350
Deciduous fruit and nut trees and olive
Apple
K.L. Pringle, B.N. Barnes, T.L. Blomefield
The apple – the biblical fruit of temptation. Malus
domestica (family Rosaceae) is one of the most widely
cultivated tree fruits in the world. Together with
pear and quince it is a so-called pome fruit, and has
its origins in western Asia, probably Kazakhstan,
and has been grown for thousands of years in Asia
and Europe. It is now widespread in the colder
and temperate climates of Europe, Asia, North
and South America, Australia, New Zealand, and
southern Africa, mainly South Africa. Through
natural selection and breeding there are more than
7 500 known cultivars of apples, with a wide range
of characteristics, and different cultivars are bred
for various uses. World production in 2009 was
53 million metric tons, with China the largest
producer and South Africa ranked 17th in the world.
In South Africa, most apples are produced in
the Western and Eastern Cape provinces, mostly
where the Mediterranean climate prevails. In 2010
there were some 21 000 ha under production,
and nine cultivars accounted for most production.
Approximately 300 000 metric tons were exported
in the 2009/2010 season.
Apples are subject to infestation by a wide
variety of insect pests. In South Africa, 34 pests
from 13 families occur on apples, although not all
cause economic losses. The most important species
include codling moth, banded fruit weevil, sciobius
weevil, woolly apple aphid, obscure mealybug, and
African bollworm. Another species, apple leaf roller,
occurs only in very limited numbers at present,
probably due to effective natural control, but it has
the potential to increase to economically important
levels. All these pests are discussed in detail in this
chapter; the other less important pests are merely
listed or treated elsewhere in this book.
Page
Common name
Scientific name
352
BUGS
HEMIPTERA
Shield bugs
Family Pentatomidae
Antestia bug
Aphids
Spirea aphid
Cotton aphid
Woolly apple aphid
Common rose aphid
Green peach aphid
Armoured scale insects
Red scale
Circular purple scale
Grey scale
Pernicious scale
Chaff scale
Giant coccids
Cottony cushion scale
Antestiopsis thunbergii (Gmelin)
Feeds on
Coverage
F, Fr
ð
Sh
Sh
Br, R, Sh, T
Sh
Sh
ð
ð
ü
ð
ð
Br, Fr, Sh
Br, Fr, Sh
Br, Sh, Fr
Br, Fr, L, Sh
Br, Fr, Sh
ð
ð
û
ð
û
Sh
ð
Family Aphididae
Aphis spiraecola Patch
Aphis gossypii Glover
Eriosoma lanigerum (Hausmann)
Macrosiphum rosae (Linnaeus)
Myzus persicae (Sulzer)
Family Diaspididae
Aonidiella aurantii (Maskell)
Chrysomphalus aonidum (Linnaeus)
Diaspidiotus africanus (Marlatt)
Diaspidiotus perniciosus (Comstock)
Parlatoria pergandii Comstock
Family Monophlebidae
Icerya purchasi Maskell
Deciduous fruit and nut trees and olive
Page
Common name
Scientific name
Mealybugs
Family Pseudococcidae
Citrophilus mealybug
Long-tailed mealybug
Obscure mealybug
THRIPS
THYSANOPTERA
Thrips
Family Thripidae
Western flower thrips
355
Frankliniella occidentalis (Pergande)
BEETLES
COLEOPTERA
Leaf beetles
Family Chrysomelidae
Fruit nibbler
Long horn beetles
Fig tree borer
Snout beetles, weevils
Black snout beetle
Speckled weevil
Grey snout beetle
Fuller’s rose beetle
Banded fruit weevil
Sciobius weevil
Odontionopa sericea (Gyllenhal)
Phryneta spinator (Fabricius)
Eremnus atratus (Sparrman)
Eremnus cerialis Marshall
Eremnus setulosus Boheman
Pantomorus cervinus (Boheman)
Phlyctinus callosus Schönherr
Sciobius tottus (Sparrman)
Fruit flies
Family Tephritidae
Ceratitis capitata (Wiedemann)
Ceratitis rosa Karsch
BUTTERFLIES, MOTHS
LEPIDOPTERA
Carpenter moths
Family Cossidae
Leaf roller moths
Codling moth
Pear leaf roller
Apple leaf roller
Owlet moths
African bollworm
Fruit-piercing moth
Fruit-piercing moth
Fruit-piercing moth
Fr, Sh
Fr, Sh
ð
ð
Fr, L, Sh
ü
F, Fr, L
ð
F, Fr, L, Sh
ð
F, L
ð
Fr, L
L
L
L, Sh
F, Fr, L, Sh
Bu, F, L
ð
ð
ð
ð
üð
üð
Fr
Fr
ð
ð
Br, T
ð
Fr
Fr, L, Sh
Fr, L, Sh
ü
ð
üð
F, Fr, L, Sh
Fr
Fr
Fr
üð
ð
ð
ð
Family Curculionidae
DIPTERA
Apple trunk borer
Coverage
Family Cerambycidae
FLIES
Mediterranean fruit fly
Natal fruit fly
359
Pseudococcus calceolariae (Maskell)
Pseudococcus longispinus (Targioni
Tozzetti)
Pseudococcus viburni (Signoret)
Feeds on
Coryphodema tristis (Drury)
Family Tortricidae
Cydia pomonella (Linnaeus)
Epichoristodes acerbella (Walker)
Lozotaenia capensana (Walker)
Family Noctuidae
Helicoverpa armigera (Hübner)
Oraesia emarginata (Fabricius)
Oraesia provocans Walker
Serrodes partita (Fabricius)
Feeds on: Br = branches; Bu = buds; F = flowers; Fr = fruit; L = leaves; R = roots; Sh = shoots, T = trunks.
Coverage: ü = treated in this chapter; ð = treated elsewhere in this book (consult the index); û = listed only,
no further treatment in this book; may be listed on other commodities (consult the index).
351
Deciduous fruit and nut trees and olive
Bugs
underground colonies have long, white, filamentous
waxy secretions which give colonies a conspicuous
cottony, white appearance, as illustrated.
Woolly apple aphid
Eriosoma lanigerum
Host plants
Other common names: woolly aphid, apple
root aphid; appelbloedluis (A); pulgãolanígero-das-macieiras (P)
Locally, the major host is apple, though elsewhere
elm trees are an alternate host. They are also very
occasionally found on pear tree roots in South
Africa.
The woolly apple aphid is probably native to eastern
North America, but is now spread throughout the
world’s apple growing areas.
Identification
Egg: Occasionally white, oblong eggs are produced.
However, the females usually give birth to live
nymphs.
Nymph: Dark reddish-brown with a white waxy
covering, about 1.47 mm in length when mature.
The first instar or crawler is mobile. Subsequent
instars are sessile and produce white, waxy secretions
(illustrated), giving rise to the English description
“woolly”.
Woolly apple aphid, Eriosoma lanigerum. Adults and
nymphs, covered in white waxy filaments.
Adult: Dark reddish-brown, of variable size
depending on the number of embryos still in the
ovarioles, and mostly apterous, occurring on both
the roots and aerial parts of apple trees. When
population levels are high, some winged females
are produced that may migrate to other apple
trees. If squashed, the adult gives off a dark red
liquid, hence the Afrikaans name. Both aerial and
Damage
Woolly apple aphid feeds in colonies on the bark of
apple trees, both above ground and on the roots.
Its feeding on the roots causes the formation of
large galls, which can eventually form a crust of
root material just below and on the soil surface, as
illustrated.
K.L. Pringle, Univ. Stellenbosch
Origin and distribution
K.L. Pringle, Univ. Stellenbosch
352
Woolly apple aphid, Eriosoma lanigerum. A crust of
galled apple root material on soil surface, caused by
feeding.
This impairs the penetration of water to the roots
below, and the galls act as a barrier to the uptake of
water and nutrients. In the aerial parts of the trees,
woolly apple aphid establishes colonies in leaf axils
and pruning wounds, where the feeding also results
in galls, often destroying the developing buds in the
leaf axils.
The feeding on the roots results in reduced
growth of all ages of apple trees. The number and
weight of fruit can also be adversely affected by
root infestations. Destruction of developing buds by
aerial infestations also results in a reduction of the
number of fruit. In addition, the aphids can settle
in the stem and calyx ends of the apples and crawl
into the core, resulting in downgrading of the fruit.
Deciduous fruit and nut trees and olive
Life history
In South Africa, the whole life cycle is on apples
where the aphids reproduce parthenogenetically.
No males have been recorded. Both the aerial
and subterranean populations have a number of
overlapping generations per year with five instars
including the adult. There are colonies on the
roots throughout the year. During spring, first
instar crawlers move from the roots up the stem
to produce the aerial infestations. These crawlers
settle in leaf axils and pruning wounds, where they
form conspicuous white colonies, as illustrated. The
crawlers are also blown by air currents, which are
thought to be responsible for most of the within and
between orchard dispersion.
Natural enemies
The most important natural enemy of woolly apple
aphid is a parasitic wasp, Aphelinus mali (Haldeman)
(Aphelinidae). Also originally from eastern North
America, it was introduced into South Africa from
the USA and New Zealand during 1920–1923 and
has become successfully established in all the apple
producing areas of the country where the woolly
apple aphid occurs.
Management
Rootstocks originating from Northern Spy, Merton
and Malling-Merton lines have been used throughout
the world as rootstocks resistant to woolly apple
aphid. However, during the 1960s a woolly apple
aphid biotype surfaced from some local orchards
that had overcome the resistance mechanisms. This
biotype now occurs throughout the apple industry.
Aphelinus mali is an effective biological control
agent of woolly apple aphid, but can be severely
disrupted by the use of certain chemicals applied for
the control of other pests. The wasp normally lays
a single egg inside the woolly apple aphid. When
the egg hatches the larva feeds inside the aphid,
eventually killing it. The larva will then pupate
inside the aphid. Unparasitized woolly apple aphids
appear white as a result of the white, waxy filaments,
while parasitized aphids lose the white filaments and
are clearly discernible as black mummies.
Both subterranean populations and the aerial
populations can be controlled chemically. The
necessity for specific chemical control against woolly
apple aphid can be determined using a standardized
monitoring system. Orchards are divided into blocks
of approximately 2 ha. Twenty-five evenly spaced
trees in these blocks are marked. At least once
every two weeks one half of each of these trees is
examined for colonies in the leaf axils. Each tree
is classified as uninfested, infested with parasitized
colonies or infested with unparasitized colonies. If
there is no parasitoid activity chemical control can
be applied if seven out of the 25 trees are infested.
If there is parasitoid activity the grower should
wait until 13 out of the 25 trees are infested. This
maximizes the chances of biological control by A.
mali, while minimizing the probability of damage.
Further reading
Damavandian, M.R. & Pringle, K.L. 2007; Heunis,
J.M. & Pringle, K.L. 2006; Pringle, K.L. & Heunis,
J.M. 2008.
Obscure mealybug
Pseudococcus viburni
Other common names: pink mealybug,
apple and pear mealybug; appelwitluis (A);
cochonilha-farinhenta (P)
Origin and distribution
The origin of the obscure mealybug, which was
originally described from Australia, is uncertain,
although both Australia, and North and South
America have been mentioned. Besides South
Africa and Zimbabwe in Africa, it is now found in
Australasia and certain parts of Europe and Asia
while also being widespread in North and South
America.
Identification
The obscure mealybug, Pseudococcus viburni, has in the
past also been referred to as P. capensis Brain, which
was described from the Cape, P. obscurus Essig (hence
its common name) and P. affinis (Maskell), all three
being junior synonyms of P. viburni. In addition,
the obscure mealybug was mistaken for Pseudococcus
maritimus (Ehrhorn) in the past and became well
known in South Africa and elsewhere by that name.
The true P. maritimus, however, is a distinct species
353
Deciduous fruit and nut trees and olive
stout, slightly curved snout (rostrum) 1–2 mm long,
which is black and shiny at its tip.
B.N. Barnes, ARC
evident on the aerial parts of host plants. Damage
by adults to leaves and fruits includes shot-holing of
leaves, leaf and stem notching, shoot and fruit-stem
notching, blossom and shoot-tip feeding, and fruit
scarring (illustrated). In the case of fruit scarring,
economic damage to commercial fruit often results,
requiring weevil management. On apples and
nectarines, most fruit feeding takes place soon after
adult emergence, reaching a peak in November/
December.
Banded fruit weevil, Phlyctinus callosus. Adult.
Host plants
Phlyctinus callosus is polyphagous, feeding on a wide
variety of mono- and dicotyledonous weeds, grasses,
herbs and woody plants. It is not consistent in the
type of plants it feeds on in different areas and
countries. Larvae feed on the roots of various host
plants, with a preference for broad-leaved weeds
and ornamentals, such as narrow-leaved ribwort,
Plantago lanceolata (Plantaginaceae); hairy wild
lettuce, Hypochaeris radicata (Asteraceae); bur clover,
Medicago sp. (Fabaceae); sow thistle, Sonchus oleraceus
(Asteraceae) and hen and chickens, Chlorophytum
comosum (Asparagaceae). They also damage roots of
grapevine.
Adults feed on the fruit, leaves, shoots and fruit
stalks of most deciduous fruit and grapevines,
including some berries (e.g. blueberry, Vaccinium
corymbosum), as well as the leaves and stems of a wide
variety of weeds and grasses. As with the larvae,
broad-leaved plants are preferred, and particularly
those with more fleshy leaves such as succulents.
Examples: small mallow, Malva parviflora (Malvaceae);
bur clover; narrow-leaved ribwort; sow thistle;
purslane, Portulaca oleracea (Portulacaceae); sour fig,
Carpobrotus spp. (Aizoaceae); chrysanthemum species
(Asteraceae), and the succulent genera Cotyledon
and Crassula (Crassulaceae). In Australasia both the
adults and larvae damage vines, apples, nectarines,
plums, walnuts, olives, strawberries, potatoes,
asparagus, carrots, parsnips, lucerne and various
ornamentals.
Damage
The effects of root-feeding by the larvae are seldom
L. van Wyk
356
Banded fruit weevil, Phlyctinus callosus. Adult weevil
damage to an apple.
The banded fruit weevil is one of the key pests
on deciduous fruit and vines due to the feeding
damage done by the adults to the fruit. Adults
can be inadvertently packed with export fruit
causing quarantine problems. It is an international
phytosanitary pest.
Life history
Phlyctinus callosus is adapted to hot, dry summers
and wet winters. There are either one or two
generations per year, determined by the type of
summer irrigation applied combined with the type
of orchard or vineyard ground-cover management
employed. In its natural habitat outside summerirrigated fruit orchards, the weevil is likely to have
one generation per year.
Eggs are laid in batches of about 20 or more,
mostly in hollow stalks (dead or alive) or between
the leaf sheaths of host plants and sometimes in
leaf litter. Oviposition occurs throughout the year,
with peaks in spring (August to October), summer
(December and January) and autumn (March to
May). The incubation period is 6–15 days. Peak
Deciduous fruit and nut trees and olive
larval populations occur from June–October, and
where a second generation is present, again from
January–April. The larval duration is from 2–5
months, depending on the season. Most larvae
pass through 5–8 instars, but up to 11 can occur.
The prepupa constructs an earthen chamber in the
upper 100 mm of the soil in which it pupates. The
pupal duration is from 1–3 weeks.
Most adults emerge from the soil between
October and December. Where the second generation is present, the adults emerge between March
and May. Adults are crepuscular, seeking shelter
during the day, and they often feign death when
disturbed. Overwintering takes place in the larval
stage, and adults emerging in one season can survive
the winter and be found on host plants the following
season.
Natural enemies
Curculionids as a group have a wide range of natural
enemies including protozoans, entomopathogenic
fungi, entomopathogenic nematodes, mites, hymenopteran parasitoids, beetles, flies, ants, spiders and
birds.
The following species have been recorded
as natural enemies of P. callosus in South Africa:
the mymarid egg parasitoid Cleruchus sp.; a braconid,
Perilitus sp.; the nematodes Heterorhabditis spp. (Heterorhabditidae), Steinernema spp. (Steinernematidae) and
an unidentified mermithid that attack the larvae;
mites of the families Trombidiidae and Erythraeidae
(Leptus sp.) that parasitize the adult weevil; driver
ant Dorylus helvolus (Linnaeus), and guineafowl.
Judging from the size of P. callosus populations and
associated damage in commercial fruit plantings,
especially in uncontrolled conditions, the impact of
these organisms on P. callosus populations appears to
be marginal.
In Australasia the entomopathogenic fungus
Beauvaria bassiana, and nematodes Heterorhabditis
bacteriophora Poinar and H. heliothidis (Khan, Brooks
& Hirschmann), as well as chickens, turkeys and
guineafowl, have been recorded as natural enemies.
Management
Management of P. callosus is difficult as the immature
stages are out of reach of conventional control
interventions, and the adults are hardy and not easily
killed by the more environmentally-compatible
insecticides. Natural control by biological agents
appears to be limited. An integrated management
approach using chemical and/or physical methods,
or particle-film technology, together with certain
cultural control practices, offers the best solution. As
P. callosus occurs sporadically, even at orchard level,
decisions on whether or not to intervene should be
based on the results of a programme to monitor the
adults.
Certain synthetic pyrethroids applied as fullcover sprays to the canopy of fruit trees or vines
reduce adult populations, although these products
are generally not compatible with integrated pest
management programmes. Other insecticides may
also give some measure of control. Not all products
are permitted to be applied to any particular crop.
As the adults are flightless, exclusion barriers
secured to the trunks of fruit trees or vines have
been successful to varying degrees, by limiting access
to the trees. These commonly comprise low-density
fibre (batting) strips, which can also be soaked in a
synthetic pyrethroid, or a sticky substance smeared
on a plastic strip secured to the trunk.
Kaolin particle film technology: Finely-milled
95% kaolin clay in aqueous suspension can be
sprayed onto the canopy of certain types of fruit
trees, covering all the leaves and fruit with a fine
layer of kaolin. It acts as a repellant to adult weevils
which find it difficult to walk on this surface and to
eat fruit covered by it.
As the adults are flightless, control of all weeds
and grasses growing into the host plants (e.g. apple
trees), or host plant branches hanging onto the
ground, limits the number of weevils that can access
the plant and cause economic damage. Encouraging
guineafowl or chickens, which can scratch out
and eat adults, larvae and pupae from the soil, in
commercial plantings, can reduce the weevil’s
economic impact. Discing of the soil between
vineyard rows to destroy larvae and pupae has been
advocated in Australia.
Further reading
Barnes, B.N. 1989; Barnes, et al. 1996; May, B.M.
1966.
357
Deciduous fruit and nut trees and olive
Host plants
Sciobius weevil
Sciobius tottus
A supplementary account of this weevil
appears in the chapter on berry pests
Known hosts of this weevil include apple, pear,
plum, maritime pine, Pinus pinaster (Pinaceae); Cape
beech, Myrsine melanophloeos (Myrsinaceae); silver
birch, Betula pendula (Betulaceae), and sage bush,
Buddleja salviifolia (Scrophulariaceae).
Damage
Origin and distribution
This weevil is endemic to South Africa where it
occurs in the eastern part of the country. It is an
introduced pest on the Atlantic Ocean island of St.
Helena.
Identification
Egg: Oblong, pale yellowish, approximately 1.0 x
0.5 mm, laid in batches of 5–25, often cemented
between leaves.
Larva: A C-shaped, legless grub, with an orange
head capsule and black jaws, and bearing many
longish setae. The first instar is about 0.5 mm in
length, reaching 7–11 mm in the final instar. Older
instars are creamy-white. Subterranean, feeding on
the roots of host plants.
Pupa: Naked, creamy-white, 8–9 mm long with
stout, hooked bristles. Soft-bodied and easily injured.
Adult: Illustrated. Flightless, about 8–12 mm long,
with very long, slender antennae, more than half the
length of the body. The rostrum is short and broad,
and the pronotum has small, rounded tubercles;
elytra shiny brown to dark brown with regular
longitudinal rows of small, closely-spaced tubercles,
and short buff-coloured hairs. Legs long and slender,
the last tarsal segments long and arched. Varies
much in size and colour.
In 1996 apple growers in the Langkloof reported
sudden and serious damage being caused by a weevil
to the buds, blossoms and leaves of apple trees.
The weevil was identified as S. tottus, not previously
recorded as a pest of fruit. Shortly thereafter, similar
damage to apple, pear and plum was reported from
the Elgin and Stellenbosch areas of the Western
Cape. Population explosions resulted in almost
complete loss of buds, blossoms and young leaves
in some orchards, resulting in serious crop losses.
However, damage to fruit by S. tottus has not been
recorded. Subsequently, the size of populations
and associated damage in orchards decreased
significantly.
Life history
The life history of this weevil is similar to that of P.
callosus, except that eggs are laid on leaves cemented
together during oviposition. In apple orchards there
appears to be only one generation per year. Larvae
feed on roots of weeds and possibly also on fruit
trees, and pupate in the top 100–150 mm of the soil.
Adults start emerging at the end of August, earlier
than P. callosus, with peak emergence in September
and October. Few adults emerge after January.
Adults are present on the trees between September
and May/June, and are more active after dusk,
seeking shelter during the day.
Natural enemies
J. de Waal
358
Sciobius weevil, Sciobius tottus. Adult.
A trichogrammatid parasitoid identified as
Oligositoides sp. has been reared from S. tottus eggs
from an apple orchard in Grabouw, Western Cape.
It is likely that, as with P. callosus, entomopathogenic
nematodes and fungi reduce larval and pupal
populations. Guineafowl will most probably prey on
adults and immature stages on the orchard floor or
in shallow ground.
Management
Management practices are the same as for P. callosus.
Deciduous fruit and nut trees and olive
The use of full-cover synthetic pyrethroids on the
trees reduces adult populations, and trunk barriers
will reduce the number of adults gaining access
to the trees. Bridging control (management of
tall weeds and grasses and low-hanging fruit-tree
branches) will also reduce the number of adults in
the trees.
Moths
Codling moth
Cydia pomonella
Other common names: kodlingmot (A); traçada-macieira (P)
thoracic shield and dark brown head capsule. There
are five larval instars.
Pupa: About 12 mm long, light brown in colour,
changing to dark brown or black prior to adult
emergence; in a silken cocoon beneath loose bark or
in sheltered crevices on the tree.
Adult: Illustrated. About 10–15 mm long, with the
wings folded over the body when at rest. It is a nondescript ash-grey colour, but on close inspection the
forewings are crossed with alternating fine, wavy
grey and white bands with a tinge of brown. A
distinctive metallic bronze-coloured patch is clearly
visible at the tip of each forewing. The hind wings
are uniformly brownish with no distinct markings.
Origin and distribution
C. Griffiths, M. Picker
Codling moth is thought to be native to Central
Asia. Today it is found on all continents wherever
apples and pears are grown, except in Japan and
Western Australia.
Identification
The New Zealand Inst. for Plant & Food Res. Ltd.
Egg: Oval and flat, about 1 mm in diameter,
translucent white when first laid. As it matures a red
ring develops around the perimeter, and just before
hatching the black head of the larvae is visible
through the transparent shell.
Codling moth, Cydia pomonella. Larva feeding on a
seed inside an apple.
Larva: Illustrated; 2–3 mm long when newlyhatched, with a creamy-white body and a black
head capsule. When mature it is 14–20 mm long,
with a smooth pink body and a speckled, brown
Codling moth, Cydia pomonella. Adult.
Host plants
The preferred host plants are pome fruits, especially
apple, pear and quince. Other less important
cultivated host plants are crab apple, apricot, peach,
plum, prune, cherry and walnut. Infestation of these
fruits often takes place when in close proximity to
the primary host plants.
Damage
Although young larvae may feed on leaf tissue and
have been reported to bore into twigs, they are
primarily internal fruit feeders. Damage is classified
as stings (shallow entries where the larva damages
the surface of the fruit before dying or trying
another point of entry) or deep entries (when the
larva tunnels into the core of the fruit and feeds on
the seeds, as illustrated). Although shallow entries
early in the season can result in severely malformed
fruit, when caused later in the season they result in
the fruit merely forming a shallow callous at the
entry point. However, both types of damage render
the fruit unmarketable.
359
Deciduous fruit and nut trees and olive
J. de Waal
360
Codling moth, Cydia pomonella. Larval damage to an
apple, showing excreted frass.
Fruit infestation can take place from fruit
set right through to harvest. During early fruit
development in spring, up to 80% of first instar
larvae enter fruit through the calyx. Only toward
the end of November do an increasing number of
larvae enter through the sides of the fruit. Generally
the first instar larva stays and feeds just under the
epidermis until reaching the second instar, when
it bores through the flesh of the fruit to the core,
also feeding on the seeds. During feeding the larva
excretes granular brown frass, some of which is
pushed out of the tunnel entrance (illustrated).
Codling moth is a key pest of apples and pears
worldwide. Since it was first reported in South Africa
in 1885, codling moth has remained a major pest of
apples and pears and, to a lesser extent, of apricots.
If uncontrolled it has the potential to destroy the
entire crop. It is an expensive pest to control – in
2011 the estimated cost for codling moth control
in South African apple and pear orchards was R67
million.
Life history
Females each lay an average of 150 eggs, singly on the
wood, leaves or fruit. Depending on the temperature,
incubation lasts 6–16 days, and the larval period
21–28 days. Fully grown larvae overwinter in an
inactive state referred to as diapause – a state of
delayed biological development. Diapause allows
the insect to synchronize its seasonal activity with
the presence of developing fruits on its host trees,
and is generally induced by shortening day-length
and a fall in temperature during autumn. Mature
larvae about to enter diapause leave the fruit and
spin thick, silken cocoons in sheltered places – under
loose bark, in crevices and pruning cuts on the tree,
on support poles, on large prunings on the ground
and even in bulk bins used during harvest. Few
larvae spin cocoons on the soil, and of those that
do there is a high mortality. They spend the winter
in this state of larval dormancy, which is broken
by an increase in temperature and photoperiod in
spring. After completion of larval development, and
pupation which lasts 14–21 days, the emergence of
adult moths coincides with blossom and fruit set of
the host plant.
The first spring moths begin to emerge in
September, about a month prior to full bloom.
Mating can take place on the same day that the
adults emerge. Moths are most active prior to and
just after sunset, when most of them mate. The
adults live from 11–22 days. The total developmental
time from egg to adult of non-diapause individuals
is from 40–65 days.
There are three larval generations per year in
South Africa, though a partial fourth generation can
occur. In successive generations, progressively more
larvae enter diapause until the third generation (or
fourth if there is one), when all larvae enter diapause.
Natural enemies
The following indigenous South African parasitoids
are known: two larval parasitoids, Pimpla albipalpis
Cameron (also attacks pupae) and Eriborus pomonellae
(Cameron), which belong to the Ichneumonidae,
and the trichogrammatid egg parasitoid Trichogrammatoidea lutea Girault. Several ichneumonid
and braconid parasitoids were introduced into the
western Cape from France, Italy, USA and Canada
in earlier years for the biological control of codling
moth. Of these, only the braconid egg-larval
parasitoid, Ascogaster quadridentata Wesmael became
established.
Larval predators recorded from South Africa
include the cricket Gryllus bimaculatus De Geer
(Gryllidae), the bugs Coranus papillosus (Thunberg),
Pirates sp. (Reduviidae) and Diploxys hastata (Fabricius)
(Pentatomidae), the carabid beetle Chlaenius dichrous
Wiedemann, and the ants Dorylus helvolus (Linnaeus)
and Linepithema humile (Mayr).
The use of entomopathogenic nematodes in
integrated pest management is increasing, and
commercial nematode products are available
Deciduous fruit and nut trees and olive
Common fruit chafer
Pachnoda sinuata
Other common names: garden fruit chafer,
black-and-yellow fruit chafer; tuinvrugtetor (A);
besouro-das-frutas (P)
the dorsum of the body essentially black with
yellow sides, the elytra each with a transverse yellow
band and yellow posterior margin, as illustrated;
ventral surface yellow. Not to be confused with
CMR beetles, which have broad black and yellow
transverse bands.
Additional accounts of fruit and flower
chafers are given in the chapters on tomato,
rose and protea pests
Origin and distribution
Identification
Common fruit chafer, Pachnoda sinuata. Pupa.
Host plants
The common fruit chafer feeds on a wide variety
of indigenous and exotic plants, including soft, ripe
fruits, such as peach, plum, apricot, fig and papaya,
and many kinds of flowers and ornamentals, and
even vegetables such as tomato.
M. Wohlfarter
Egg: Spherical, white, about 1.5–2.0 mm in
diameter; laid in decaying organic matter.
Larva: Illustrated. Creamy-white in older instars
with a brown head capsule, three pairs of short
thoracic legs and a relatively long, stout, segmented
abdomen, which stiffens when handled. The distal
end of the abdomen is often dark-coloured from
ingested organic matter. Soil-dwelling, up to 40 mm
in length when mature, with strong mandibles which
can deliver a painful nip. When placed on a flat
surface it turns on its back and progresses rapidly
with an undulating motion.
Lambert Smith
Pachnoda sinuata is indigenous to southern Africa
and distributed throughout sub-Saharan Africa,
occurring as far north as Somalia.
M.C. Knipe, ARC
328
Common fruit chafer, Pachnoda sinuata. Larvae.
Pupa: Yellowish-brown, found in a hard, eggshaped earthen cell, constructed from soil and plant
debris, as illustrated.
Adult: A typical fruit chafer, about 25 mm long,
with a robust, flattish, almost rectangular body
with a smooth surface. Colouration variable but
Common fruit chafer, Pachnoda sinuata. Adults feeding
on a fig.
Damage
Adults feed on the flesh of ripe fruit that has been
mechanically damaged in some way, such as by
birds, enlarging existing wounds, with often more
than one adult feeding on a fruit as illustrated. On
flowers, adults feed especially on the inflorescences
of compound flowers. Flowers and fruit can be
wholly or partially destroyed.
This beetle is an abundant and familiar garden
pest, which wholly or partially destroys flowers and
Deciduous fruit and nut trees and olive
A.P. Marais
and a conspicuous oblique white streak across the
middle; wingspan about 60–85 mm; hind wings
orange with a central black spot and a continuous
black border. Male forewings creamy-brown to pale
green with darker shades.
A.P. Marais
Fruit-piercing moth, Pericyma scandulata. Adult.
Damage
The damage caused by fruit-piercing moths is
similar for all species. Large numbers of moths fly
from surrounding veld into orchards and vineyards
at night and feed on ripening or ripe fruit. Economic
damage (illustrated) to fruit is caused when moths
pierce the skin with their barb-tipped proboscis
to suck out the sap. This leaves a spherical, dry
spongy area about 10 x 10 mm beneath an ovalshaped feeding hole about 1–2 mm in diameter,
which is later evident as a darker area under the
skin. Once the skin of the fruit has been pierced,
the flesh becomes vulnerable to secondary infection
from micro-organisms, and insects such as vinegar
flies, which in turn leads to fruit rot, accelerated
ripening and early fruit drop. When damage to the
fruit occurs shortly before harvest and the flesh of
the fruit has not yet discoloured around the feeding
site, the pinprick holes are not easily observed.
Rotting of the flesh may then only take place after
harvest and packing. This can lead to downgrading
or rejection of whole consignments of fruit with
increased packing and processing costs.
Fruit-piercing moth, Eudocima materna. Adult.
Apart from peaches there are many alternate wild
host plants of these moths, some of which include
the following: Serrodes partita larvae feed extensively
on the jacket-plum, Pappea capensis (Sapindaceae),
which grows wild over large areas of the Karoo.
In addition, it has been recorded from species
of Deinbollia (Sapindaceae), Grewia (Malvaceae),
Jasminum (Oleaceae) and on Leptospermum laevigatum
(Myrtaceae). Larvae of O. emarginata and O. provocans
feed on Cissampelos capensis, C. torulosa and Stephania
sp. (Menispermaceae) as well as Adenia gummifera
(Passifloraceae). Pericyma scandulata larvae feed on the
leaves of the thorn tree, Acacia (=Vachellia) karroo, and
E. materna larvae have been recorded from orange
grape creeper, Tinospora caffra, Dioscoreophyllum sp.,
Rhigiocarya sp. (Menispermaceae) and Erythrina sp.
(Fabaceae). Fruit-piercing moth adults as a group
feed on the sap of many deciduous and subtropical
fruits, as well as wild fruits such as prickly pear and
certain berries.
ARC, Infruitec-Nietvoorbij
Host plants
Peaches damaged by feeding fruit-piercing moths.
Serrodes partita, P. scandulata, O. emarginata and O.
provocans are responsible for most of the damage to
fruit in the Western and Southern Cape. However,
S. partita is by far the most important pest, accounting
for 68–99% of all fruit piercing moths recorded in
surveys. Serious economic losses are caused when
populations attain epidemic proportions, which in
the case of S. partita occur when good rains fall in
the areas where jacket plum grows. Such conditions
are cyclic and occur in the Karoo on average every
337
Deciduous fruit and nut trees and olive
the elytra, and patches of the same colour on each
side of the thorax. The thorax has four conical
projections. There are tufted humps on the anterior
part of the elytra, and also numerous tufts on the
posterior section. The long antennae are unusual
in that they are curled backwards at the tip, with
segments of varied lengths, and have a conspicuous
plume of hairs at the distal end of the third segment.
the year. Adults emerge during November and are
absent from March to August.
Natural enemies
An unidentified parasitic wasp has been documented
attacking the eggs of the sombre twig pruner, with
high levels of parasitism being observed.
Management
Host plants
The known host plants of the beetle are restricted
to the olive family (Oleaceae) and include cultivated
as well as wild olive, jasmine and species of Fraxinus
(ash) and Ligustrum (privet).
The only management option currently available is
to remove and destroy infested plant material.
Further reading
Fuller, C. 1913.
Damage
Larvae bore upwards and downwards in shoots
(illustrated), ejecting frass from a number of vent
holes, and causing shoot tips to die off. Though not
widespread, nor a serious pest of cultivated olives,
the sombre twig pruner has the potential to increase
in pest status, especially if trees are stressed. In South
Africa it is also very destructive to Ligustrum hedges.
Olive flea beetles
Argopistes capensis, A. oleae and
A. sexvittatus
Other common names: olive beetles;
olyfkewers (A)
Origin and distribution
Argopistes capensis and A. oleae were originally described from the Western Cape and appear to be
restricted in their distribution to this region of South
Africa. Argopistes sexvittatus has a wider distribution
and has been recorded from various localities across
South Africa and also from Namibia.
P. Addison
400
Sombre twig pruner, Cloniocerus kraussii. Larval damage
to a shoot of an olive tree.
Life history
The life history of the beetle on cultivated olives has
not been documented. The following account of its
occurrence on Ligustrum is by Fuller (1913).
Eggs are inserted singly into thin shoots, about
100–300 mm from the tip, in a cavity beneath the
bark made by the female’s mandibles. The eggs
hatch after about 12 days and the young larvae
start to tunnel in the centre of the shoots. Larvae
complete their development and pupate in the
shoots, and are present in host plants throughout
Identification
Apart from the three above-mentioned species there
are at least two additional, but undescribed, species
of Argopistes that feed on olives in southern Africa.
