View
6
Download
0
Category
Preview:
Citation preview
agric
ultu
re,
fore
stry
& fi
sher
ies
Dep
artm
ent:
Agr
icul
ture
, For
estry
and
Fis
herie
sR
EPU
BLI
C O
F SO
UTH
AFR
ICA
Econ
omic
impl
icat
ions
C
itru
s g
ree
nin
g r
ed
uce
s th
e q
ua
ntit
y a
nd
qu
alit
y o
f ci
trus
fru
it an
d ev
entu
ally
the
infe
cted
tre
es b
ecom
e un
prod
uctiv
e. A
n in
fect
ed t
ree
prod
uces
fru
it th
at is
un
suita
ble
for
sale
as
fres
h fr
uit o
r fo
r ju
ice
mak
ing.
It is
a q
uara
ntin
e pe
st in
the
coun
trie
s w
here
it is
not
ye
t pre
sent
. The
spr
ead
of th
is d
isea
se w
ithin
a p
revi
-ou
sly
pest
-fre
e co
untr
y ca
n ha
mpe
r th
e op
port
unity
of
that
cou
ntry
to a
cces
s po
tent
ial c
itrus
mar
kets
whi
ch
may
impo
rt o
nly
from
citr
us g
reen
ing
pest
-fre
e ar
eas.
C
itrus
gre
enin
g, t
here
fore
, ne
gativ
ely
affe
cts
acce
ss
to m
ajo
r in
tern
ati
on
al
citr
us
ma
rke
ts,
such
as
the
Uni
ted
Sta
tes
of A
mer
ica
and
the
Eur
opea
n U
nion
.
Legi
slat
ive
impl
icat
ions
In
ter
ms
of t
he A
gric
ultu
ral P
ests
Act
, 19
83 (
Act
No.
36
of
1983
), C
ontr
ol M
easu
res
R.1
10 o
f 27
Jan
uary
19
84 (
as a
men
ded)
, mov
emen
t of c
itrus
pro
paga
tion
mat
eria
l fro
m o
ne a
rea
to a
noth
er w
ithin
the
Rep
ublic
of
Sou
th A
fric
a is
pro
hibi
ted
unle
ss t
he m
ovem
ent
is
au
tho
rise
d b
y m
ea
ns
of
a p
erm
it o
r th
e m
ate
ria
l is
cert
ified
as
pest
free
. The
Dep
artm
ent o
f Agr
icul
ture
, F
ore
stry
an
d F
ish
eri
es
ren
de
rs in
spe
ctio
n s
erv
ice
s an
d is
sues
per
mits
to e
nsur
e co
mpl
ianc
e w
ith th
e ap
-pl
icab
le c
ontr
ol m
easu
res.
The
abo
vem
entio
ned
inte
rven
tions
will
ass
ist
in p
re-
vent
ing
the
furt
her
spre
ad o
f citr
us g
reen
ing.
Sour
ces
of in
form
atio
n
A
PH
IS F
acts
heet
, 200
7, C
itrus
Gre
enin
g: Q
uest
ions
and
Ans
wer
s,
Uni
ted
Sta
tes
Dep
artm
ent o
f Agr
icul
ture
.
J.V
. DA G
RA
CA 1
991,
Citr
us g
reen
ing
dise
ase,
Phy
topa
thol
ogy,
29:
10
9–13
6.
UN
IVE
RS
ITY O
F F
LO
RID
A,
20
05
, C
itru
s g
ree
nin
g—
An
oth
er
Th
rea
t to
A
gric
ultu
re, U
F-I
FA
S, U
SA
.
PIE
TE
RS
EN,
G.,
AR
RE
BO
LA,
E.,
BR
EY
TE
NB
AC
H,
J.H
.J.,
KO
RS
TE
N L
., L
E
RO
UX, H
.F.,
LA G
RA
NG
E H
., LO
PE
S, S
.A.,
ME
YE
R J
.B.,
PR
ET
OR
IUS M
.C.,
SC
HW
ER
DT
FE
GE
R, M
., V
AN V
UU
RE
N S
.P. &
YA
MA
MO
TO, P
. 201
0. A
sur
vey
for
“Can
dida
tus
Libe
ribac
ter”
spe
cies
in S
outh
Afr
ica
conf
irms
the
pre
sen
ce o
f o
nly
“C
a.
L.
afr
ica
nu
s” in
co
mm
erc
ial C
itru
s. P
lan
t D
isea
se,
94: 2
44–2
4.
Des
crip
tion
C
itrus
gre
enin
g, a
lso
know
n as
yel
low
dra
gon
dise
ase
or H
uang
long
bing
, is
one
of th
e m
ost s
erio
us b
acte
rial
dis
ea
ses
of
citr
us.
Th
ere
are
th
ree
kn
ow
n f
orm
s o
f ci
trus
gre
enin
g ca
usin
g ba
cter
ia,
nam
ely
the
Afr
i can
fo
rm (
‘Can
dida
tus
Libe
riba
cter
afr
ican
us’)
, th
e A
sian
fo
rm (
‘Ca
nd
ida
tus
Lib
eri
ba
cte
r a
sia
ticu
s’)
an
d t
he
Am
e ric
an fo
rm (
‘Can
dida
tus
Libe
ribac
ter a
mer
ican
us’).
