Submitted to: Rice Technical Working Group Meeting Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: January 1, 2006
Publication Date: February 15, 2006
Citation: Jia, Y., Gealy, D.R., Lin, M.J., Wu, L., Black, H.L. 2006. Carolina foxtail (alopecurus carolinianus): susceptibility and suitability as an alternate host to rice blast disease (p. grisea) [abstract]. In: Rice Technical Working Group Meeting Proceedings, Houston, Texas, February 29-March 2, 2006. 2006.CDROM. Technical Abstract: Carolina foxtail (Alopecurus carolinianus), a common cool season weed of intermittently flooded soils, was found to host rice blast fungus (Magnaporthe grisea) in the greenhouse. A collection of Carolina foxtail over four years in Arkansas was inoculated with a range of predominant races of rice blast fungus in the USA. Irregular, yellow and brown lesions without obvious gray centers were observed after each inoculation with M. grisea isolates. Differences in these lesions were not observed among foxtail collections over the years. Consistently, these disease-like lesions that were significantly different from a typical blast lesion were evident after the artificial inoculation in the greenhouse. P. grisea races that differed in their pathogenicity toward rice cultivars also displayed differences in lesion development on Carolina foxtail. The most virulent isolate on rice cultivars also produced lesions most rapidly on Carolina foxtail. These lesions developed sooner on Carolina foxtail than the most susceptible rice cultivars tested, including the California cultivar, M202. Conversely, P. grisea isolates cultured from these lesions in the infected Carolina foxtail also caused typical disease symptoms of blast indicating that they were also pathogenic toward rice cultivars. Susceptibility and suitability of Carolina foxtail as an alternate host to rice blast disease (P. grisea) is discussed.