2/12/2014
1
The New Zealand Institute for Plant & Food Research Limited
Postharvest diseases of avocados-
from orchard to market
Cultural and Chemical control
Dr Kerry Everett
Mt Albert Research Centre
Auckland, New Zealand
The New Zealand Institute for Plant & Food Research Limited
www.avocadosource.com
2/12/2014
2
The New Zealand Institute for Plant & Food Research Limited
Climate Comparison
– Uruapan Mexico and Tauranga New Zealand
Data redrawn from www.worldclimateguide.co.uk
http://geo-mexico.com/?p=2302
The New Zealand Institute for Plant & Food Research Limited
Climate Comparison
–La Serena Chile and Tauranga New Zealand
Data redrawn from www.worldclimateguide.co.uk
Irazabal, F.G. 2001. History and
Development of the Avocado in
Chile. California Avocado Society
Yearbook 85: 113-128
2/12/2014
3
The New Zealand Institute for Plant & Food Research Limited
Climate Comparison
–Lima Peru and Tauranga New Zealand
Data redrawn from www.worldclimateguide.co.uk
The New Zealand Institute for Plant & Food Research Limited
www.avocadosource.com
Irazabal, F.G. 2001. History and
Development of the Avocado in Chile.
California Avocado Society Yearbook
85: 113-128
J F M A M J J A S O N D
Mexico
California
Australia
Chile
New Zealand
Peru
South Africa
2/12/2014
4
The New Zealand Institute for Plant & Food Research Limited
Comparison of exports by value (USD)
www.factfish.com
2012 data
The New Zealand Institute for Plant & Food Research Limited
New Zealand avocado exports
Source: NZ Avocado Growers Association Inc. & Avocado Industry Council Ltd. Annual Report 2014
2/12/2014
5
The New Zealand Institute for Plant & Food Research Limited
Two postharvest diseases
Stem-end rots
(pudrición peduncular)
Body rots (antracnosis)
The New Zealand Institute for Plant & Food Research Limited
2/12/2014
6
The New Zealand Institute for Plant & Food Research Limited
The New Zealand Institute for Plant & Food Research Limited
What causes rots?
0
2
4
6
8
10
12
14
16
18
20
C.a. C.g. B.p. B.d. P.
Me
an
no
. is
ola
tio
ns/1
00
fru
it
Fungus
body rots
stem-end rots
Colletotrichum acutatum
Colletotrichum gloeosporioides
Botryosphaeria parva
Botryosphaeria dothidea
Phomopsis sp.
2/12/2014
7
The New Zealand Institute for Plant & Food Research Limited
Are rots a problem?
• USA
• Three strikes and you are out (late ’90’s)
• Rots
• Measles = rots in green fruit
• Australia
• 50% of consumers do not repeat purchase because of poor quality
due to rots (1990’s)*
• Large backlog of NZ fruit in the market place leading to extended
storage and fruit age problems (1997)
• Three issues
• rots
• fruit age
• measles
*Ledger, S., Campbell, T., Banks, A., Atkinson,I, Kernot, I. and Fullelove, G. 1993
Internal quality of avocados in retail shops.
Queensland Department of Primary Industries Internal Report (Avoman). 23pp.
The New Zealand Institute for Plant & Food Research Limited
What did we do to fix it?
Research
Avocado Rot Survey
• Three year survey of orchards to identify cultural and grower
practices that affected rots
• Followed it up with replicated trials
Determined:
• the storage limits of fruit
• the criteria for infection
• the relationship between lenticel damage and measles
Logistics
• Reviewed the research that had already been conducted in NZ
• Tightened up timeframes in the logistics pathway
• Cooperation amongst exporters to rationalise flow of avocados
to the market
2/12/2014
8
The New Zealand Institute for Plant & Food Research Limited
Avocado Rot Survey
• Sampled 8 orchards in January each year for 3 years
• Sampled an additional 13 orchards for 2 of the 3 years
• Assessed 100 fruit from each orchard for rots
• Collected orchard parameters including spray diaries and weather
• Analysed the data
Everett KR, Boyd LM, Pak HA, Cutting JGM 2007.
Calcium, fungicide sprays and canopy density influence
postharvest rots of avocado. Australasian Plant Pathology
36(1): 22-31.