The
Afr
ican
form
is h
eat s
ensi
tive
and
sym
ptom
s ar
e pr
oduc
ed u
nder
rel
ativ
ely
cool
con
ditio
ns (
20–2
4 °C
) w
hile
th
e A
sia
n f
orm
de
velo
ps
un
de
r b
oth
co
ol a
nd
war
m te
mpe
ratu
res
(up
to 3
2 °C
). L
ittle
is k
now
n ab
out
tem
pera
ture
req
uire
men
ts o
f the
Am
eric
an fo
rm.
Orig
in a
nd g
loba
l dis
trib
utio
nC
itru
s g
ree
nin
g p
rob
ab
ly o
rig
ina
ted
in C
hin
a in
th
e 19
00s.
20
13
Pub
lishe
d by
D
epar
tmen
t of A
gric
ultu
re, F
ores
try a
nd F
ishe
ries
P
rivat
e B
ag X
144
P
RE
TOR
IA
0001
Citr
us
gree
ning
– to
rep
ort o
ccur
renc
e or
sus
pect
ed o
ccur
renc
e of
the
dise
ase
–
Dire
ctor
ate:
Pla
nt H
ealth
Div
isio
n:
Ear
ly W
arni
ng S
yste
ms
Tel
:
01
2 31
9 63
84
Em
ail:
JanH
endr
ikV
@da
ff.go
v.za
– fo
r aw
aren
ess
and
prom
otio
n en
quiri
es –
Dire
ctor
ate:
Foo
d Im
port
and
Exp
ort S
tand
ards
Div
isio
n:
Pla
nt H
ealth
Pro
mot
ion
Tel
: 01
2 31
9 62
95
Em
ail:
Info
.sps
@da
ff.go
v.za
Nee
d m
ore
info
rmat
ion
?
‘Can
did
atu
s L
iber
ibac
ter
afri
can
us’
‘Can
did
atu
s L
iber
ibac
ter
asia
ticu
s’
‘Can
did
atu
s L
iber
ibac
ter
amer
ican
us’
teris
tic o
f gre
enin
g. O
ther
sym
ptom
s in
clud
e tw
ig d
ie-
back
, poo
r flo
wer
ing
and
stun
ted
grow
th.
Fru
it fr
om d
isea
sed
tree
s is
sm
all,
ofte
n ab
norm
al a
nd
typi
cally
som
e gr
een
colo
ur re
mai
ns e
ven
on ri
pe fr
uit.
Gre
en
ing
-aff
ect
ed
fru
it t
ast
e b
itte
r, m
ed
icin
al
an
d so
ur. S
eeds
usu
ally
abo
rt, a
nd fr
uit f
orm
atio
n is
poo
r.
Sym
p to
ms
vary
acc
ord
ing
to
th
e t
ime
of
infe
ctio
n,
stag
e of
dis
ease
, tre
e sp
ecie
s an
d tr
ee m
atur
ity.
Tran
smis
sion
T
his
dis
ea
se is
pri
ma
rily
sp
rea
d b
y tw
o s
pe
cie
s o
f ps
yllid
inse
ct, n
amel
y th
e A
sian
citr
us p
sylli
d (D
ia ph
o r-
ina
citr
i) an
d th
e A
fric
an c
itrus
psy
llid
(Trio
za e
rytr
eae)
. B
oth
sp
eci
es
tra
nsm
it th
e c
itru
s g
ree
nin
g p
ath
og
en
from
infe
cted
tre
es t
o he
alth
y tr
ees
as t
hey
feed
on
the
plan
ts. C
itrus
gre
enin
g ca
n al
so b
e tr
ansm
itted
by
graf
ting
infe
cted
bud
woo
d, b
y do
dder
, and
, pos
sibl
y,
by in
fect
ed s
eed.
Hos
t ran
geC
itrus
gre
enin
g in
Sou
th A
fric
a is
larg
ely
a di
seas
e of
sw
eet o
rang
e (C
itrus
sin
ensi
s), w
ith v
alen
cias
sho
w-
ing
mor
e di
stin
ct le
af s
ympt
oms
than
nav
els.
It is
als
o pa
rtic
ular
ly s
ever
e on
man
dari
ns (
C.
reti c
ulat
a) a
nd
tan
ge
los
(C.
sin
en
sis
x C
. re
ticu
lata
), b
ut
less
on
lem
on
(C
. lim
on
), g
rap
efr
uit
(C.
pa
rad
isi)
an
d s
ou
r or
ange
(C
. aur
antiu
m).
How
ever
, cul
tivar
s su
ch a
s lim
e (C
. aur
antif
olia
), p
om-
elo
(C. g
rand
is),
and
trifo
liate
ora
nge
(Pon
iciru
s tr
ifoli-
ate)
are
tole
rant
to th
e di
seas
e. In
gen
eral
, mos
t citr
us
spec
ies
and
thei
r re
lativ
es a
re s
usce
ptib
le.
