Identification, Symptoms, Nature Identification, Symptoms, Nature of Damage ofof Damage of Mango Fruit Fly, Mango Fruit Fly,

Stone/Nut Weevil Stone/Nut Weevil and and Pulp weevilPulp weevil

BackgroundBackground

India is the world’s second largest producer of fruits and India is the world’s second largest producer of fruits and vegetables. vegetables.

Mango is known as king of fruits in India and has Mango is known as king of fruits in India and has largest acrage and production in the world but its export largest acrage and production in the world but its export is mainly hindered by quarantine concerns.is mainly hindered by quarantine concerns.

Fruit flies, stone weevil and pulp weevil infesting Fruit flies, stone weevil and pulp weevil infesting mango fruits in India are of quarantine concerns to many mango fruits in India are of quarantine concerns to many countries countries

viz., Japan (fruit flies) ,USA (fruit flies &viz., Japan (fruit flies) ,USA (fruit flies &

Stone weevil) etc.Stone weevil) etc.

Fruit flies (Diptera: Tephritidae)Fruit flies (Diptera: Tephritidae) are among the world’s most serious pests of horticultural crops due to their direct economic impact as females oviposit inside the fruits and consequently young larvae feed on the pulp thus render them unmarketable.

The fruit flies comprise over 4,000 species distributed globally throughout all the temperate, subtropical and tropical climatic zones. The genus Bactrocera includes about 500 species.

In India, eight species of genus Bactrocera are identified among quarantine pests related to mango.

Fruit fly laying eggs Larvae after hatching feeding on pulp

Bactrocera dorsalis B. zonata B. cucurbitae

B. Correcta B. diversa B. tau

Important Fruit flies

In India, Oriental fruit fly B. dorsalis Hendel is the most destructive fruit fly of mango, followed by Peach fruit fly B. zonata Saunders and Guava fruit fly B. correcta Bezzi

The flies attack fruits at different stages of maturity but damage is more obvious at harvest maturity stages.

B. Dorsalis B. zonata B. correcta

IdentificationIdentification

Adult Adult – – Reddish brown with transparent wingReddish brown with transparent wing

LarvaLarva – – creamish yellow apodous maggots. creamish yellow apodous maggots.

PupaPupa- ranges in color from dull red or - ranges in color from dull red or brownish yellow brownish yellow

SymptomsSymptoms

The female insert eggs in small clusters inside the mesocarp of the fruits

Ovipunctures and oozing of fluidOvipunctures and oozing of fluid

After hatching larvae feeds on the pulp which appears normal from outside.

Nature of DamageNature of Damage

Brownish rotten patches on Brownish rotten patches on fruits.fruits.

Fruits finally drops down.

The larvae pupate in soil (5-10 cm) and flies start emerging from April onwards with maximum population during May to July which coincides with fruit maturity.

Pupa

Eggs

Larvae6-9 day

Adults2-3 months

Egg laying Starts

After 2-3 weeks

Life Cycle of Fruit FlyLife Cycle of Fruit Fly

Eggs1-2 day

Pupa8-10 day

LarvaePupate in soil

Mango Stone Weevil, Mango Stone Weevil, Sternochetus Sternochetus mangiferaemangiferae (Coleoptera: Curculionidae (Coleoptera: Curculionidae))The mango stone weevil The mango stone weevil ((Sternochetus mangiferaeSternochetus mangiferae) is an ) is an important monophagous pest of important monophagous pest of mango, infesting the seed within.mango, infesting the seed within.

Adult weevils become Adult weevils become reproductively active when reproductively active when mango trees come to flower. mango trees come to flower.

The females oviposit on The females oviposit on developing mango fruits. Small developing mango fruits. Small marble-size fruits are preferredmarble-size fruits are preferred..

IdentificationIdentificationAdultAdult - - Adult is dark Adult is dark brown with a short brown with a short snout. weevils are 5 snout. weevils are 5 to 8 mm long.to 8 mm long.

GrubGrub - - A full grown A full grown grub is legless, fleshly grub is legless, fleshly and yellow with dark and yellow with dark head.head.

PupaPupa - Pupation takes - Pupation takes place inside the seedplace inside the seed

SymptomsSymptoms

Grub makes zigzag tunnels in pulp Grub makes zigzag tunnels in pulp

Eats unripe tissue and bore into Eats unripe tissue and bore into cotyledons cotyledons

Fruit dropping at marble stage Fruit dropping at marble stage

oviposition injuries on marble sized oviposition injuries on marble sized fruits. fruits.

Tunnelled cotyledons in mature Tunnelled cotyledons in mature fruit by grubs. fruit by grubs.

Nature of DamageNature of Damage

Larval development and pupation Larval development and pupation occur within the seed. Adults occur within the seed. Adults emerge from the fruits boring emerge from the fruits boring exit holes, damaging the flesh of exit holes, damaging the flesh of ripe fruits. ripe fruits.

Life-cycle is completed in 40 to Life-cycle is completed in 40 to 50 days during June-July. Adults 50 days during June-July. Adults hibernate until the next fruiting hibernate until the next fruiting season. season. There is only one There is only one generation in a year.generation in a year.

