Post on 07-Mar-2020
Renovation of raspberry fields Tom Forge, Elizabeth Kenney, Bernie Zebarth, Denise Neilsen
Pacific Agri-Food Research CentreAgassiz, BC V0M 1A0Tom.Forge@agr.gc.ca
Abbotsford aquifer workshopAbbotsford, May 2, 2012
Renovation of raspberry fields
• Stand vigour and berry yields begin declining after 4 to 7 years
– Soil-borne pathogens• Root lesion nematodes• Phytophthora rubi
– Viruses (RBDV)– Soil chemical properties, e.g. pH
• The process:– Deep tillage– Fumigated (fall)– Manure often applied (spring)
Root-lesion nematode: Pratylenchus penetrans
•Pathogen of all fruit crops in region•Widespread (~75% of RB fields)•Persistent, chronic stresses•Infested plants more prone to other stresses – disease complexes
Photo: Oregon State Univ.
Raspberry decline and replant disorders are part of a broader problem: Declining soil health and productivity
• Declining soil organic matter and soil biological activity– Lower mineralization of
nutrients– Reduced CEC and buffering– Reduced WHC– Compaction/reduced structure
(biogenic)– Loss of soil biodiversity– Increased prevalence of soil-
borne plant pathogens
Monoculture x Clean tillage x 30 yrs = degraded soil…
Sustainable alternatives to fumigation are needed
• Emerging restrictions on fumigation– Buffer zones
• Detrimental to soil health– Short term benefits vs long-term decline
• Pathogen suppressive cover crops?• Organic amendments ?
• manures and composts
...that minimize impacts of root pathogens and enhance soil health
The challenge:To use manure-based amendments to manage root diseases/enhance soil health … without increasing nitrate leaching
• ~330,000 tons poultry manure produced in FV in 2010• Regional recycling imperative• Is composted manure an option?• Need to clarify distinctions between compost and manure
Compost –vs- manure: properties
Reduced risk of fecal contamination
C/N 15 to 25
minimal NH4-N & organic acids
humic acids & thermophilic microflora
little labile C – less rapid stimulation of soil microbial biomass (immobilization)
more stable N release
greater potential to increase soil C per unit PAN
0
10
20
30
40
50
60
g N
per
kg
mat
eria
l
PMC BM LM
Organic Ammonium Nitrate
Compost –vs- manure: disease suppression
Compost• Suppression demonstrated for many
fungal pathogens• Mode of action: enhancement of
antagonistic rhizosphere microbes; SIR• Previous research limited to incorporation
into potting media or seed beds• Suppression of parasitic nematodes
under field conditions?
Manure• Suppression demonstrated for some
fungal pathogens and nematodes• Mode of action: biofumigation
• Ammonia, VFA's, etc.• Large doses required• Previous research limited to annual
crops; longer-term influences on soil health and suppression not considered
Renovation experimentsHow do fumigation, fall cover crop, manure and
compost compare with respect to?1. Pathogen suppression2. Crop establishment3. Potential for N leaching
Treatments:1. Control2. Fumigation (Dazomet)3. Fall barley cover crop4. “Low” spring manure (100 kg PAN/ha)5. “High” spring manure6. “High” spring compost
fall winter
Renovation experiment 1: setup - spring 2010
“1-inch” application~57 Mg/ha manure (2700 kg N/ha)~88 Mg/ha compost (1650 kg N/ha)
Pratylenchus population dynamics
org. amends applied
planted
Cane counts & cane diameters 2011 (end of second growing season)
a
b
abb
cc
Soil Physical Properties
Raspberry Renovation July 2010
0.90
0.95
1.00
1.05
1.10
1.15
1.20
TreatmentsBu
lk D
ensi
ty g
m/c
c t1 controlt2 fumigatet3 covert4 low manuret5 high manuret6 compost
See Kenney poster for more on physical properties…
Soil chemical properties
See E. Kenney poster for more…
c
b
a
b
a
cAmends
applied
planted
Similar quantities of material, different implications for nitrate leaching
What have we learned?If composted, manure can be used in the raspberry production system to improve soil conditions and crop health:•Reduce pathogen populations
•Improve soil physical and chemical properties
•Improve early raspberry growth
With reduced risk of nitrate leaching
With reduced risk of fecal bacterial contamination
Next steps…Other composts
Lower rates
Application to beds
Economics of composting/utilization
Thanks!
Chaim KemplerBrian HardingMark SweeneyTom WaltersCarol KochShaobing YuNaomi HashimotoNathalie ArmstrongBen FreyDru YatesMelissa Iverson
AAFC-SAGESAAFC-GAPSRaspberry Industry Development CouncilWashington Red Raspberry Commission
Effect of low crop vigourPre-leaching 2010
org. amends
planted
Soil nitrate:Second fall/winter
020406080
100120140160
kg N
O3-
N/h
a
Oct. 1, 2010 Nov. 7, 2010
Nitrate-N (kg N/ha)
ControlFumigateCover cropManLowManHighCompostb
a
a
----c--------b-------------
Similar quantities of material, different implications for nitrate leaching
Primocane biomass & P. penetrans, 2010
a
bb
bc
cc
Renovation experiment 2 (2010)
•7 treatments x 5 reps•fumigate+compost treatment•Canes removed & plowed Aug. 30•Rototilled & barley planted September 21•Fumigated Oct. 1, 65 g/m2•Soil sampled Oct. 1 (before fumigating)
Renovation experiment 2:P. penetrans population densities - 2011
a
b
yb
b
yc
c cx x
y
y
z
Mt. Vernon study
Clearbrook studies
Surface application of manure and compost to established crops
Can we measure benefits if surface applied at modest (N-based) ratessoil health indicators and nutrient availability
Surface application at N-based rates…
• Modest improvements in growth/yield but no clear differentiation between manure and compost
• Biodiversity & organic matter accumulation– Compost > manure > fertilizer– Mixed results re. Pratylenchus penetrans
• Variation in root biomass related to P. penetrans population densities• CDMS may reduce soil NO3-N without affecting crop N
– reduced risk of leaching• Enhanced soil food web/nutrient turnover compensates for smaller pools
of mineral N?• Need longer-term experiments
– consider P loading – effects on N use efficiency