Gene in Cotton Confers High and Broad Resistance to Bacterial Blight and Conditions High Amounts of Sesquiterpenoid Phytoalexins.

Bacterial blight resistance gene has received little attention since it was first described in 1950. A near-isogenic line (NIL) of cotton, Ac, was generated in an otherwise bacterial-blight-susceptible 'Acala 44' background. The introgressed locus in Ac conferred strong and broad-spectrum resistance to bacterial blight.

Pyramiding B genes in cotton achieves broader but not always higher resistance to bacterial blight.

Near-isogenic lines of upland cotton (Gossypium hirsutum) carrying single, race-specific genes B4, BIn, and b7 for resistance to bacterial blight were used to develop a pyramid of lines with all possible combinations of two and three genes to learn whether the pyramid could achieve broad and high resistance approaching that of L. A. Brinkerhoff's exceptional line Im216.

Four near-isogenic lines of cotton with different genes for bacterial blight resistance.

ABSTRACT The development and genetic characterization of four near-isogenic lines (NILs) of cotton (Gossypium hirsutum) is described herein. Each line contains a single, but different, gene for resistance to bacterial blight caused by Xanthomonas campestris pv. malvacearum.