Distribution and incidence of atoxigenic Aspergillus flavus VCG in tree crop orchards in California: a strategy for identifying potential antagonists, the example of almonds

To identify predominant isolates for potential use as biocontrol agents, Aspergillus flavus isolates collected from soils of almond, pistachio and fig orchard in the Central Valley of California were tested for their membership to 16 atoxigenic vegetative compatibility groups (VCGs), including YV36,...

Full description

Bibliographic Details
Main Authors: Picot, A., Doster, M., Islam, M., Callicott, K., Ortega Beltran, A., Cotty, P.J., Michailides, T.
Format: Journal Article
Language:Inglés
Published: Elsevier 2018
Subjects:
Online Access:https://hdl.handle.net/10568/96133
_version_ 1855534327755964416
author Picot, A.
Doster, M.
Islam, M.
Callicott, K.
Ortega Beltran, A.
Cotty, P.J.
Michailides, T.
author_browse Callicott, K.
Cotty, P.J.
Doster, M.
Islam, M.
Michailides, T.
Ortega Beltran, A.
Picot, A.
author_facet Picot, A.
Doster, M.
Islam, M.
Callicott, K.
Ortega Beltran, A.
Cotty, P.J.
Michailides, T.
author_sort Picot, A.
collection Repository of Agricultural Research Outputs (CGSpace)
description To identify predominant isolates for potential use as biocontrol agents, Aspergillus flavus isolates collected from soils of almond, pistachio and fig orchard in the Central Valley of California were tested for their membership to 16 atoxigenic vegetative compatibility groups (VCGs), including YV36, the VCG to which AF36, an atoxigenic isolate commercialized in the United States as biopesticide, belongs. A surprisingly large proportion of isolates belonged to YV36 (13.3%, 7.2% and 6.6% of the total almond, pistachio and fig populations, respectively), while the percentage of isolates belonging to the other 15 VCGs ranged from 0% to 2.3%. In order to gain a better insight into the structure and diversity of atoxigenic A. flavus populations and to further identify predominant isolates, seventeen SSR markers were then used to genetically characterize AF36, the 15 type-isolates of the VCGs and 342 atoxigenic isolates of the almond population. There was considerable genetic diversity among isolates with a lack of differentiation among micro-geographical regions or years. Since isolates sharing identical SSR profiles from distinct orchards were rare, we separated them into groups of at least 3 closely-related isolates from distinct orchards that shared identical alleles for at least 15 out of the 17 loci. This led to the identification of 15 groups comprising up to 24 closely-related isolates. The group which contained the largest number of isolates were members of YV36 while five groups were also found to be members of our studied atoxigenic VCGs. These results suggest that these 15 groups, and AF36 in particular, are well adapted to various environmental conditions in California and to tree crops and, as such, are good candidates for use as biocontrol agents.
format Journal Article
id CGSpace96133
institution CGIAR Consortium
language Inglés
publishDate 2018
publishDateRange 2018
publishDateSort 2018
publisher Elsevier
publisherStr Elsevier
record_format dspace
spelling CGSpace961332024-08-29T11:41:34Z Distribution and incidence of atoxigenic Aspergillus flavus VCG in tree crop orchards in California: a strategy for identifying potential antagonists, the example of almonds Picot, A. Doster, M. Islam, M. Callicott, K. Ortega Beltran, A. Cotty, P.J. Michailides, T. aspergillus flavus aflatoxins biocontrol tree crops almonds To identify predominant isolates for potential use as biocontrol agents, Aspergillus flavus isolates collected from soils of almond, pistachio and fig orchard in the Central Valley of California were tested for their membership to 16 atoxigenic vegetative compatibility groups (VCGs), including YV36, the VCG to which AF36, an atoxigenic isolate commercialized in the United States as biopesticide, belongs. A surprisingly large proportion of isolates belonged to YV36 (13.3%, 7.2% and 6.6% of the total almond, pistachio and fig populations, respectively), while the percentage of isolates belonging to the other 15 VCGs ranged from 0% to 2.3%. In order to gain a better insight into the structure and