ARS | Publication request: REACTION OF SELECT TEPARY BEAN TO ASHY STEM BLIGHT AND FUSARIUM WILT

Submitted to: HortScience
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: July 2, 1997
Publication Date: N/A

Interpretive Summary: Fusarium wilt and ashy stem blight are two diseases which adversely effect dry-edible beans. Yield losses caused by these two diseases and the costs incurred for the chemical pesticides used to control them create an annual economic hardship for growers. We searched for new sources of resistance to these two diseases. Three tepary bean germplasm were found to possess high levels of resistance to both ashy stem blight and fusarium wilt. These plant materials will be useful in the development of future bean cultivars with improved disease resistance. Disease resistant cultivars will yield more, and ensure a safer food product and cleaner environment through reduced pesticide use, which will be beneficial to both consumers and growers alike.

Technical Abstract: Cultivated tepary bean (Phaseolus acutifolius A. Gray var. latifolius Freeman) has received considerable interest as a crop for dryland production regions around the world. Successful tepary bean production will depend partly upon its resistance to endemic diseases. Fourteen select tepary bean lines were evaluated in the field and by rice-seed inoculation for resistance to ashy stem blight [Macrophomina phaseolina (Tassi) Goid.] and by a root-clip inoculation method for resistance to Fusarium wilt [Fusarium oxysporum Schlechtend.:Fr. f. sp. phaseoli J.B. Kendrick and W.C. Synder) (Fop)]. Three lines, Mex-114, PI 440806-s, and PI 321637-s, exhibited high levels of resistance to both pathogens and their diseases. These reactions combined with known resistances to other pathogens and their diseases will allow identification of multiple disease resistant tepary bean germplasm for use in different production regions and dbreeding programs.