Differences in Active Defense Responses of Two Gossypium barbadense L. Cultivars Resistant to Fusarium oxysporum f. sp. vasinfectum Race 4.
J Agric Food Chem
; 66(49): 12961-12966, 2018 Dec 12.
Article
in En
| MEDLINE
| ID: mdl-30380850
ABSTRACT
A highly virulent race 4 genotype of Fusarium oxysporum f. sp. vasinfectum (Fov) was identified for the first time in the western hemisphere in 2002 in cotton fields in the San Joaquin Valley of California. The Gossypium barbadense L. cotton cultivars 'Seabrook Sea Island 12B2' ('SBSI') and 'Pima S-6' are resistant to Fov race 4. Active defense responses were quantitated by monitoring the accumulation of antimicrobial terpenoids (i.e., phytoalexins) in inoculated stem stele tissue in these cultivars. The increase in the concentration of the most toxic phytoalexins was statistically faster after 24 h in 'SBSI' compared to 'Pima S-6'. The sesquiterpenoid hemigossylic acid lactone, which was observed for the first time in nature, also accumulated in diseased plants. Neither hemigossylic acid lactone nor the disesquiterpenoids gossypol, gossypol-6-methyl ether, and gossypol-6,6'-dimethyl ether showed toxicity to Fov. Segregation of F2 progeny from 'SBSI' × 'Pima S-6' crosses gave a few highly susceptible plants and a few highly resistant plants, indicating separate genes for resistance in the two cultivars.
Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Plant Diseases
/
Gossypium
/
Disease Resistance
/
Fusarium
Aspects:
Determinantes_sociais_saude
Country/Region as subject:
America do norte
Language:
En
Journal:
J Agric Food Chem
Year:
2018
Document type:
Article
Affiliation country: