PLANT PROTECTION 1 – Pests, Diseases and Weeds

PLANT PROTECTION 1 – Pests, Diseases and Weeds
Sanitation reduces breeding sources.
You are required by law in prescribed areas to:
Remove unwanted or regularly unharvested
fruit trees and orchards around sheds, boundary
fences. There may be specific requirements in
some regions for some crops, eg quince.
Treatment of alternative fruiting hosts
and removal of wild hosts in and around orchards
help reduce numbers.
Collect and destroy immediately all ripe,
fallen fruit and tomatoes. Remove all infested
fruit from trees and tomato plants at intervals
not exceeding 3 days, to eliminate breeding sites.
Remove any late hanging fruit. Keep ground
beneath trees and around tomato crops free from
long grass and weeds. Destroy fruit by either:
– Boiling for at least 10 minutes. Take care.
– Burning (if permitted).
– Soaking for at least 3 days in water topped with
kerosene. Dispose of fruit after treatment.
– Placing in water in a covered container for 3 days.
– Securing fruit inside a plastic garbage bag and
exposing the bag to sun for 3 days, and disposing
in the garbage. Suitable for home gardeners. Could
this be buried in the soil?
– Treating with an approved insecticide, prior to
burying. Do not bury untreated fruit as this does
not kill the maggots and adult flies can emerge
from pupae as deep as 1 meter.
– Slash between rows to destroy fruit.
– Practice good packing shed hygiene with
thorough inspections to remove any infested fruit.
– Special arrangements may be negotiated with
organic growers in eradication areas to remove all
fruit from a property not treated. Remember it is
only possible to grow organic fruit because
neighbours co-operate in fruit fly eradication.
What are your local regulations?
Biological control.
Natural controls. Fruit flies also infest the fruit
of native plants; native parasites and predators,
some of which can be mass reared and released to
help provide control of fruit fly populations.
– Parasitic wasps commonly lay eggs in fruit fly
eggs and maggots but do not significantly reduce
fruit fly numbers.
– Predators of adult fruit flies include the assassin
bug, praying mantises, spider and birds.
.
SIT (Sterile Insect Technique) is the large
scale breeding and release of sterile male flies
which mate with wild female flies in the field
producing non-viable eggs leading to eradication.
The method is species specific. Fruit flies are
sterilized by exposing pupae to gamma radiation.
– Used for most outbreaks of QFF in SA following an
initial baiting program. May be available for Medfly
control in SA and with baiting techniques to
eradicate MedFly in WA.
– Medfly is harder to eradicate than QFF because it is
less responsive to bait.
New lures for female Bactrocera spp. of fruit
flies being researched will improve monitoring
and so protect current markets for fresh produce.
Resistant varieties.
Late ripening fruits are very susceptible. Early
ripening fruits act as a source of infestation of later
ripening fruits.
Plant quarantine.
Australian Quarantine & Inspection Service
(AQIS) controls the entry of exotic fruit flies
(page 66) into Australia, using a combination of
X-ray units, detector dogs, physical inspection
and quarantine surveillance (trapping, regular host
fruit surveys of high risk species, eg guava, mango).
– Northern Australian Quarantine Strategy
(NAQS) trapping program detects exotic fruit fly
incursions in the Torres Strait and from Asia, eg
Asian Papaya fruit fly, melon fruit fly and
Bacterocera trivialis which are directly related to
weather patterns. This warning detection
program uses traps baited with lures to detect lureresponsive
exotic fruit flies. Exotic fruit flies in the
Torres Strait are eradicated.
– Fruit is imported from fruit-fly pest free areas
overseas, based on results of trapping, climatic data
and verification visits to pest-free areas, etc.
Interstate & Regional Plant Quarantine
Checkpoints throughout Australia prevent spread
of fruit fly into fruit fly-free regions.
– Tasmania and NZ are free from Medfly and QFF,
as is SA.
– Medfly occurs in WA except in the Ord River
Irrigation Area which has area freedom status.
– QFF is present in NT, Qld, NSW and Vic.
– The Fruit Fly Exclusion Zone (FFEZ). Comprises
parts of NSW, Victoria and SA (Fig. 43).
www.agric.nsw.gov.au
–Maintenance of the FFEZ and other Fruit Fly
Free Areas involves:
Roadblocks to confiscate fresh fruit and
vegetables. Warning signs and disposal bins are
located on most roads leading into the FFEZ.
Fruit fly traps to detect outbreaks (monitoring).
Eradication of detected outbreaks.
Control of movement of infested fruit by regional
Quarantine Regulations within Australia.
Coordination and management of the FFEZ by
the TriState Fruit Fly Committee involving
Commonwealth, NSW, Vic, SA and industry.
–Recognition of fruit fly free areas by overseas
countries means that fruit can be exported without need
for costly treatments, eg citrus to Japan.
–Pest Quarantine Areas for fruit fly incursions, eg
papaya fruit fly in Queensland, limited its spread and
facilitated monitoring and eventual eradication.
Fig. 43. Fruit Fly Exclusion
Zone (FFEZ). Quarantine areas
marked with dots, other quarantine
areas are prescribed as necessary.
If you find maggots
in fruit or vegetables
in areas considered
free of fruit fly
contact your local
Department of
Agriculture for
advice.
Fig. 44. Examples of interstate
quarantine leaflets.
Insects and allied pests - Diptera (flies) 71