was demonstrated at a yeast application rate of 9 × 10 6 –9 × 10 8 CFU/cm 2 . Survival and reproduction of D. hansenii on sterilized P. sylvestris sapwood blocks were also determined across a range of relative humidities and temperatures previously found to support development of wood molding and staining fungi. Following 4 months incubation at 8–25°C and 93–100% relative humidity, between 46 and 473% of the number of colony-forming units applied to the wood were recovered. Maximum increase in viable yeast count on wood blocks occurred at 100% relative humidity and 15°C.

[1]  H. Staines,et al.  Yeast and Bacteria as Biological Control Agents Against Fungal Discolouration of Pinus sylvestris Blocks in Laboratory-Based Tests and the Role of Antifungal Volatiles , 2000 .

[2]  C. Breuil,et al.  Fungi that cause sapstain in Canadian softwoods , 1999 .

[3]  J. Schnürer,et al.  Pichia anomala as a biocontrol agent during storage of high-moisture feed grain under airtight conditions , 1999 .

[4]  Jeffrey A. Anderson,et al.  Biological Control ofBotrytis cinereain Apple by Yeasts from Various Habitats and Their Putative Mechanisms of Antagonism , 1996 .

[5]  J. Mercier,et al.  Colonization of Apple Wounds by Naturally Occurring Microflora and Introduced Candida oleophila and Their Effect on Infection by Botrytis cinerea during Storage , 1994 .

[6]  R. G. Mcguire.  Application of Candida guilliermondii in commercial citrus coatings for biocontrol of Penicillium digitatum on grapefruits , 1994 .

[7]  A. Hallaksela.  Early interactions of Heterobasidion annosum and Stereum sanguinolentum with non‐decay fungi and bacteria following inoculation into stems of Picea abies , 1993 .

[8]  M. Wingfield,et al.  Ceratocystis and Ophiostoma: Taxonomy, Ecology, and Pathogenicity , 1993 .

[9]  M. Wisniewski,et al.  Mode of action of the postharvest biocontrol yeast, Pichia guilliermondii. I. Characterization of attachment to Botrytis cinerea , 1991 .

[10]  M. Wisniewski,et al.  Characterization of the biocontrol activity of Debaryomyces hansenii in the control of Penicillium digitatum on grapefruit , 1989 .

[11]  N. Magan,et al.  Water relations and metabolism of propionate in two yeasts from hay , 1986 .

[12]  J. P. Blakeman,et al.  Competition for exogenous substrates in vitro by leaf surface micro-organisms and germination of conidia of Botrytis cinerea , 1976 .

[13]  A. Bruce,et al.  The biological control of Serpula lacrymans by Trichoderma species , 1998 .

[14]  A. Bruce,et al.  Biological control of wood decay. , 1998 .

[15]  R. Blanchette,et al.  Biological Control of Blue Stain Fungi on Populus tremuloides Using Selected Ophiostoma Isolates , 1998 .

[16]  A. Bruce,et al.  Forest Products Biotechnology , 1998 .

[17]  R. Blanchette,et al.  Biological control of blue-stain fungi in wood , 1995 .

[18]  T. Highley.  Effect of Scytalidium lignicola on decay resistance and strength of wood , 1994 .

[19]  T. Highley.  COLONIZATION AND CONTROL OF DECAY BY TRICHODERMA IN DOUGLAS-FIR AND SOUTHERN PINE EXPOSED ABOVE GROUND , 1994 .

[20]  K. Seifert.  Sapstain of commercial lumber by species of Ophiostoma and Ceratocystis , 1993 .

[21]  J. Morrell,et al.  Ability of Selected Bacterial and Fungal Bioprotectants to Limit Fungal Stain in Ponderosa Pine Sapwood , 1993 .

[22]  S. Droby,et al.  Biological control of postharvest diseases of grape, peach, and apple with the yeasts Kloeckera apiculata and Candida guilliermondii , 1992 .

[23]  A. Ritschkoff,et al.  Mould growth in pine and spruce sapwood in relation to air humidity and temperature , 1991 .

[24]  J. P. Blakeman.  Microbial ecology of the phylloplane , 1981 .

[25]  J. P. Blakeman,et al.  Competition for nutrients between epiphytic micro-organisms and germination of spores of plant pathogens on beetroot leaves , 1977 .