Full Length Research Paper

A RAMP marker linked to the tobacco black shank resistant gene

X. Z. Liu¹, Y. M. Yang¹, C. S. He², H. L. Li³ and H. Y. Zhang^1*

¹Biotechnology Laboratory, Southwest Forestry College, Kunming, 650224 Yunnan Province, People’s Republic of China.

²The South Center of Tobacco Breeding Research of China, Yuxi, 653100 Yunnan, People’s Republic of China.

³Tropical Crops Genetic Resources Institute, Chinese Academy of Tropical Agriculture Sciences, Dangzhao, Hainan, People’s Republic of China, 571737.

*Corresponding author. E-mail: hanyaoz@163.com. Tel: +86-0871-3863022 Fax: +86-0871-3862178.

Accepted 17 March, 2009

Bulk segregant analysis (BSA) and randomly amplified microsatellite polymorphism (RAMP) were employed to analyze F₂ individuals of the Yunyan 317×Hubei 517 to screen and characterize molecular markers linked to black shank resistant gene. A total of 800 arbitrary decamer oligonucleotide primer-pairs were used for RAMP analysis. Primer pair GT (CA) ₄/S89, producing one RAMP marker GT (CA) ₄/S89₅₅₀, was tightly linked to the black shank resistant gene. Results of Southern blot suggest that the fragment GT (CA) ₄/S89₅₅₀ was existed in Yunyan 317 and resistant plants, and absent in Hubei 517. Linkage analysis was carried out using marker GT (CA) ₄/S89₅₅₀ on 752 black shank high-resistant individuals of F₂ progenies from crossing between Yunyan 317 and Hubei 517. Our results indicated that the genetic distances between GT (CA) ₄/S89₅₅₀ and black shank resistant gene was 1.4cM.

Key words: Tobacco, black shank resistant gene, RAMP, molecular marker.