WP 4 Field experiments
with artificial Fusarium
inoculation
Introduction
Fixed conditions
Methods and traits for discussion
Details of methods
AVEQ meeting CF 18.09.07
Salmon pink discoloration of husk und kernels after inoculation with
F. culmorum
AVEQ meeting CF 18.09.07
Field experiments with artificial
Fusarium inoculation
Aim
Evaluation/screening of genetic ressources for resistance to Fusarium ssp. and/or mycotoxin accumulation
These traits are quantitativ inherited and influenced by environment and other traits as plant height, lodging, panicle length, hull content etc.
AVEQ meeting CF 18.09.07
WP4 Field experiments with artificial Fusarium
inoculation
Fixed conditions
• 300 Accessions/a.
• 10 standard cultivars,
replicated 5 fold,
(augmented
design)
AVEQ meeting CF 18.09.07
Methods and traits
need to be discussed
- Design and number of replications and
Plot size (2 m2 or less)
- Inoculation method
- Fusarium ssp. for inoculation
- Method of harvesting and sample preparation
AVEQ meeting CF 18.09.07
Traits of evaluation, need to be discussed(Leaf index and number of kernel per spikelet were deleted)
1. heading date,
2. panicle density per m2,
3. crop height,
4. distance between panicle and flag leaf
5. panicle shape,
6. panicle length,
7. infection of panicles with Fusarium
8. lodging at harvest
9. thousand kernel weight (TGW),
10. test weight
11. Fusarium-infection of seeds
12. hull content (HUC)
AVEQ meeting CF 18.09.07
Design, plot size and number of replications
Augmented design or randomised block design ?
Details of methods
Augmented design at four climatically different locations
(Germany, Czech Republik, Romania, Italy)
• Comparisons with standard cv.s should give a good evaluation at least
susceptibility in accessions tested.
• Number of plots manageable and lower border effects in comparison with
smaller plots in a randomised design.
• Accessions grouped for crop height and heading date
AVEQ meeting CF 18.09.07
Inoculation method
• Replicated Spraying of spore suspension over the plots
with a portable sprayer (during or after flowering, 105-106 spores
per ml + 0.1ml/l Tween 20; 50ml/m2 , at 7 p.m., high air humidity, low
wind)
• alternatively/additionally: Scattering infected seeds
(6g/m2, before heading) within the plots (more natural)
• After inoculation and dry weather conditions: Irrigation, if available
Details of methods
AVEQ meeting CF 18.09.07
Inoculum:
Mycotoxin profile dependent from the Fusarium strain and Fusarium
species (no correlation to aggressiveness), high variability within and
between species
Tab. 1 according to Langseth et al. (1999)
Details of methods
AVEQ meeting CF 18.09.07
Fusarium species
Isolate NIV DON T-2; HT-2 Zea Monili-formin
culmorum 1163 14 - - 120
culmorum 1028 - 45 - 370
graminearum 1104 - 290 - 1960
poae F13 In other studies
- - 0,04
sporotrichioides 1079-15 - - 72 -
avenaceum 1035-18 - - - 0,03 1100
•Low host specialisation in F. graminearum, F.
culmorum and F. avenaceum
•Adaptation of Fusarium ssp. to local climatic conditions
and different aggressiveness.
Consequence for screening in WP4:
Usage of local defined mixtures of mycotoxin producing strains of F.
graminearum, F. culmorum, F. sporotricioides and F. avenaceum for
inoculation
disadvantage: competition between Fusarium strains results in reduced
aggressiveness and lower mycotoxin accumulation (Midaner et al. 2004)
Details of methods
AVEQ meeting CF 18.09.07
Traits of evaluation, need to be discussed and fixed
• heading date = day in June or July
• leaf index ??
• panicle density per m2, counting 1 m of two rows,
appropriate germination presumed
• crop height in cm (after flowering but before
lodging) Average height of the plants from ground to
top of panicle, excluding awns.
• panicle length in cm
Details of methods
AVEQ meeting CF 18.09.07
Infection of panicles with Fusarium:
Usually there is low or no visual scab, but it have to be
checked. 1=no infection ... 9=all spikelets and panicles
are infected
Lodging prior harvest: 1=no lodging…9= 100%lodging
Number of kernels per spikelet ???
Thousand kernel weight (TGW) (might be reduced due to
Fusarium infection) 3 x 100 unsorted kernel
Test weight in grams per hectoliter
Details of methods
AVEQ meeting CF 18.09.07
Percent Fusarium infected kernels by sorting 3 x 100 kernels (from TKW-measurement)
Three classes:1. sound
2. suspicious infected, grey tips
3. FDK= Fusarium damaged kernels, discoloured, smaller,
Details of methods
AVEQ meeting CF 18.09.07
influence on the assessment of Fusarium infection of seeds:
Color of the lemma as in BSA/IBPGR
Details of methods
AVEQ meeting CF 18.09.07
influence on the assessment of Fusarium infection of seeds:
Color of the lemma as in BSA/IBPGR
hull content (HUC):• Weigh out 100g seeds of equal moisture content,
• air-pressure dehuller, 8 at, 4 min,
• note the weight of kernels and hulls;
• score of undehulled kernels
• Additionally: score of proportion of discoloured groats
Details of methods
AVEQ meeting CF 18.09.07
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