Mango Pulp Weevil Mango Pulp Weevil Sternochetus Sternochetus frigidus frigidus (Coleoptera: Curculionidae)(Coleoptera: Curculionidae)

The pest is known to exist in north-east IndiaThe pest is known to exist in north-east India

  Mango pulp weevils look similar to the mango seed Mango pulp weevils look similar to the mango seed weevil already found in some parts of India.weevil already found in some parts of India.

But the pulp weevil attacks the flesh rather than the But the pulp weevil attacks the flesh rather than the seed. seed.

There are no signs of the weevil on the outside of the There are no signs of the weevil on the outside of the fruit. fruit.

The weevils burrow into the pulp of the fruit to feed. The weevils burrow into the pulp of the fruit to feed.

The flesh rots and becomes inedible.The flesh rots and becomes inedible.

IdentificationIdentification

The adult weevil is a dark brown weevil with The adult weevil is a dark brown weevil with paler patches. This small stout weevil has a paler patches. This small stout weevil has a small head and the body covered with papillate small head and the body covered with papillate scales. It is between 6-9 mm in lengthscales. It is between 6-9 mm in length

http://www.daff.gov.au/__data/assets/image/0019/114409/mango_pulp_weevil_1.jpg

SymptomsSymptoms

No outward signs of attack are evident until No outward signs of attack are evident until the adult weevil bores out of the fruit. the adult weevil bores out of the fruit.

To check for infestation, the fruit must be To check for infestation, the fruit must be sliced open. Internal signs of infestation sliced open. Internal signs of infestation include brown tunnels in the flesh and the include brown tunnels in the flesh and the presence of larvae, pupae or adults.presence of larvae, pupae or adults.

Brown tunnels in the flesh

Nature of damageNature of damage

No outward signs of attack are evidentNo outward signs of attack are evident

Life CycleLife Cycle

Eggs are laid on fruit from which larvae develop and Eggs are laid on fruit from which larvae develop and tunnel through the flesh forming a chamber adjacent to tunnel through the flesh forming a chamber adjacent to the seed. the seed.

The larva is plump, pale coloured and legless, with a well The larva is plump, pale coloured and legless, with a well defined head. defined head.

Pupa stays in a chamber hollowed out of the flesh and Pupa stays in a chamber hollowed out of the flesh and develops into an adult. develops into an adult.

The adult weevil stays in the chamber until mature and The adult weevil stays in the chamber until mature and emerges from the fruit by boring a hole through the skin. emerges from the fruit by boring a hole through the skin.

SummarySummary

Mango fruit fly is world’s most serious pest of horticultural crops and in India. There are eight Mango fruit fly is world’s most serious pest of horticultural crops and in India. There are eight species of genus species of genus BactroceraBactrocera which are considered as quarantine pest of mango. The adults are flies which are considered as quarantine pest of mango. The adults are flies with transparent wings while larvae are apodous. Larvae feed upon the pulp of fruit .The emergence with transparent wings while larvae are apodous. Larvae feed upon the pulp of fruit .The emergence of the fruit fly starts from April onwards and maximum population is reached in May-July.of the fruit fly starts from April onwards and maximum population is reached in May-July.

Mango stone weevil is monophagous pest of mango which infests seed (stone) of the fruit. Adults Mango stone weevil is monophagous pest of mango which infests seed (stone) of the fruit. Adults are dark brown, stout and long . Grubs are legless, fleshy, yellow with dark head. Grubs tunnels are dark brown, stout and long . Grubs are legless, fleshy, yellow with dark head. Grubs tunnels through the pulp endocarp and seed coat and destroys it by feeding it. Finally it pupates inside the through the pulp endocarp and seed coat and destroys it by feeding it. Finally it pupates inside the seed. seed.

Mango pulp weevils look similar to the mango seed weevil already found in some parts of India. Mango pulp weevils look similar to the mango seed weevil already found in some parts of India. But the pulp weevil attacks the flesh rather than the seed. There are no signs of the weevil on the But the pulp weevil attacks the flesh rather than the seed. There are no signs of the weevil on the outside of the fruit. The weevils burrow into the pulp of the fruit to feed. The flesh rots and outside of the fruit. The weevils burrow into the pulp of the fruit to feed. The flesh rots and becomes inedible.becomes inedible.

ReferenceReference

Butani, D.K. (1993). Butani, D.K. (1993). Mango: Pest Problems. Delhi, India: Mango: Pest Problems. Delhi, India: Periodical Expert Book Periodical Expert Book Agency, 290 pp.Agency, 290 pp.

Srivastava, R.P. (1997). Srivastava, R.P. (1997). Mango Insect Pest Management Mango Insect Pest Management (first edition). Lucknow, India: (first edition). Lucknow, India: International Book International Book Distributing Co., 272 pp.Distributing Co., 272 pp.

http://www.daff.gov.au/__data/assets/image/http://www.daff.gov.au/__data/assets/image/0019/114409/mango_pulp_weevil_1.jpg0019/114409/mango_pulp_weevil_1.jpg