Skip to main content
ARS Home » Plains Area » Lincoln, Nebraska » Wheat, Sorghum and Forage Research » Research » Publications at this Location » Publication #311621
Title: Presence of Fusarium graminearum in air associated with sorghum fields

Author
item Funnell-Harris, Deanna
item Sattler, Scott
item Graybosch, Robert

Submitted to: National Fusarium Head Blight Forum
Publication Type: Abstract Only
Publication Acceptance Date: 12/7/2014
Publication Date: 12/7/2014
Citation: Funnell-Harris, D.L., Sattler, S.E., Graybosch, R.A. 2014. Presence of Fusarium graminearum in air associated with sorghum fields. National Fusarium Head Blight Forum Proceedings. p.63.

Interpretive Summary:

Technical Abstract: Sorghum can be included in crop rotations with wheat. However, there are no known reports on the effects of sorghum grown in rotation with wheat on the epidemiology of head scab caused by Fusarium graminearum. Conidia in air samples within two sorghum fields were collected by passive spore trapping for two years at four plant stages (vegetative, anthesis, grain development or maturity) during the sorghum growing season. Spores were collected and germinated on a general fungal medium (potato dextrose agar; PDA) and a medium semi-selective for Fusarium spp. (pentachloronitrobenzene-containing agar; PCNB). Colonies cm-2 hr-1 on PCNB ranged from 31.0 to 85.7 percent of colonies cm-2 hr-1 on PDA, depending on environment and growth stage. A subsample of Fusarium isolates from PCNB traps were identified molecularly by comparing sequences from a portion of the translation elongation factor (TEF) 1a gene with those in the FUSARIUM-ID database (http://isolate.fusariumdb.org/index.php). Surprisingly, 26.8% were F. graminearum, the most numerous Fusarium species or genotype. Phylogenetic analyses of these isolates, as well as F. graminearum from sorghum leaf tissue and grain, using TEF, the rRNA internal transcribed spacer region and a portion of the histone-3 gene (H3), revealed that these isolates were highly similar to one another and to previously characterized F. graminearum isolates. Further research to determine whether isolates associated with sorghum production produce tricothecenes or zearalenone and are pathogenic to wheat, will need to be conducted to determine whether F. graminearum associated with sorghum production can affect head scab levels in wheat.