The New Zealand Institute for Plant & Food Research Limited
Fungicide sprays reduce rots
0 2 4 6 8 10 12
0
5
10
15
20
25
30
35
40
45
50R
2=83%
P=0.002
Y = 44.0 - 2.4 X
Me
an
no
. o
f fr
uit
wit
h s
tem
-en
d r
ots
(%
)
Mean no. of fungicide applications
0 2 4 6 8 10 12
0
5
10
15
20
25
30
R2=74%
P=0.04
Y = 16.0 + 3.4 X - 0.4 X2
Me
an
no
. o
f fr
uit
wit
h b
od
y r
ots
(%
)
Mean no. of fungicide applications
2/12/2014
9
The New Zealand Institute for Plant & Food Research Limited
Nutrition affects body rots
0.045 0.050 0.055 0.060 0.065 0.070 0.075 0.080 0.085 0.090 0.095 0.100
0
5
10
15
20
25
30
35
40
45
50
0
5
10
15
20
25
30
35
40
45
50
2000
no
. o
f fr
uit w
ith
bo
dy r
ots
(%
)
Ca+Mg
K
Y= 396.5 exp(-X/0.02) - 0.51
R2 = 56%
2001
The New Zealand Institute for Plant & Food Research Limited
Rainfall inversely related to body rots
0 20 40 60 80 100 120
0.00
0.05
0.10
0.15
0.20
0.25
0.30
0.35
P=0.03
R2=57.4%
Y=0.25-0.002X
Bo
dy r
ots
(m
ean
sev
eri
ty)
mm rainfall 20 days before picking
2/12/2014
10
The New Zealand Institute for Plant & Food Research Limited
Fig. 5. Relationships between body rots and calcium (Ca), magnesium (Mg) and
potassium (K) expressed as (Ca+Mg)/K, rainfall and temperature.
Lo
g1
0 (n
o. o
f fr
uit
wit
h
bo
dy
ro
ts )
C
a+M
g
K
Rai
nfa
ll (
mm
)
Ca+Mg
K
Rainfall (mm) Temperature (°C)
0.050 0.055 0.060 0.065 0.070 0.075 0.080
0.8
1.0
1.2
1.4
1.6
1.8
P=0.02
R2=70.4%
Y=2.5-21.6X
60 80 100 120 140 160 180 200
0.8
1.0
1.2
1.4
1.6
1.8
P=0.03
R2=63.3%
Y=1.78-0.006X
16.2 16.4 16.6 16.8 17.0 17.2 17.4
0.050
0.055
0.060
0.065
0.070
0.075
0.080
P=0.024
R2=67.2%
Y=0.399-0.03X
60 80 100 120 140 160 180 200
0.050
0.055
0.060
0.065
0.070
0.075
0.080
P=0.03
R2=66.2%
Y=0.04+0.0002X
16.2 16.4 16.6 16.8 17.0 17.2 17.4
0.8
1.0
1.2
1.4
1.6
1.8 P=0.01
R2=75.6%
Y=14.1-0.77X
16.2 16.4 16.6 16.8 17.0 17.2 17.4
60
80
100
120
140
160
180
200
Rainfall inversely related to body rots
30 days BH 40 days BH
The New Zealand Institute for Plant & Food Research Limited
Fig. 5. Relationships between body rots and calcium (Ca), magnesium (Mg) and
potassium (K) expressed as (Ca+Mg)/K, rainfall and temperature.