Iden
tifi c
atio
n m
etho
ds
The
onl
y de
finiti
ve m
etho
d of
dia
gnos
is o
n tr
ees
sus-
pect
ed to
be
infe
cted
by
the
citr
us g
reen
ing
path
ogen
(H
uang
long
bing
) is
pol
ymer
ase
chai
n re
actio
n (P
CR
) in
an
auth
or is
ed p
lant
dia
gnos
tic la
bora
tory
. In
Sou
th
Afr
ica,
this
can
be
done
by
the
Dep
artm
ent o
f Agr
i cul
-tu
re, F
ores
try
and
Fis
herie
s’ d
iagn
ostic
labo
rato
ries
in
Ste
llenb
osch
.
Con
trol
met
hods
Con
trol
of c
itrus
gre
enin
g ca
n be
ach
ieve
d th
roug
h an
in
teg
rate
d a
pp
roa
ch w
hic
h in
clu
de
s e
rad
ica
ting
in-
fect
ed p
lant
mat
eria
l, in
trod
ucin
g cl
ean
nurs
ery
seed
-lin
gs, a
dher
ing
to r
egul
ator
y m
easu
res
and
elim
inat
ing
inse
ct v
ecto
rs b
y m
eans
of s
yste
mic
inse
ctic
ides
(as
th
ey a
re s
ap fe
eder
s).
Tre
atin
g a
ffe
cte
d t
ree
s w
ith in
ject
ion
s o
f a
ntib
iotic
s a
llevi
ate
s th
e s
ymp
tom
s, b
ut
do
es
no
t cu
re t
he
dis
-ea
sed
plan
ts. P
rom
pt e
limin
atio
n of
dis
ease
d tr
ees
is
stro
ngly
adv
ised
.
The
Asi
an fo
rm (‘
Can
dida
tus
Libe
ri bac
ter a
siat
icus
’) is
th
e m
ost
se
vere
an
d g
eo
gra
ph
ica
lly w
ide
spre
ad
. It
oc
curs
thro
ugho
ut A
sia,
the
Indi
an s
ubco
ntin
ent a
nd
ne
igh
bo
uri
ng
isla
nd
s, t
he
Sa
ud
i Ara
bia
n p
en
insu
la,
Bra
zil,
sout
hern
Flo
rida
, C
alifo
rnia
, C
uba,
Mau
ritiu
s,
Reu
nion
and
Eth
iopi
a.
The
Afr
ican
form
(‘C
andi
datu
s Li
beri b
ac te
r af
rican
us’)
is le
ss s
ever
e an
d is
mor
e re
stric
ted
geog
raph
ical
ly. I
t is
foun
d in
Afr
ica,
sou
th o
f the
Sah
ara.
The
Am
eric
an f
orm
(‘C
andi
datu
s Li
beri
bact
er a
mer
i-ca
nus’
) is
so
far
know
n to
occ
ur in
Bra
zil,
Cub
a, F
lor i-
da, B
eliz
e, M
exic
o an
d D
omin
ican
Rep
ublic
.
Sym
ptom
sC
itrus
pla
nts
affe
cted
by
citr
us g
reen
ing
bact
eria
may
n
ot
sho
w s
ymp
tom
s fo
r ye
ars
fo
llow
ing
in
fect
ion
. In
itial
sym
ptom
s on
a tr
ee in
clud
e th
e ap
pear
ance
of
yello
w s
hoot
s. A
s th
e ba
cter
ia m
ove
with
in a
tree
, the
en
tire
cano
py p
rogr
essi
vely
dev
elop
s a
yello
w c
olou
r.
Th
e t
hre
e f
orm
s o
f b
act
eri
a p
rod
uce
sim
ilar
sym
p-
tom
s.
Th
e m
ost
ch
ara
cte
rist
ic f
olia
r sy
mp
tom
s o
f ci
tru
s gr
eeni
ng a
re b
lotc
hy m
ottli
ng o
f the
leav
es a
nd y
ello
w-
ing
of le
af v
eins
and
sho
ots.
You
ng le
aves
may
dis
play
sy
mpt
oms
that
can
be
mis
diag
nose
d as
sig
ns o
f zin
c de
ficie
ncy.
Old
er le
aves
take
on
the
mot
tling
cha
rac-
Nym
ph o
f th
e A
sian
ci
trus
psy
llid
Nym
ph o
f Afr
ican
citr
us p
sylid
Adu
lt of
the
Afr
ican
citr
us
psyl
lid
Adu
lt A
sian
citr
us
psyl
lidA
dlt
Ai
itT
ypic
al b
lotc
hy m
ottli
ng
sym
ptom
s of
citr
us
gree
ning
on
citr
us s
pp
Fee
ding
dam
age
to c
itrus
le
aves
cau
sed
only
by
the
Afr
ican
citr
us p
sylli
d,
Trio
za e
rytr
eae
Infe
cted
ora
nge
Recommended