wireworm presentation slideshow
TRANSCRIPT
Wireworm management in grain production
Dr. Christine Noronha Agriculture and Agri-food Canada, Charlottetown
Research and Development Centre
Presentation to ACORN November 24, 2015 - PEI
What are Wireworms • Larvae of click beetles. • Several species cause crop damage. • An emerging pest worldwide. • Affect a wide variety of crops. • Can render root crops unmarketable. • Very limited means of control.
Lifecycle of Wireworms
They pupate in the soil and emerge as adults in the spring. Lifecycle 5 years
Spring-early summer Adults lay 100-200 eggs in the soil
Spring – damage seeds and seedling roots
Later Fall- hibernate in the soil. Return to the surface in the spring.
Click beetles
Larvae
Fall damage root crops
May 2010 eggs
May 2011
May 2012
May 2013
May 2014
May 2015eggs
Yr.1 L
Yr.2 L
Yr.3 L
Yr.4 L
Yr.5 L – pupa -Adults hibernate
Hibernate
Hibernate
Hibernate
Hibernate
Once a field is infested it will be remain so until wireworms are killed
Larval Duration
1 female lays 100-200 eggs
If only 8 larvae survive to become adults in year five, with 4 females and four males each females produces 100-200 eggs Five years later
Ten years later
Population Increase
2012 2013 2014 2015 2016 2017
15 1000
5 200
2 50
6 500
1000 3000
Yr1 1000 Yr2 Yr3 Yr4 yr5
Yr1 200 Yr2 1000 Yr3 Yr4 Yr5
Yr1 50 Yr2 200 Yr3 1000 Yr4 Yr5
Yr1 0 Yr2 50 Yr3 200 Yr4 1000 Yr5
Yr1 500 Yr2 0 Yr3 50 Yr4 200 Yr5 1000
Yr1 3000 Yr2 500 Yr3 0 Yr4 50 Yr5 200
Damage can be worse in some years and less is others in newly infested fields?
• Agriotes sputator (NS, NB and PEI • Agriotes obscurus PEI and NS • Agriotes lineatus PEI and NS
• Hypnoidus abbreviatus • Ctenicera pulchra • Dalopius sp
European Species
Other species
48 species of click beetles in PEI, 98 in NB and 101 NS
Click Beetle Species
Where do they prefer to lay their eggs Sod fields
Pasture fields
Under-seeded fields
Undisturbed fields with green plant material are preferred
Adults will also lay eggs in bare soil, egg survival may be compromised
Monitoring Click Beetles
• Wireworm populations have been closely monitored in PEI using pheromone traps.
• Pheromones are chemical produced by females to attract males.
• Pheromone are available for some of the European species.
• Traps collect only male beetles.
Range of beetle
numbers
Prince County No. of Farms
Queen County No. of Farms
Kings county No. of Farms
2009 2012 2014 2009 2012 2014 2009 2012 2014
0 4 4 1 0 0 0 2 1 0 1-‐10 16 25 2 8 6 0 10 12 0 11-‐50 7 5 7 7 4 3 3 7 2 51-‐100 0 2 1 1 3 3 0 0 1 101-‐500 0 2 4 2 5 4 0 0 2 501-‐1000 0 0 2 0 5 2 0 0 1 >1000 0 1 0 0 3 5 0 0 0
Total # of beetles
214 1969 2812 1308 10,438 14,152 76 197 1298
Total per trap
7.9 50 83 72 401.46 416.23 5.4 9.8 108
Table 1. Comparisons of the number of farms with beetles numbers ranging for 0 - >1000 in 2009 and 2012, and 2014 for each county in Prince Edward Island.
** 500 beetles and over can result in crop failure.
Survey of Click beetles across PEI
Potential to impact agriculture • Once infected, agricultural land will remain
infected until adequate control measures to eliminate the larvae are implemented.
• If wireworms are not controlled, the land may become a important source of adult beetle that will infest other fields.
• Because of the wide host range, good agricultural land may become unsuitable for crop production.
• 5 year life cycle. • Soil dwelling. • Difficult to monitor because of aggregated field
distribution. • Several generations in the same field. • Damage occurs in the spring and fall. • Feed on a wide variety of crop species – oats, wheat,
barley, clover, corn, carrots, lettuce, onions, peas, potatoes, parsnips cabbage, beans, rutabagas etc.
