Phytopathogenic Fusarium species are the subject of three projects in our laboratory:

1. Epidemiology of Fusarium head blight in small-grain cereals

Since 2003 the Ministry of Consumer Protection, Environment and Agriculture (BMVEL) has been funding the development of an epidemiological model of Fusarium Head Blight (FHB). The goal is to establish a web-based tool which will predict the risk of FHB on a particular plot depending on cultivar, wheather, tillage and other factors and to help plant protection services and farmers reduce the contamination of grain with mycotoxins of Fusarium spp. It is a co-operative projects involving ZEP (programing), numerous plant protection institutions in Germany (supply of samples) and our institute (coordination, field trials and laboratory analysis).

Christoph Brandfass in our labotory has been contributing a substantial part of the project by establishing and applying real-time PCR assays for the quantification of Fusarium graminearum and Fusarium culmorum biomass in grain samples and plant residues, investigating conditions for ascospore production and discharge in the laboratory and performing field trials (the last two parts together with Dr. Joachim Weinert in our institute).

Christoph's results have so far been published in these contributions:

• Brandfaß, C.; Pöhler, I.; Weinert, J.; Karlovsky, P. (2004): Real-time PCR based methods for the detection of Fusarium graminearum and F. culmorum in wheat samples. 54. Deutsche Pflanzenschutztagung, Hamburg; Mitt. BBA 396; 221-222.
• Brandfaß, C.; Weinert, J.; Kleinhenz, B.; v. Tiedemann, A. and Karlovsky, P. (2005): Fusarium-Arten in Spindeln symptomatischer FHB-Ähren - Eine Bestimmung mit Hilfe der Real-time PCR als Grundlage für die Etablierung eines Prognosemodells. Phytomedizin 35 (2); 54-55.
• Brandfaß, C.; Weinert, J.; Kleinhenz, B.; v. Tiedemann, A. and P. Karlovsky (2005): Bestimmung der wichtigsten am Komplex der Ährenfusariose in der BRD beteiligten Fusarium-Arten mit Hilfe der Real-time PCR als Grundlage eines Prognosemodells. Phytomedizin, In press
• Weinert, J.; Kleinhenz, B.; Brandfaß, C.; Karlovsky, P. and A. v. Tiedemann (2005): Untersuchungen zum unterschiedlichen Auftreten von FHB und DON-Belastungen im Erntegut von Weizen als Grundlage eines Prognose- und Entscheidungsmodells. Phytomedizin, In press
• Brandfass, C.; Karlovsky, P. (2005): Simultaneous detection of Fusarium culmorum and F. graminearum in plant material by duplex PCR with melting curve analysis. (Submitted)

 

2. Secondary metabolites of Fusarium spp. infecting parasitic plants Striga hermontica

See also these photos

Striga hermontica is an economically important parasite on sorghum and maize in Africa. Biological control of Striga by phytopathogenic fungi has been suggested. Most fungi infecting Striga belong to the genus Fusarium. Rashid Ibrahim Mohukker (University of Khartoum, Sudan) has been isolating and characterizing fungal species from Striga in our laboratory since March 2005. After characterizing the isolates taxonomically, he will compare the phytotoxicity of culture supernatants in a Striga germination assay. The supernatants of most efficient isolates will be fractionated with the goal of identifying metabolites responsible for the effect.

On the photo you see Rashid (left) investigating fungal isolates under microscope and Wolfgang (right) who recently joined Arne and Astrid in their work on Verticillium in a project supervised by Dr. Hanno Wolf.

3. Infection of maize with Fusarium spp.

Sabine Nutz and Christof Bolduan are working on different projects on Fusarium in maize in close collaboration with breeding company KWS (Einbeck, Germany). Among the topics they persue are
(i) comparison of different method for the artification inoculation of maize with Fusarium graminearum and Fusarium verticillioides,
(ii) relatinship between visual rating, fungal biomass and mycotoxin content, and
(iii) the effect of agricotechnical practices of infection and mycotoxin content.
Sabine and Christoph use real-time PCR for the species-specific determination of fungal biomass. Furthermore, they analyze grain samples for mycotoxins deoxynivalenol, fumonisin B1 and zearalenone by HPLC-MS. Dr. Uli Hettwer supervises the analytical chemistry part while Christoph Brandfass, who played a crucial role in establishing real-time PCR assays for F. graminearum and F. culmorum in our laboratory, is responsible for the DNA-analytical part. In addition to these two species, Sabine is developing a real-time PCR assay for F. verticillioides based on published species-specific sequences.

 

Molecular Phytopathology Institute of Plant Pathology and Plant Protection Grisebachstrasse 6, 37077 Goettingen, Germany FAX: +49 551 3912919