Post on 15-Dec-2015
Corn residue can favor certain diseases
What is the most practical way to kill out pathogens surviving in corn residue?
Spores of gray leaf spot fungus
Northern leaf blight
Image by K. Leonard and E. G. SuggsCourtesy of the American Phytopathological Society
Susceptible and resistant reactions to Northern leaf blight
Image by K. Leonard and E. G. SuggsCourtesy of the American Phytopathological Society
Susceptiblehybrid
Chlorotic lesionReaction (Ht resistance)
Factors that EnhanceCorn Stalk Rots
•High plant populations
•High nitrogen rates
•High levels of leaf disease
Maximum Fumonisin Levels Recommended by US FDA
Intended use
Max fumonisins (FB1+FB2+FB3)
Equids and rabbits 5 ppm(no more than 20% of diet)
Swine and catfish 20 ppm(no more than 50% of diet)
Human foods 2-4 ppm
FDA Aflatoxin Action Levels
Action Level (parts per billion)
Commodity Species
0.5 Milk Humans
20 Any food except milk
Humans
20 Feed Livestock*
*Exceptions for breeding cattle, breeding swine, mature poultry, finishing swine, & finishing beef cattle
Factors That Enhance Corn Ear and Kernel Rots and Preharvest Mycotoxin
Accumulation
• Hot, dry weather during silking or grain fill
• Delayed harvest
• Injury to kernels (insects, birds)
• Hybrids with ears at maturity that are:
- upright
- incomplete husk coverage
Reducing risks of mycotoxins in storage
• Adjust combine for minimum kernel damage• Dry below 15.5% within 24-48 hours of shelling• Clean storage facilities and control insects• Aerate and check for heating and crusting
Testing corn samples
UK Grain Quality Testing LabAttn: Michael D. Montross
Biosystems & Agricultural Engineering
128 Barnhart Bldg.
University of Kentucky
Lexington, KY 40546-0276
Voice: (859) 257-3000 X106
Fax: (859) 257-5671
Email: montross@baeuky.edu
Headline 6 fl oz, Quilt 14 fl oz, Stratego 10 oz
63 out of 168 = 38% of the time had a yield increase of 6 bu/A or greater.
Mean = 3 bu/A increase over the untreated
-35-30-25-20-15-10
-505
1015202530
Location or Hybrid
Yie
ld d
iffe
ren
ce f
rom
un
trea
ted
(b
u/A
)
-30
-20
-10
0
10
20
30
40
50
60
Fu
ng
icid
e yi
eld
ad
van
tag
e (b
u/a
cre)
Overall Yield ResponseUniversity (68) and On-Farm (121) Trials
*Assumes $3.75/bu corn and $20/ac for fungicide. Break-even response = 5.3 bu/ac
Overall yield advantage: 8.7 bu/acPercent wins: 79%Economically beneficial*: 60%Average net return: $12.63/ac
(121 hybrids from 20 companies)
PIONEER SUMMARY