Lo
g1
0 (n
o. o
f fr
uit
wit
h
bo
dy
ro
ts )
C
a+M
g
K
Rai
nfa
ll (
mm
)
Ca+Mg
K
Rainfall (mm) Temperature (°C)
0.050 0.055 0.060 0.065 0.070 0.075 0.080
0.8
1.0
1.2
1.4
1.6
1.8
P=0.02
R2=70.4%
Y=2.5-21.6X
60 80 100 120 140 160 180 200
0.8
1.0
1.2
1.4
1.6
1.8
P=0.03
R2=63.3%
Y=1.78-0.006X
16.2 16.4 16.6 16.8 17.0 17.2 17.4
0.050
0.055
0.060
0.065
0.070
0.075
0.080
P=0.024
R2=67.2%
Y=0.399-0.03X
60 80 100 120 140 160 180 200
0.050
0.055
0.060
0.065
0.070
0.075
0.080
P=0.03
R2=66.2%
Y=0.04+0.0002X
16.2 16.4 16.6 16.8 17.0 17.2 17.4
0.8
1.0
1.2
1.4
1.6
1.8 P=0.01
R2=75.6%
Y=14.1-0.77X
16.2 16.4 16.6 16.8 17.0 17.2 17.4
60
80
100
120
140
160
180
200
Rainfall inversely related to body rots
30 days BH 40 days BH
2/12/2014
11
The New Zealand Institute for Plant & Food Research Limited
Canopy index influences body rots dead branches + (canopy density x leaf height inside canopy)/tree spacing
0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0
0.00
0.05
0.10
0.15
0.20
0.25
0.30
0.35
0.40
0.45 P=0.02
R2=23.3%
Y=0.03+0.12X
mean s
everi
ty (
body r
ots
)
canopy index
The New Zealand Institute for Plant & Food Research Limited
3 way analysis of variance (body rots)
Fitted : logten.ca.mg.k. + no..of.months.sprayed + canopy.index
bo
dy.r
ots
0.05 0.10 0.15 0.20 0.25 0.30
0.1
0.2
0.3
0.4
R2=67.4%
P=0.000125
2/12/2014
12
The New Zealand Institute for Plant & Food Research Limited
Replicated trials
1. Nutrition, canopy management and irrigation
2. Fungicide spray trial
3. Fruit age
4. Lenticel damage vs. Measles
The New Zealand Institute for Plant & Food Research Limited
Nutrition, canopy management and root
health (root health = irrigation + Phytophthora control)
R + R + R - R - R + R + R - R -
x x x x x x x x
xN+ x xN+ x xN+ x xN+ x
xN- x xN- x xN- x xN- x
x x x x x x x x
x xN- x xN- x xN- x xN-
x xN+ x xN+ x xN+ x xN+
x x x x x x x x
Key
symbol explanation
x Tree
Assessed trees
C-
R Root health
C Canopy management
N Nutrition
Two orchards- organic and conventional
C- = no canopy management
•Dead branches removed from the canopy of all other trees,
•the lower branches were trimmed to a height of 1 m.
2/12/2014
13
The New Zealand Institute for Plant & Food Research Limited
The New Zealand Institute for Plant & Food Research Limited
Nutrition, canopy management and
irrigation
R + R + R - R - R + R + R - R -
x x x x x x x x
xN+ x xN+ x xN+ x xN+ x
xN- x xN- x xN- x xN- x
x x x x x x x x
x xN- x xN- x xN- x xN-
x xN+ x xN+ x xN+ x xN+
x x x x x x x x
Key
symbol explanation
x Tree
Assessed trees
C-
R Root health
C Canopy management
N Nutrition
Two orchards- organic (5-6 yo) and conventional (15-20 yo)
C- = no canopy management
•Dead branches removed from the canopy of all other trees,
•the lower branches were trimmed to a height of 1 m.
R+ = Root health
• irrigated
• treated with phosphorous acid or mulch (organic orchard)
N+ = Nutrition
•Calcium was applied to the ground under trees.
2/12/2014
14
The New Zealand Institute for Plant & Food Research Limited
Results
Factors Body rots Stem-end rots Total rots
Tree n.s. n.s. n.s.
Box n.s. n.s. n.s.
N 0.004 n.s. 0.002
R <0.0001 <0.0001 <0.0001
C n.s. n.s. n.s.
Factors Body rots Stem-end rots Total rots
Tree n.s. n.s. n.s.
Box 0.05 n.s. n.s.
N 0.05 n.s. n.s.
R n.s. n.s. n.s.
C n.s. n.s. 0.03
Conventional orchard (trees 15-20 years old)
Organic orchard (trees 5-6 years old)
The New Zealand Institute for Plant & Food Research Limited
Fungicide spray trial
Aims:
• More efficaceous fungicides
• Regional differences?
Procedures
• In vitro screening
• Replicated spray trials
2/12/2014
15
The New Zealand Institute for Plant & Food Research Limited
In vitro testing
Fungicide
C. acutatum
C. gloeosporioides
B. parva
B. dothidea
Phomopsis sp.
boscalid <0.1 <0.1 18.2 27.7 74.8
boscalid/
pyraclostrobin
7.0 0.2 2.3 0.2 0.2
Kocide 2000DS 0.4 8.1 0.6 15.6 1.5
Kocide 3000 7.3 140.9 0.3 4.8 0.1
Champ DP 1.0 57.6 0.1 11.4 2.7
copper
hydroxosulphate
0.1 2.3 4.0 98.2 1.5
dithianon <0.1 <0.1 3.1 18.5 <0.1
fluazinam 0.1 1.9 0.1 0.1 0.1
EC 50 spore germination
Everett KR, Timudo-Torrevilla OE 2007. In vitro fungicide testing for
control of avocado fruit rots. New Zealand Plant Protection 60: 99-103
http://www.nzpps.org/.