Grain crops • Grain crops provide a good food source for
wireworms • Growing grain for several years in a row
can influence the buildup of wireworm population
• Under-seeding results in abundance of food which is beneficial to wireworm survival
18
Wireworm research at AAFC Charlottetown: Crop Rotation Study To Reduce Wireworm Damage (funded by
Pest Management Centre, 2007-2010) Brown Mustard, Buckwheat, Barley /Clover
Crop Rotation
Crops
Total Market yield (t/
ha)
Tubers with no Damage
(t/ha)
Average Number of Holes per tuber
Tonnes/ha lost due to
damage (for Processing)
(t/ha)
Tonnes/ha Marketable
(for Processing)
(t/ha) Brown Mustard 45.6 a1 16.2 a 04 a 0.5 a 45.1 a
Buckwheat 45.9 a 12.6 a 06 a 2.6 a 43.3 a
Barley 47.3 a 2.3 b 20 b 16.8 b 30.5 b
Table 1. Total market yield, number of undamaged tubers, holes per tuber, tonnes per hectare lost due to wireworm damage and marketable yield for the processing market in a potato crop following a 2 year rotation with brown mustard, buckwheat, barley/clover or alfalfa at Hazelbrook in Prince Edward Island, Canada.
Why does Brown Mustard work? • Because the plant tissue has
Allyl-glucosinolate (GTC) • When plant material starts to
breakdown and enzyme Myronase reacts with the tissue to produce Isothiocynates (ITC)
Glucosinolate
Enzyme Myronase
+ Isothiosynate ITC
Why does Brown Mustard work?
• The plant tissue has Allyl-glucosinolate (GTC)
• 2-phenylethyl in its roots which is toxic to insects
• Brown Mustard (Brassicae juncea var. Centennial) 10lb/ac or 11.2kg/ha
• Buckwheat (var Mancan) 40lb.ac or 44.8kg/ha • 2 crops /year • Fertilizer 300lb/ac or 335kg/ha 17:17:17 banded at
planting in the spring • Plant early June
Crop Rotation
• Brown Mustard (var Centennial) 8-10lb/ac or 11.2kg/ha
• Buckwheat (var Mancan) 40lb.ac or 44.8kg/ha • 2 crops /year • Fertilizer 300lb/ac or 335kg/ha 17:17:17 banded at
planting in the spring • Plant early June • Disk the crop in late July before seeds mature
Crop Rotation
Crop Rotation
• After two-three weeks harrow the field to level it • Depending on the seeder you may need to roll it
before planting, mainly because you don’t want the mustard seed planted too deep
• Do not need to add fertilizer for the second planting
Crop Rotation • The 2nd crop should go in by the mid-late August • Wireworms come to the surface to feed by mid to
late September • You want the crop established and producing the
chemicals • This second crop does not need to be disked as it
will act as ground cover and will not produce seeds
X X
Can Metarhizium control wireworms by controlling click beetles? (in the years leading up to planting potatoes)
X
First of all, is Metarhizium even pathogenic to the adult beetles?
Tests in the lab say YES
Conidia spray
Conidia dust
Conidia granules
Number of days after treatment
% beetle mortality
Matador (λ – cyhalothrin) -spray positive control
Application of Metarhizium spores kills click beetles in the field
Click beetles recaptured 16 days post-‐treatment
Pheromone granules synergize the efficacy of Metarhizium when targe>ng A. obscurus click beetles using a banded applica>on
Mean number + s.e. of beetles per passive piMall trap (mean of 8 traps in each of 5 replicaPons =40 traps/data point)
Untreated
Dead
Metarhiziu
m
Almost all beetles killed
• Use Bait traps • Could be done in the spring or fall. • Depending on the size of the field at least 15
bait stations per acre
Assessing wireworm infestation in a field
Lightly pack soil back down (leave for 7 days) Place soil back in hole
Place approximately ¾ cup of cut up carrots in the hole around the flag
Place wire flag in the center of the hole
Set Bait probe on top of the ground and step on it creating a nice circular hole 3 ½ inches across and 5 ½ inches deep
Placing Bait Traps
Place wire flag in the center of bait probe and push the probe into the ground
Pull bait probe from the ground
Place bait probe into a 12lb bag and remove sample
Check to see if any carrots remain in the hole and if some remain collect them as well
Label bag with appropriate tag and tie and store at 4C until time to sort for wireworms
Collecting Bait Traps
• Count the number of wireworms and calculate number per bait
• Threshold 1-2 wireworms per bait • Finding no wireworms does not necessarily
mean that none are present in the field. The higher the number of bait stations the better the accuracy
Assessing wireworm infestation in a field
Baiting your field Baits should be placed randomly across the field to compensate for this aggregated distribution of wireworms
STRATEGIES TO REDUCE DAMAGE 1. Find out if you have wireworms in your field and
assess populations. 2. If you work up a long term sod field do not plant a
valuable crop. 3. Plant brown mustard (Brassice juncea var centennial)
or buckwheat (var Mancan) as a rotation crop as shown above.
4. Try not to plant a preferred host such as grain every year.
5. For root crops harvest early before wireworms come up to the surface to feed in the fall.
Contact information [email protected] - Phone 902-370-1374