Resistance to aspergillus flavus and aspergillus parasiticus in almond advanced selections and cultivars and its interaction with the aflatoxin biocontrol strategy

Aflatoxin contamination of almond kernels, caused by Aspergillus flavus and A. parasiticus, is a severe concern for growers because of its high toxicity. In California, the global leader of almond production, aflatoxin can be managed by applying the biological control strain AF36 of A. flavus and se...

Descripción completa

Detalles Bibliográficos
Autores principales: Moral, J., Garcia-Lopez, M.T., Gordon, A., Ortega Beltran, A., Puckett, R.D., Tomari, R., Gradziel, T.M., Michailides, T.
Formato: Journal Article
Lenguaje:Inglés
Publicado: Scientific Societies 2022
Materias:
Acceso en línea:https://hdl.handle.net/10568/119476
_version_ 1855521641939861504
author Moral, J.
Garcia-Lopez, M.T.
Gordon, A.
Ortega Beltran, A.
Puckett, R.D.
Tomari, R.
Gradziel, T.M.
Michailides, T.
author_browse Garcia-Lopez, M.T.
Gordon, A.
Gradziel, T.M.
Michailides, T.
Moral, J.
Ortega Beltran, A.
Puckett, R.D.
Tomari, R.
author_facet Moral, J.
Garcia-Lopez, M.T.
Gordon, A.
Ortega Beltran, A.
Puckett, R.D.
Tomari, R.
Gradziel, T.M.
Michailides, T.
author_sort Moral, J.
collection Repository of Agricultural Research Outputs (CGSpace)
description Aflatoxin contamination of almond kernels, caused by Aspergillus flavus and A. parasiticus, is a severe concern for growers because of its high toxicity. In California, the global leader of almond production, aflatoxin can be managed by applying the biological control strain AF36 of A. flavus and selecting resistant cultivars. Here, we classified the almond genotypes by K-Means cluster analysis into three groups (susceptible [S], moderately susceptible [MS], or resistant [R]) based on aflatoxin content of inoculated kernels. The protective effects of the shell and seedcoat in preventing aflatoxin contamination were also examined. The presence of intact shells reduced aflatoxin contamination >100-fold. The seedcoat provided a layer of protection but not complete protection. In kernel inoculation assays, none of the studied almond genotypes showed a total resistance to the pathogen. However, nine traditional cultivars and four advanced selections were classified as R. Because these advanced selections contained germplasm derived from peach, we compared the kernel resistance of three peach cultivars to that shown by kernels of an R (Sonora) and an S (Carmel) almond cultivar and five pistachio cultivars. Overall, peach kernels were significantly more resistant to the pathogen than almond kernels, which were more resistant than pistachio kernels. Finally, we studied the combined effect of the cultivar resistance and the biocontrol strain AF36 in limiting aflatoxin contamination. For this, we coinoculated almond kernels of R Sonora and S Carmel with AF36 72 h before or 48 h after inoculating with an aflatoxin-producing strain of A. flavus. The percentage of aflatoxin reduction by AF36 strain was greater in kernels of Carmel (98%) than in those of Sonora (83%). Cultivar resistance also affected the kernel colonization by the biological control strain. AF36 strain limited aflatoxin contamination in almond kernels even when applied 48 h after the aflatoxin-producing strain. Our results show that biocontrol combined with the use of cultivars with resistance to aflatoxin contamination can result in a more robust protection strategy than the use of either practice in isolation.
format Journal Article
id CGSpace119476
institution CGIAR Consortium
language Inglés
publishDate 2022
publishDateRange 2022
publishDateSort 2022
publisher Scientific Societies
publisherStr Scientific Societies
record_format dspace
spelling CGSpace1194762025-12-08T09:54:28Z Resistance to aspergillus flavus and aspergillus parasiticus in almond advanced selections and cultivars and its interaction with the aflatoxin biocontrol strategy Moral, J. Garcia-Lopez, M.T. Gordon, A. Ortega Beltran, A. Puckett, R.D. Tomari, R. Gradziel, T.M. Michailides, T. aflatoxins almonds aspergillus flavus aspergillus parasiticus cultivars disease resistance Aflatoxin contamination of almond kernels, caused by Aspergillus flavus and A. parasiticus, is a severe concern for growers because of its high toxicity. In California, the global leader of almond production, aflatoxin can be managed by applying the biological control strain AF36 of A. flavus and selecting resistant cultivars. Here, we classified the almond genotypes by K-Means cluster analysis into three groups (susceptible [S], moderately susceptible [MS], or resistant [R]) based on aflatoxin content of inoculated kernels. The protective effects of the shell and seedcoat in preventing aflatoxin contamination were also examined. The presence of intact shells reduced aflatoxin