Everett KR, Owen SG, Cutting JGM 2005. Testing efficacy of fungicides
against postharvest pathogens of avocado (Persea americana cv. Hass).
NZ Plant Protection 58: 89-95. http://www.nzpps.org/
The New Zealand Institute for Plant & Food Research Limited
Fungicide
C. acutatum
C. gloeosporioides
B. parva
B. dothidea
Phomopsis sp.
boscalid 1921.0 >* 837.7 2154.4 >
boscalid/
pyraclostrobin
0.2 0.1 0.2 0.0 0.8
Kocide 2000DS 2540.7 647.3 304.7 153.2 105.8
Kocide 3000 867.2 297.1 228.1 118.1 101.8
Champ DP 346.7 257.2 1321.7 197.0 193.3
copper hydroxosulphate 910.5 402.1 1645.3 749.9 543.0
dithianon 44.2 201.4 989.6 540.3 17.2
fluazinam 7.8 1.7 6.6 4.3 0.5
*EC50 value is greater than the highest concentration used
In vitro testing
EC 50
mycelial growth
Everett KR, Timudo-Torrevilla OE 2007. In vitro fungicide testing for
control of avocado fruit rots. New Zealand Plant Protection 60: 99-103.
http://www.nzpps.org/
Everett KR, Owen SG, Cutting JGM 2005. Testing efficacy of fungicides
against postharvest pathogens of avocado (Persea americana cv. Hass).
NZ Plant Protection 58: 89-95. http://www.nzpps.org/
2/12/2014
16
The New Zealand Institute for Plant & Food Research Limited
Field trials
fluazanim
dithia
non
boscalid
/pyra
clo
str
obin
boscalid
Bio
sta
rt
Cham
p D
P
Kocid
e 3
000
untr
eate
d --
0
10
20
30
40
50
60
70
***
*
Body rotsm
ea
n s
eve
rity
(0
-10
0 s
cale
)
Treatment
fluazanim
dithia
non
boscalid
/pyra
clo
str
obin
boscalid
Bio
sta
rt
Ch
am
p D
P
Kocid
e 3
000
untr
eate
d --
0
2
4
6
8
10
Stem-end rots
me
an
seve
rity
(0
-10
0 s
cale
)
Treatment
Everett, K.R., Timudo-Torrevilla, O.E., Hill, G.N. and Dawson, T.E. 2009.
Field testing alternatives to copper for controlling avocado fruit rots. NZ
Plant Protection 61: 65-69. http://www.nzpps.org/
The New Zealand Institute for Plant & Food Research Limited
Regional Field Trials
Fungicide product1 Active ingredient Chemical group
Rate applied Product/100 L
Pristine pyraclostrobin/ boscalid
strobilurin/ carboxamide
60 g
Kocide Opti copper hydroxide copper 90 g
Shirlan fluazinam pyridinamine 100 mL
4 orchards per region
4 treatments
100 fruit per treatment
8 applications (March to October)
Harvested November
2/12/2014
17
The New Zealand Institute for Plant & Food Research Limited
ANOVA Factors SER BR
Treatment <0.0001 <0.0001
Replicate n.s. n.s.
Region <0.0001 <0.0001
Orchard <0.0001 <0.0001
Fungicide product1 Active ingredient Chemical group
Rate applied Product/100 L
Pristine pyraclostrobin/ boscalid
strobilurin/ carboxamide
60 g
Kocide Opti copper hydroxide copper 90 g
Shirlan fluazinam pyridinamine 100 mL
4 orchards per region
4 treatments
100 fruit per treatment
8 applications (March to October)
Harvested November
The New Zealand Institute for Plant & Food Research Limited
Regional Field Trials
Pyraclostrobin/boscalid Fluazinam Copper hydroxide Untreated
0
10
20
30
40
50
60
c b b a
Ro
t In
cid
en
ce
(%
)
Treatment
SER
BR
a b b b
Everett, K.R., Pushparajah, I.P.S., Taylor, J.T., Astill, M.S., King, D.B.
