HAL Id: hal-02746711
https://hal.inrae.fr/hal-02746711
Submitted on 3 Jun 2020
HAL is a multi-disciplinary open access archive for the deposit and dissemination of sci- entific research documents, whether they are pub- lished or not. The documents may come from teaching and research institutions in France or abroad, or from public or private research centers.
L’archive ouverte pluridisciplinaire HAL, est destinée au dépôt et à la diffusion de documents scientifiques de niveau recherche, publiés ou non, émanant des établissements d’enseignement et de recherche français ou étrangers, des laboratoires publics ou privés.
Saprophytic survival of Fusarium graminearum in crop residues
Johann Leplat, Laurent Falchetto, Pierre Mangin, Cécile Héraud, Elodie Gautheron, Nadine Gautheron, Veronique Edel Hermann, Christian Steinberg
To cite this version:
Johann Leplat, Laurent Falchetto, Pierre Mangin, Cécile Héraud, Elodie Gautheron, et al.. Sapro- phytic survival of Fusarium graminearum in crop residues. 12. European Fusarium Seminar, May 2013, Bordeaux, France. 2013, ‘Fusarium – Mycotoxins, Taxonomy, Genomics, Biosynthesis, Pathogenicity, Resistance, Disease control’. �hal-02746711�
Winter disease development
Development stage 2
nodes
Development on spike
Seed-borne Inoculum
Soil-borne inoculum
Soil surface inoculum
Saprophytic survival of Fusarium graminearum in crop residues
Conclusion :
There is no early indicators enabling to predict and control FHB.
Part of the life cycle of F. graminearum relies on a saprotrophic phase during which the fungus seems to exhibit weakness.
Therefore, the management of crop residues appears as the key point to control the development of FHB. A strong emphasis should be placed on the biological decomposition of crop residues at the soil surface or/and
on the use of suppressive intermediate crops such as mustard to limit the soil inoculum potential of saprotrophic F. graminearum.
Saprophytic survival of Fusarium graminearum in soil in presence of various crop residues
Population dynamics of F. graminearum were assessed in controlled conditions (small microcosms) by Q PCR measurements
J. Leplat1, L. Falchetto2, P. Mangin2, C. Heraud1, E. Gautheron1, N. Gautheron1, V. Edel-Hermann1, C. Steinberg1
1 INRA, UMR1347 Agroécologie 17 rue Sully, BP 86510, F-21000 Dijon, France. http://www6.dijon.inra.fr/umragroecologie
2 INRA, UE Domaine d’Epoisses, F-21110 Bretenières, France Email : christian.steinberg@dijon.inra.fr
This poster reports part of a PhD work (J. Leplat) funded by the Vitagora–FUI programme Farine+ 2007–11
10 100 1000 10000 100000 1000000 10000000
0 10 20 30 40 50 60 70 80
Days
10 100 1000 10000 100000 1000000 10000000
0 10 20 30 40 50 60 70 80
Days
Number of DNA copies.g-1 of matrix Number of DNA copies.g-1 of matrix
Relative contribution of different sources of
inoculum in the development of Fusarium diseases
Soil
No crop residues Seed-borne
inoculum
Buried crop residues Soil-borne
inoculum
Air-borne inoculum
Crop residues on the surface
Weeds,
Adjacent plots
Winter development of the disease
Development
stage 2 nodes Development of the disease on spike
C/N 14
116
Fusarium Head Blight (FHB) is one of the most important disease altering wheat crops.
A field experiment was conducted i) to better understand the saprotrophic development of Fusarium graminearum and its consequences on FHB, ii) to characterize the relative importance of the different sources of FHB inoculum and the accumulation of mycotoxins in grains and subsequently, iii) to determine early indicators of future disease development on ears and accumulation of mycotoxins in grains.
No correlation
Relationship between early symptoms and the severity of Fusarium Head Blight
- No correlation between early symptoms and FHB => No early indicators
- Climate plays a decisive role
- Image analyses (not shown here) of spikes and spikelets revealed a positive correlation between symptoms and mycotoxin contents - Air borne inoculum was not taken into account in this study.
- Crop residues left on the surface are the main source of FHB symptoms => they need a specific focus !
- Three wheat varieties (susceptible to resistant to FHB)
- Various sources of inoculum of F. graminearum (seed, soil, buried and non buried crop residues)
- 3 replicates/treatment, bioassay was performed two consecutive years
- Measurements (field and lab) were carried out throughout the duration of the culture
Symptoms No symptoms
Disinfected soil + wheat residues
Disinfected soil without residues
Natural soil + wheat residues
Natural soil without residues
Soil + Maize residues Soil + Wheat residues Soil + Rape residues Soil without residues
Soil + Mustard residues Soil + Alfalfa residues
The soil-borne biota limits F. graminearum development The wheat residues provide exploitable resources for F.
graminearum and consequently promote its saprotrophic survival.
The exploitation of trophic and spatial resources provided by the crop
residues depends on their nature (previous crop and C/N) : maize stubbles provide a greater carrying capacity than wheat straw and rapeseed residues while mustard has a suppressive effect for the fungus.
The growth promoting effect of Alfalfa for F. graminearum is likely due to the rich N content of the residues but this effect is short-lived because its
decomposition is probably also facilitated by the presence of N
Leplat, J., H. Friberg, M. Abid, and C. Steinberg. 2013.
Survival of Fusarium graminearum, the causal agent of Fusarium head blight. A review. Agronomy for Sustainable Development 33:97-111.