Eggs: Approximately 2 mm in length; recognizable
by the hard, brown protective covering made from
excrement; laid singly or in clusters on leaves.
Larvae: First instar larvae are just over 2 mm in
length and yellow in colour. Fully grown larvae are
about 7 mm in length, and deep yellow in colour
except for the head, thorax and legs which are brown
to black. Larvae are slightly flattened and give the
appearance of being serrated when viewed dorsally.
The last abdominal segment bears an abdominal leg
or pseudopod.
Pupae: Yellow in colour and soft-bodied; found in
Deciduous fruit and nut trees and olive
A.P. Marais
the soil (illustrated).
N. Mkize
Olive flea beetle, Argopistes oleae. Adult.
A.P. Marais
Adults: Small, convex, oval-shaped beetles,
ranging from about 4.0–5.0 mm in length, with
the head mostly hidden under the thorax. Species
can usually be differentiated primarily by the
colouration of the elytra, although there may
be considerable colour variation in two of these
species. A. sexvittatus (illustrated) is overall yellowishbrown with each elytron with a single, dark, narrow,
median longitudinal band and dark inner and lateral
margins; specimens are known in which the elytra,
and sometimes also the thorax, are entirely bluishblack; A. oleae (illustrated) differs from A. sexvitattus in
that the head and thorax are usually black and the
black longitudinal band and margins of the elytra
are much broader, although mostly bluish-black
specimens are also known; A. capensis (illustrated) is
uniformly yellowish-brown with a golden tinge and
faint, irregular darker brown longitudinal stripes on
the elytra. Adults of these beetles can be confused
with ladybird beetles, but differ from the latter in
having strongly-developed hind legs, which they use
for jumping, hence their common name, flea beetles.
Olive flea beetle, Argopistes sexvittatus. Adult.
A.P. Marais
Olive flea beetle, Argopistes sp. Pupa in an earthen cell.
Olive flea beetle, Argopistes capensis. Adult.
Host plants
The genus Argopistes is strictly associated with plants
of the olive family, and the species treated here have
only been recorded from wild and cultivated olives.
Damage
Larvae and adults have a preference for young
leaves especially near the top of the tree. Larvae
mine between the upper and lower epidermis of
young leaves, forming long, meandering chlorotic
and necrotic streaks. Adults chew small holes in
the upper surface of leaves (illustrated). Feeding
damage on young leaves in particular can cause
malformation of the leaves as they mature. Adults
also chew small, shallow holes principally in young
fruits, which scar the olives and render them
unacceptable for processing. In heavily infested
groves, foliage becomes very sparse and trees can
be completely defoliated. Adults on olive trees are
usually found above a height of about 600 mm from
the ground.
The species treated here are particularly
troublesome on cultivated olives in the Western
Cape, and there appear to be differences in the
susceptibility of various cultivars to beetle damage.
401
Deciduous fruit and nut trees and olive
sprays are registered as early season applications
against olive beetles, and should be timed to target
adults or newly emerged larvae before they enter the
leaves in spring.
Further reading
Myburgh, A.C. 1952.
Flies
Olive flea beetle, Argopistes sexvittatus. Adult feeding
damage to an olive leaf.
Life history
Eggs are laid singly or in small groups (up to ten
in some species) on the upper and lower surfaces
of leaves, and are protected by a hard covering
formed by the beetle’s excrement. The eggs hatch
after about three weeks in spring and two weeks in
summer. The larvae mine between the upper and
lower leaf surfaces and the larval stage lasts about
three weeks in spring, but probably less during the
warmer months. The mature larva enters the soil,
burrowing to a depth of about 25–50 mm where it
pupates in an earthen cell (illustrated).
Three generations per year may occur. Adults
can be found throughout the year, while larvae
are found from September to April. Oviposition
occurs from August until late October, and larvae
emerge from September until mid-November.
Second generation eggs are laid during November
with larvae mining leaves from December onwards.
Adults of the final generation emerge during March
and early April and overwinter as adults.
Natural enemies
The parasitic wasp Colastes inopinatus Belokobylskij
(Braconidae) is known to parasitize the larvae of
Argopistes species in South Africa. However, the rate
of parasitism was found to be low.
Management
Olive beetles show no significant attraction to
olive leaf volatile compounds, and no other known
monitoring methods are currently in place. Chemical
Olive fruit fly
Bactrocera oleae
Other common names: olive fly; olyfvlieg (A);
mosca-da-azeitona (P)
Origin and distribution
Although the olive fruit fly was originally described
from Italy, it is probably of African origin, and
currently distributed wherever cultivated and wild
olives are found: the Mediterranean basin, South
and Central Africa, Canary Islands, Réunion Island,
Near and Middle East, Northern India, California,
and Central America.
Identification
M.W. Johnson
P. Addison
402
Olive fruit fly, Bactrocera oleae. Adult female.
Egg: Approximately 0.7–1.2 mm long, whitish,
elongate and slightly flattened in the mid-section;
laid in fruit.
Larva: A typical fly maggot, 6.5–7.0 mm long
when mature, yellowish-white in colour, elongate
and sub-conical in shape. The various instars are
differentiated by their cephalo-pharyngeal structure.
Pupa: A typical fly puparium, 3.5–4.5 mm in