Fall Armyworm (Spodoptera frugiperda) is a nocturnal pest native to the Americas that primarily damages maize crops. It was first detected in Africa in 2016 and has since spread to over 40 African countries and 12 major maize producing nations. Fall Armyworm was first recorded in Nepal in 2019 and has since infested over 64 districts. It can survive year-round in certain districts. The pest feeds on over 80 plant species, especially cereals, and causes damage through its caterpillar stage by consuming foliage. Management strategies include cultural practices, biological controls using Bt, host plant resistance, and applying safe insecticides as a last resort.

1. Fall Armyworm
(Spodoptera frugiperda)
Lepidoptera, Noctuidae
Avin Kharel
IAAS, Lamjung Campus (TU)
(aveenkharel005@gmail.com)

2. INTRODUCTION
• Nocturnal habitat insect of mainly maize crop belonging
to Lepidoptera order.
• Larva of fall army worm directly damage to other crops
beside maize
• Native insect of American continent.
• First time outbreak in African continent(Nigeria) in 2016,
January
• Spread in more than 40 countries of the Africa.
• Affect 12 maize producing countries of Africa,(affect 4
crore population and decline maize yield by 73%)

3. • First time recorded in Nepal in 2076 (Baisakh 26) in
Nawalparasi Gaindakot.
• Route (America Africa India Nepal)
• Economic loss of about 6.19 Arab US dollar

4. DISPERSION OF FAW IN NEPAL
• Reaches to all maize growing areas in Nepal
• Infest more than 64 districts of Nepal (research)
• Survive year round in Chitwan and similar districts
(NMRP)
• Favorable environment for growth and development
in terai and inner terai of Nepal (CABI)
• More favorable environment of FAW in eastern Nepal
than western Nepal

5. INFECTED CROPS
• Mostly damage on cereal crops
• Feeds on more than 80 species
• Mainly crops damage by FAW includes maize and instead
of it damage on rice, wheat, sugarcane, sugarbeet,
cabbage, sorghum, groundnut, soyabean, onion, cotton,
tomato, potato etc.

6. WHY FAW IS MORE HARMFUL?
• Adult of lifetime of about 14-21 days lay eggs about 1500-
2000
• Feed on more than 80 species of crop
• Make a flight up to 100 Km at night for searching food and
shelter
• Lay eggs and produce the progeny throughout the year if
it found food regularly

7. IDENTIFICATION
FROM EGGS
• Dome shaped eggs (flattened base and curved upward)
• Egg measures 0.4mm in diameter and 0.3mm height
• Number of egg per mass varies (100-200)
• Total egg production per female average about 1500 with
maximum of over 2000
• Eggs deposited sometimes in layers, but most eggs spread
over a single layer attached to foliage
• Duration of egg is only 2-3 days during summer

8. Eggs of Fall Army Worm

9. IDENTIFICATION
FROM LARVA
• Usually six instars
• Attain length of about 1.7-34.2 mm
• Larva may be green dorsally
• Young larva are greenish with black head, head turning orange
color in second instar
• Inverted “Y” in head (whitish line)
• Four blackish spots (rectangular)in upper 8th end segment
• Duration of larva is 14 days in summer and 30 days in cool
climate.
• 3 longitudinal parallel yellow lines from posterior part of head
to end of abdomen

10. Larva of
Fall Army
Worm

11. IDENTIFICATION
FROM PUPAE
• Normally takes place in soil (2-8 cm depth)
• Larva construct cocoon, oval in shape, 20-30 mm length
• Pupa is reddish brown in color
• Measures 14 to 18 mm length and 4.5 mm width
• Duration is 8 to 9 days in summer and 20 to 30 days in
winter

12. Pupa of
Fall Army
Worm

13. IDENTIFICATION
FROM ADULT
• Moth have a wingspan of 32 to 40 mm
• Male: gray and brown forewings, triangular white spot at tip and
near center of wing
• Female: Less distinctly marked forewings, grayish brown to fine
mottling of gray and brown
• Hindwings are iridescent silver white with a narrow dark border
in both sexes
• Adults are nocturnal, active during warm humid evenings
• Duration is average of about 10 days with a range of about 7-21
days

14. Adult of
Fall Army
Worm

15. LIFE CYCLE OF FALL ARMY WORM

16. NATURE OF DAMAGE
• Larvae cause damage by consuming foliage
• Young larvae initially consume leaf tissues from one side,
leaving the opposite epidermal layer intact
• By the second or third instar, larva begin to make holes in
the leaves and eat from the edge of the leaves inward
• Older leaves cause extensive defoliation
• FAW will feed by burrowing through the husk on the side
of the ear

18. MANAGEMENT
• Collection of moth population by using black light trap and
pheromone traps
• Cultural techniques: Early planting and early maturing
varieties
• Improvement of cultivation practices
• Biological Control: Use of Bt (Bacillus thuringiensis)
• Host plant resistance
• Collection and destruction of egg masses

19. MANAGEMENT
• Use of natural birds
• Use of botanical products
• Seed treatment (Imidacloprid 48%FS)
• Selection of resistance or tolerance genotype
• Push Pull Strategy: Desmodium at intercrop and Napier at
periphery of maize crops
• Use of natural enemies like Ladybird beetle, spider,
Trichogramma spp
• For the ultimate source, spray safe insecticides like
Spinosad 45% SC, Azadiractin, Emamectin benzoate 5%SG

20. THANK YOU