ByDharmendra Singh Lagoriya

BSA-11-410

Introduction• Scientific name: Earias vitella, E. insulana (Noctuidae: Lepidoptera)

Appearance:

Earias vittella : • Eggs are spherical, single and light bluish green colour with

longitudinal ridges. • Caterpillar is brownish white with number of brown and milky

white markings. • Adult moths are medium sized (13-15 mm) with head and thorax

pale brownish white. • Hind wings are silvery-creamy white. • while in fore wings in E. vittella are pale white with a broad wedge

shaped horizontal green band in the middle.

• Earias insulana: • Larva – Brown with dorsum showing a white median longitudinal streak.• Pupa – Brown and boat shaped • Adult -Forewing uniformly silvery green

Distribution and status• Pakistan, India, Sri Lanka, Bangladesh, Myanmar, Indonesia, New

Guinea and Fiji. • More abundant in South India than North India.

Host range• Oligophagus,

• Abelmoschus esculentus (okra)

• Abutilon (Indian mallow)

• Gossypium (cotton)

• Gossypium arboreum (cotton, tree)

• Gossypium hirsutum (American cotton)

• Hibiscus (rosemallows)

• Holly hock and other malvaceous vegetables.

List of symptoms/signs

• Fruit internal feeding• Fruit obvious exit hole• Growing point internal feeding; boring• Inflorescence internal feeding• Leaves wilting• Stems internal feeding

Symptoms of damage

• Affected shoots wither, growing point is killed and side shoots may arise. • Shedding of buds and flowers• Bore hole in fruits and feed• Damaged buds and flowers fall while affected fruits are Deformed. • Affected fruit is unfit for consumption. • Affected fruit show entry hole plugged with excreta. • Bored fruits lose their market value.

Description of damage symptoms • Larva bores into tender terminal shoots in the vegetative stage and

flower buds, flowers and young fruits in the fruit formation stage. • The damaged shoots droop, wither and dry up. • The infested fruits present a deformed appearance and become unfit

for consumption. • Bore holes plugged with excreta.

Cont….• Infestation generally starts with shoot boring in the young crop. • E. vittella enters the terminal bud of the vegetative shoot and channels

downward from the growing point, or directly penetrates the internode.• Mostly soft growing tissue is attacked. • Extensive tunneling will result in the wilting of the top leaves and the

collapse of the apex of the main stem. • If only the apical bud is attacked, damage may not be noticed until the

main stem divides ('twinning') as the axillary buds take over.• Attack moves to buds and flowers as they appear, which wither and are

shed.

• There is usually a conspicuous hole the shedding of minute buds, often blamed on midribs, might be due to very young Earias larvae.

• The tendency for secondary invasion by fungi and bacteria may conceal the infestation.

• The attack of okra follows a similar pattern to that of cotton. • Terminal shoots are bored initially, with attack moving to flower buds

and fruit as they appear. • Severe attack causes the shedding of flower buds and reduced yield.• When attacking the fruit, the larvae feed on the milky seeds and other

contents of the capsule , leaving excrement filled tunnels.

Cont………

Life cycle

• Egg period: 3-4 days. • 385-400 eggs / female. • Spherical, light bluish, green, crown shaped, laid singly on shoot tips,

buds, flowers and fruits. • Larva: 10-17 days. • Six instars.: Pupa: 6-10 days. • Pupates in an inverted boat shaped cocoon.• completing life cycle 20-25 days.

Earias vitella Earisa insulana

Management

•Cultural:• Grow resistant cultivars like AE 57, PMS 8, Parkins Long

green, PKX 9275, Karnual Special.• Pusa Swani is highly susceptible.• Collect and destroy infested shoots, buds, flowers and

fruits.• Remove the alternate hosts like Hibiscus cannabinus, H.

abelmoschus and Abutilon indicum in the cropped area.

Physical

• Set up light traps to monitor the moths and their egg laying @ 12/ha

• Set up sex pheromone traps @ 5/acre. The peak activity is noticed during November – January

Biological• Release egg parasitoid Trichogramma

chilonis @40,000/acre three time and egg- larval parasitoid Chelonus blackburnii can also released .

• Release first instar larvae of green lacewing Chrysoperla carnea @ 10,000/ha.

• Spray Bacillus thuringiensis (B.t )formulation such as dipel @ 2 g / lit.

Chemical