Since its first report almost 200 years ago, fire blight, caused by the gram-negative bacterium Erwinia amylovora, has threatened apple and pear production globally. Identifying novel genes and their functional alleles is a prerequisite to developing apple cultivars with enhanced fire blight resistance. Here, we report 13 strain-specific and environment-dependent minor QTLs linked to fire blight resistance from a segregating Malus sieversii × Malus × domestica mapping population. Interval mapping at 95% confidence and Kruskal–Wallis analysis at P value = 0.005 were used to identify QTLs for three strains of E. amylovora differing in virulence and pathogenicity. The QTLs identified explain a small to moderate part of resistance variability, and a majority was not common between years or E. amylovora strains. These QTLs are distributed in eight linkage groups of apples and comparison of their map position to previously identified fire blight resistance QTLs indicates that most are novel loci. Interaction between experimental conditions in the greenhouse and field, and between years, and differences in virulence levels of strains might be responsible for strain- and year-specific QTLs. The QTLs identified on LG10 for strain Ea273 in 2011 and strain LP101 in 2011, and on LG15 for strain LP101 could be the same QTLs identified previously with strain CFBP1430 in cultivar “Florina” and “Co-op16 × Co-op17” mapping population, respectively. We discuss the potential impact of newly identified minor fire blight QTLs and major gene-based resistance on the rate of mutation in pathogen populations to overcome resistance and durability of resistance

Desnoues, E.; Norelli, J.; Aldwinckle, H.; Wisniewski, M.; Evans, K.; Malnoy, M.; Khan, A. (2018). Identification of novel strain-specific and environment-dependent minor QTLs linked to fire blight resistance in apples. PLANT MOLECULAR BIOLOGY REPORTER, 36 (2): 247-256. doi: 10.1007/s11105-018-1076-0 handle: http://hdl.handle.net/10449/43953

Identification of novel strain-specific and environment-dependent minor QTLs linked to fire blight resistance in apples

Malnoy, M.
Penultimo
;
2018-01-01

Abstract

Since its first report almost 200 years ago, fire blight, caused by the gram-negative bacterium Erwinia amylovora, has threatened apple and pear production globally. Identifying novel genes and their functional alleles is a prerequisite to developing apple cultivars with enhanced fire blight resistance. Here, we report 13 strain-specific and environment-dependent minor QTLs linked to fire blight resistance from a segregating Malus sieversii × Malus × domestica mapping population. Interval mapping at 95% confidence and Kruskal–Wallis analysis at P value = 0.005 were used to identify QTLs for three strains of E. amylovora differing in virulence and pathogenicity. The QTLs identified explain a small to moderate part of resistance variability, and a majority was not common between years or E. amylovora strains. These QTLs are distributed in eight linkage groups of apples and comparison of their map position to previously identified fire blight resistance QTLs indicates that most are novel loci. Interaction between experimental conditions in the greenhouse and field, and between years, and differences in virulence levels of strains might be responsible for strain- and year-specific QTLs. The QTLs identified on LG10 for strain Ea273 in 2011 and strain LP101 in 2011, and on LG15 for strain LP101 could be the same QTLs identified previously with strain CFBP1430 in cultivar “Florina” and “Co-op16 × Co-op17” mapping population, respectively. We discuss the potential impact of newly identified minor fire blight QTLs and major gene-based resistance on the rate of mutation in pathogen populations to overcome resistance and durability of resistance
Fire blight
Erwinia amylovora
Malus domestica
Host resistance
QTL mapping
Durable resistance
Settore AGR/07 - GENETICA AGRARIA
2018
Desnoues, E.; Norelli, J.; Aldwinckle, H.; Wisniewski, M.; Evans, K.; Malnoy, M.; Khan, A. (2018). Identification of novel strain-specific and environment-dependent minor QTLs linked to fire blight resistance in apples. PLANT MOLECULAR BIOLOGY REPORTER, 36 (2): 247-256. doi: 10.1007/s11105-018-1076-0 handle: http://hdl.handle.net/10449/43953
File in questo prodotto:
File Dimensione Formato  
Desnoues2018_Article_IdentificationOfNovelStrain-Sp.pdf

solo utenti autorizzati

Licenza: Tutti i diritti riservati (All rights reserved)
Dimensione 1.69 MB
Formato Adobe PDF
1.69 MB Adobe PDF   Visualizza/Apri   Richiedi una copia

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/10449/43953
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 25
  • ???jsp.display-item.citation.isi??? 24
social impact