and Ah Chee, A. 2010. Fungicide spray trial in three avocado growing
regions in New Zealand. NZ Avocado Growers' Association Annual
Research Report Vol. 8: 99-110. available on-line at
www.avocadosource.com
2/12/2014
18
The New Zealand Institute for Plant & Food Research Limited
Storage limits of fruit
• Fruit inoculated with Colletotrichum acutatum
• Then placed in coolstore (5.5oC)
• Week 0 fruit was held at 20oC and assessed for SER after 1,3, 4, 6 and 7 days
• After 2 weeks fruit was removed from the coolstore, then every week for 7 weeks
• The fruit was assessed for SER and firmness on 5 occasions as for day 0:
usually 1,3, 4, 6 and 7 days after removal from the coolstore
0 2 3 4 5 6 7 Weeks in coostorage (5.5oC) 5.5oC
20oC
= 20 inoculated fruit &
20 uninoculated fruit
The New Zealand Institute for Plant & Food Research Limited
Storage limits of fruit
0 7 14 21 28 35 42 49
0
10
20
30
40
50
60
70
80
90
100
Ripeness of 5 by hand inoculated
control
ste
m e
nd
ro
t in
cid
en
ce (
%)
time in coolstorage (days)
0 7 14 21 28 35 42 49
0
10
20
30
40
50
60
70
80
90
100
inoculated
control
ste
m e
nd
ro
t i
ncid
en
ce (
%)
time in coolstorage (days)
Fruit assessed when ripe
Everett, K.R. & Pak, H.A. 2002
Patterns of stem-end rot development
in coolstorage.
NZ Avocado Growers’ Association
Annual Research Report 2: 68-74
Dixon, J., Pak, H.A., Mandemaker, A.J.,
Smith, D.B., Elmsly, T.A. & Cutting, J.G.M. 2003
Fruit age management: the key to successful long
distance export of New Zealand avocados.
NZ Avocado Growers’ Association
Annual Research Report 3: 60-65
Fruit assessed when hard
2/12/2014
19
The New Zealand Institute for Plant & Food Research Limited
Infection criteria
10 12 14 16 18 20 22 24 26 28 30
0
10
20
30
40
50
60
70
80
90
100
C. gloeosporioides 24 hours
Y = 6.75 x (T-20)0.958
x (28.25-T)0.441
T optimum=25.6oC
R2=94.3%
P=0.006
% s
po
re g
erm
inati
on
Temperature (oC)
10 12 14 16 18 20 22 24 26 28 30
0
10
20
30
40
50
60
70
80
90
100
C. acutatum 24hr
Y=3.76 x (T-Tmin
)1.04
x (Tmax
-T)0.73
T optimum=23.3oC
R2=86%
P=0.003
% s
po
re g
erm
inati
on
Temperature (oC)
10 12 14 16 18 20 22 24 26 28 30
0
10
20
30
40
50
60
70
80
90
100
B. parva 24hr
% s
po
re g
erm
inati
on
Temperature (oC)
10 12 14 16 18 20 22 24 26 28 30
0
10
20
30
40
50
60
70
80
90
100
Y = 60
1+e-1(x-17)
R2=46.2%
P=0.06
Phomopsis 24hr
% s
po
re g
erm
inati
on
Temperature (oC)
Everett, K.R. & Pak, H.A. 2002
Infection criteria for pathogens
causing body rots in avocados
NZ Avocado Growers’ Association
Annual Research Report 2: 54-58
The New Zealand Institute for Plant & Food Research Limited
Jan
uary
Fe
bru
ary
Ma
rch
Ap
ril
Ma
y
Ju
ne
Ju
ly
Au
gu
st
Sep
tem
ber
Oc
tob
er
No
ve
mb
er
De
ce
mb
er
Jan
uary
8
9
10
11
12
13
14
15
16
17
18
19
20
21
Phomopsis sp.
C. acutatum
C. gloeosporioides
Kaitaia
Whangarei
TePuke
Tem
pe
ratu
re (
oC
)
10 12 14 16 18 20 22 24 26 28 30
0
10
20
30
40
50
60
70
80
90
100
B. parva 24hr
% s
po
re g
erm
inati
on
Temperature (oC)
Everett & Pak 2002
NZ Avocado Growers’ Association
Annual Research Report 2: 68-74. www.avocadosource.com
2/12/2014
20
The New Zealand Institute for Plant & Food Research Limited
What causes measles?