contamination >100-fold. The seedcoat provided a layer of protection but not complete protection. In kernel inoculation assays, none of the studied almond genotypes showed a total resistance to the pathogen. However, nine traditional cultivars and four advanced selections were classified as R. Because these advanced selections contained germplasm derived from peach, we compared the kernel resistance of three peach cultivars to that shown by kernels of an R (Sonora) and an S (Carmel) almond cultivar and five pistachio cultivars. Overall, peach kernels were significantly more resistant to the pathogen than almond kernels, which were more resistant than pistachio kernels. Finally, we studied the combined effect of the cultivar resistance and the biocontrol strain AF36 in limiting aflatoxin contamination. For this, we coinoculated almond kernels of R Sonora and S Carmel with AF36 72 h before or 48 h after inoculating with an aflatoxin-producing strain of A. flavus. The percentage of aflatoxin reduction by AF36 strain was greater in kernels of Carmel (98%) than in those of Sonora (83%). Cultivar resistance also affected the kernel colonization by the biological control strain. AF36 strain limited aflatoxin contamination in almond kernels even when applied 48 h after the aflatoxin-producing strain. Our results show that biocontrol combined with the use of cultivars with resistance to aflatoxin contamination can result in a more robust protection strategy than the use of either practice in isolation. 2022-02-01 2022-05-05T12:39:06Z 2022-05-05T12:39:06Z Journal Article https://hdl.handle.net/10568/119476 en Limited Access Scientific Societies Moral, J., Garcia-Lopez, M.T., Gordon, A., Ortega-Beltran, A., Puckett, R.D., Tomari, R., ... & Michailides, T. (2022). Resistance to aspergillus flavus and aspergillus parasiticus in almond advanced selections and cultivars and its interaction with the aflatoxin biocontrol strategy. Plant Disease, 106(2), 504-509.
spellingShingle aflatoxins
almonds
aspergillus flavus
aspergillus parasiticus
cultivars
disease resistance
Moral, J.
Garcia-Lopez, M.T.
Gordon, A.
Ortega Beltran, A.
Puckett, R.D.
Tomari, R.
Gradziel, T.M.
Michailides, T.
Resistance to aspergillus flavus and aspergillus parasiticus in almond advanced selections and cultivars and its interaction with the aflatoxin biocontrol strategy
title Resistance to aspergillus flavus and aspergillus parasiticus in almond advanced selections and cultivars and its interaction with the aflatoxin biocontrol strategy
title_full Resistance to aspergillus flavus and aspergillus parasiticus in almond advanced selections and cultivars and its interaction with the aflatoxin biocontrol strategy
title_fullStr Resistance to aspergillus flavus and aspergillus parasiticus in almond advanced selections and cultivars and its interaction with the aflatoxin biocontrol strategy
title_full_unstemmed Resistance to aspergillus flavus and aspergillus parasiticus in almond advanced selections and cultivars and its interaction with the aflatoxin biocontrol strategy
title_short Resistance to aspergillus flavus and aspergillus parasiticus in almond advanced selections and cultivars and its interaction with the aflatoxin biocontrol strategy
title_sort resistance to aspergillus flavus and aspergillus parasiticus in almond advanced selections and cultivars and its interaction with the aflatoxin biocontrol strategy
topic aflatoxins
almonds
aspergillus flavus
aspergillus parasiticus
cultivars
disease resistance
url https://hdl.handle.net/10568/119476
work_keys_str_mv AT moralj resistancetoaspergillusflavusandaspergillusparasiticusinalmondadvancedselectionsandcultivarsanditsinteractionwiththeaflatoxinbiocontrolstrategy
AT garcialopezmt resistancetoaspergillusflavusandaspergillusparasiticusinalmondadvancedselectionsandcultivarsanditsinteractionwiththeaflatoxinbiocontrolstrategy
AT gordona resistancetoaspergillusflavusandaspergillusparasiticusinalmondadvancedselectionsandcultivarsanditsinteractionwiththeaflatoxinbiocontrolstrategy
AT ortegabeltrana resistancetoaspergillusflavusandaspergillusparasiticusinalmondadvancedselectionsandcultivarsanditsinteractionwiththeaflatoxinbiocontrolstrategy
AT puckettrd resistancetoaspergillusflavusandaspergillusparasiticusinalmondadvancedselectionsandcultivarsanditsinteractionwiththeaflatoxinbiocontrolstrategy
AT tomarir resistancetoaspergillusflavusandaspergillusparasiticusinalmondadvancedselectionsandcultivarsanditsinteractionwiththeaflatoxinbiocontrolstrategy
AT gradzieltm resistancetoaspergillusflavusandaspergillusparasiticusinalmondadvancedselectionsandcultivarsanditsinteractionwiththeaflatoxinbiocontrolstrategy
AT michailidest resistancetoaspergillusflavusandaspergillusparasiticusinalmondadvancedselectionsandcultivarsanditsinteractionwiththeaflatoxinbiocontrolstrategy