diversity of atoxigenic A. flavus populations and to further identify predominant isolates, seventeen SSR markers were then used to genetically characterize AF36, the 15 type-isolates of the VCGs and 342 atoxigenic isolates of the almond population. There was considerable genetic diversity among isolates with a lack of differentiation among micro-geographical regions or years. Since isolates sharing identical SSR profiles from distinct orchards were rare, we separated them into groups of at least 3 closely-related isolates from distinct orchards that shared identical alleles for at least 15 out of the 17 loci. This led to the identification of 15 groups comprising up to 24 closely-related isolates. The group which contained the largest number of isolates were members of YV36 while five groups were also found to be members of our studied atoxigenic VCGs. These results suggest that these 15 groups, and AF36 in particular, are well adapted to various environmental conditions in California and to tree crops and, as such, are good candidates for use as biocontrol agents. 2018-01 2018-07-13T10:28:19Z 2018-07-13T10:28:19Z Journal Article https://hdl.handle.net/10568/96133 en Limited Access Elsevier Picot, A., Doster, M., Islam, M.S., Callicott, K., Ortega-Beltran, A., Cotty, P. & Michailides, T. (2018). Distribution and incidence of atoxigenic Aspergillus flavus VCG in tree crop orchards in California: A strategy for identifying potential antagonists, the example of almonds. International Journal of Food Microbiology, 265, 55-64.
spellingShingle aspergillus flavus
aflatoxins
biocontrol
tree crops
almonds
Picot, A.
Doster, M.
Islam, M.
Callicott, K.
Ortega Beltran, A.
Cotty, P.J.
Michailides, T.
Distribution and incidence of atoxigenic Aspergillus flavus VCG in tree crop orchards in California: a strategy for identifying potential antagonists, the example of almonds
title Distribution and incidence of atoxigenic Aspergillus flavus VCG in tree crop orchards in California: a strategy for identifying potential antagonists, the example of almonds
title_full Distribution and incidence of atoxigenic Aspergillus flavus VCG in tree crop orchards in California: a strategy for identifying potential antagonists, the example of almonds
title_fullStr Distribution and incidence of atoxigenic Aspergillus flavus VCG in tree crop orchards in California: a strategy for identifying potential antagonists, the example of almonds
title_full_unstemmed Distribution and incidence of atoxigenic Aspergillus flavus VCG in tree crop orchards in California: a strategy for identifying potential antagonists, the example of almonds
title_short Distribution and incidence of atoxigenic Aspergillus flavus VCG in tree crop orchards in California: a strategy for identifying potential antagonists, the example of almonds
title_sort distribution and incidence of atoxigenic aspergillus flavus vcg in tree crop orchards in california a strategy for identifying potential antagonists the example of almonds
topic aspergillus flavus
aflatoxins
biocontrol
tree crops
almonds
url https://hdl.handle.net/10568/96133
work_keys_str_mv AT picota distributionandincidenceofatoxigenicaspergillusflavusvcgintreecroporchardsincaliforniaastrategyforidentifyingpotentialantagoniststheexampleofalmonds
AT dosterm distributionandincidenceofatoxigenicaspergillusflavusvcgintreecroporchardsincaliforniaastrategyforidentifyingpotentialantagoniststheexampleofalmonds
AT islamm distributionandincidenceofatoxigenicaspergillusflavusvcgintreecroporchardsincaliforniaastrategyforidentifyingpotentialantagoniststheexampleofalmonds
AT callicottk distributionandincidenceofatoxigenicaspergillusflavusvcgintreecroporchardsincaliforniaastrategyforidentifyingpotentialantagoniststheexampleofalmonds
AT ortegabeltrana distributionandincidenceofatoxigenicaspergillusflavusvcgintreecroporchardsincaliforniaastrategyforidentifyingpotentialantagoniststheexampleofalmonds
AT cottypj distributionandincidenceofatoxigenicaspergillusflavusvcgintreecroporchardsincaliforniaastrategyforidentifyingpotentialantagoniststheexampleofalmonds
AT michailidest distributionandincidenceofatoxigenicaspergillusflavusvcgintreecroporchardsincaliforniaastrategyforidentifyingpotentialantagoniststheexampleofalmonds