The New Zealand Institute for Plant & Food Research Limited
2/12/2014
21
The New Zealand Institute for Plant & Food Research Limited
The New Zealand Institute for Plant & Food Research Limited
-1.5
-1.0
-0.5
0.0
0.5
1.0
1.5
2.0
2.5
unbagged bagged separate
flask
fruit
wate
r lo
ss (
g)
2/12/2014
22
The New Zealand Institute for Plant & Food Research Limited
Simulate damage
“Jostle” 10 x
The New Zealand Institute for Plant & Food Research Limited
2/12/2014
23
The New Zealand Institute for Plant & Food Research Limited
0.1 mm
The New Zealand Institute for Plant & Food Research Limited
0.1 mm
2/12/2014
24
The New Zealand Institute for Plant & Food Research Limited
0.1 mm
The New Zealand Institute for Plant & Food Research Limited
Fungal isolations from ‘measles’
C.a. C.g. B.p. B.d. P. No
isolation Sap.
control 6 24 2 0 0 163 5
‘measles’ 50 20 4 0 29 85 12
C.a. Colletotrichum acutatum
C.g. Colletotrichum gloeosporioides
B.p. Botryosphaeria parva
B.d. Botryosphaeria dothidea
P. Phomopsis sp.
Sap. saprotrophs
2/12/2014
25
The New Zealand Institute for Plant & Food Research Limited
Lenticel damage Measles
not
imbibed
imbibed not
imbibed
imbibed
Treatmentsa not jostled 2.9±0.57 1.5±0.31 5.2±2.02 5.5±1.63
jostled 7.1±1.02 10.5±1.18 16.9±4.31 17.2±3.58
P valuesb imbibed(I) 0.047
<0.0001
0.010
ns
ns
0.016
ns
ns
jostled(J)
I x J
fruit
aValues are means ± S.E.M. for 40 fruit
bP values are from a three-way analysis of variance
The New Zealand Institute for Plant & Food Research Limited
Conclusions
• Fruit are more susceptible to lenticel damage when imbibed and
when damaged
• Fruit are more susceptible to ‘measles’ when damaged, but
imbibation had no effect
• Measles are probably due to fungal infection, but lenticel damage
is a physical disorder
• To reduce lenticel damage (in NZ), pick before rainy periods
• To reduce measles, apply fungicides
• For both, make sure fruit are treated as gently as possible after
harvest
.
Everett KR, Hallett IC, Rees-George J, Chynoweth RW, Pak HA. 2008.
Avocado lenticel damage: the cause and the effect on fruit quality.
Postharvest Biology and Technology 48: 383-390
2/12/2014
26
The New Zealand Institute for Plant & Food Research Limited
Literature review - Postharvest fungicides
Treatment No. of trials % efficacy
Flusilazole 1 68.8
Permanganate (acidified) 1 58
Prochloraz 10 55.3
Benomyl 7 52.7
Hypochlorite 5 36.6
Benzalkonium chloride 1 18.8
Thiabendazole 2 17.8
10% ethanol 2 13
Phosphorous acid 2 4.8
Carbendazim 2 2.5
Kresoxim-methyl 2 8
Boscalid/pyraclostrobin 1 0
Everett, K.R. 2002 Avocado fruit rots: A review of industry funded
research. NZ Avocado Growers’ Association Annual Research Report 2:
8-16. www.avocadosource.com
The New Zealand Institute for Plant & Food Research Limited
Literature review - Postharvest fungicides
Prochloraz treatment- apply as soon after harvest as possible
Hours after harvest fruit treated
Not treated 0 2 4 12 24
% rots 73 28 27 35 34 40
y = 3,1x + 23,5 R² = 0,8371
0
10
20
30
40
50
0 2 4 12 24
% r
ots
Hours after harvest fruit treated
Everett, K.R. 2002 Avocado fruit rots: A review of industry funded research.
NZ Avocado Growers’ Association Annual Research Report 2: 8-16 www.avocadosource.com
2/12/2014
27
The New Zealand Institute for Plant & Food Research Limited
Finally- to reduce postharvest issues
Apply fungicides
Irrigate the trees and control Phytophthora
Apply calcium
Apply postharvest fungicides immediately after harvest
Minimise handling damage
Get fruit to the marketplace as quickly as possible
Rationalise the flow of fruit to the marketplace so there are no gluts leading
to fruit age problems
The New Zealand Institute for Plant & Food Research Limited
The New Zealand Institute for Plant & Food Research Limited
Gracias muchas Ian Hallett, Henry Pak, Shamini Pushparajah,
Olimpia Timudo, Jonathan Rees-George
The Organising Committee
Bruno Defilippi
Raúl Ferreyra
Sebastián Rivera
Fondecyt
WageningenUR Chile