Submitted to: Plant Pathology Journal
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/6/2007
Publication Date: 6/1/2007
Citation: Erpelding, J.E. 2007. Inheritance of Anthracnose Resistance for the Sorghum Cultivar Redlan. Plant Pathology Journal. 6 (2): 187-190. Interpretive Summary: Anthracnose is one of the most important diseases of sorghum. The disease can be controlled through the use of resistant cultivars, but genetic variation within the pathogen population can overcome resistance in sorghum hybrids presently available to producers. To better understand and evaluate changes in the pathogen population, information is needed on the inheritance of resistance in sorghum cultivars. The anthracnose resistant sorghum cultivar, ‘Redlan’, has been used to evaluate pathogen variation, but no information is available on the genetics of disease resistance for Redlan. Thus, an evaluation was conducted to determine the genetic inheritance of anthracnose resistance in Redlan. Results of the evaluation indicated that foliar anthracnose resistance is controlled by a single dominant gene. Anthracnose can also cause infection in other tissues of the sorghum plant and resistance to anthracnose infection of the leaf midrib in Redlan was determined to be controlled by a single recessive gene. Evaluation of segregation data indicated that the two genes are not linked and would be inherited independently. For the development of anthracnose resistant sorghum hybrids, dominant sources of resistance are more desirable, since the resistant gene needs to be incorporated into only one of the parental breeding lines for resistance to be expressed in the hybrid.
Technical Abstract: Anthracnose occurs worldwide and is one of the most important diseases limiting sorghum production. The development of resistant varieties to control the disease is hindered by extensive variation in virulence for the pathogen. The sorghum cultivar, ‘Redlan’, has been used to evaluate virulence within and between pathogen populations, but no information is available on the genetic inheritance for anthracnose resistance in Redlan. To determine the inheritance of resistance in Redlan, a F2 population was developed and evaluated at the USDA-ARS Tropical Agriculture Research Station in Isabela, Puerto Rico in 2005. Results of the disease evaluation indicated that foliar anthracnose resistance observed in Redlan is controlled by a single dominant gene. Anthracnose infection of the leaf midrib was also observed in the F2 population and results indicate resistance for midrib infection is controlled by a single recessive gene. Segregation analysis, based on the frequency of recombinants for foliar and midrib resistance, indicated that the two genes are unlinked.