Domain:         Eukaryota

Kingdom:       Animalia

Phylum:          Arthropoda

Class:               Insecta

Order:              Lepidoptera

Family:            Noctuidae

Genus:             Spodoptera

Species:           S. mauritia

Binomial Name: Spodoptera mauritia

It is widespread from the Red Sea to India, Myanmar, Sri Lanka, Malaya to Australia and widespread in the Pacific Islands, including the Solomons, New Hebrides, Fiji, Samoa, Hawaii, the Society Islands, Austral Islands, Marquesas and the Marshall Islands [2].

পোষক পরিসীমা
The larvae feed on various grasses, including rice, wheat, paddy, Cynodon, Pennisetum clandestinum, Sorghum bicolor, Oryza sativa, and trees such as Casuarina equisetifolia. They are considered one of the major international agricultural pests on crops and pastures [5].

ডিম: Eggs are spherical and creamy in color, which are laid in a group covered over with gray hairs.

লার্ভা: Caterpillars are light green with yellowish white lateral and dorsal stripes in the early stages and later become dark brown or grayish green in color with a crescent shaped black spot on the side of each segment.

পিউপাঃ It pupates in an earthen cocoon in soil. Pupa is dark brown and measures 16-17 mm long.

প্রাপ্তবয়স্কঃ Moth is medium sized, stout built dark brown with a conspicuous triangular black spot on the forewings. Hindwings are brownish white with thin black margins.

1. Rice swarming caterpillar or grass armyworm (Spodoptera mauritia): Mature larvae are 3.8-4 cm long and are green, grey, or brown in colour with dark dull dorsal and sub dorsal longitudinal stripes. Two rows of C-shaped black spots are visible along the backs.

2. Paddy armyworm, true armyworm (Mythimna separata): Mature larvae are 3-4 cm long, green to pink in colour and provided with longitudinal light grey to black stripes running along the entire length of their bodies. Head is brown to orange with an A-marking.

Lawn armyworm caterpillars of their sixth instar do not excrete uric acid, instead they excrete urea as nitrogenous wastes [6]. Spodoptera mauritia has been found in the feces of the Greater tube-nosed bat [7].

The life cycle of this pest is completed in 25 to 40 days with suitable temperature and humidity, through eggs, larvae/caterpillars, pupae and adults. It completes 3-4 generations in a year.

ডিম: A single female generally lays 5-6 oblong egg masses each containing 150-200 eggs at the tips of upright leaves. Eggs are covered with gray hairs/setae. An egg is spherical and creamy in color when laid and acquires a brown tinge as development proceeds.

Larvae: Hatching usually occurs during the morning hours. The newly hatched larvae are very active and feed by scraping the green matter from the leaf tips. The newly hatched/young larvae/caterpillars are light green with yellowish white lateral and dorsal stripes and are about 2 mm in length. As the caterpillars grow, they become grayish brown with a crescent shaped black spot on the side of each segment. When disturbed, larva curls into a ring which is a characteristic common to all cutworms and armyworms.

Pupae: For pupation the mature larvae burrows in the soil to find a suitable place for pupation. Pupation takes place in the soil in an earthen cell slightly below the ground level.

প্রাপ্তবয়স্ক: The adult is stout built, dark brown moth measuring about 15-20 mm in length and 30-40 mm in wing expanse. Forewings of female moths are grayish brown with wavy lines and a dark spot sub centrally. Male moth has immense tufts of hairs on the forelegs. Wings of the male moth are more grayish. The hind wings are brownish white with thin black margins. The moths are nocturnal and hide in the crevices in soils or under vegetation during daytime. The adult moths are strong fliers and move long distances for oviposition.

Plants attacked by caterpillars have skeletonized leaves, shot holes, and dieback stems. Commonly the entire paddy crop dies within a few days due to swarming attacks.

No information found.

Larvae cut the seedlings in large scale Cattle grazed appearance in severely infested fields They feed gregariously and march from field to field

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1. Hand picking and other mechanical methods are used to reduce infection.

2. Flood the nursery to expose the hiding larvae to the surface for birds to pick them up.

3. Allow ducks into the field to feed on the larvae.

4. Larvae perish in heavy rains, and are victims of various diseases, parasitism and predation.

5. Dig trenches around the infested field and place ashes in the trenches to make it difficult for the larvae to escape.

1. Moths traps like wing traps and unitraps can also use to collect adults.[10]

2. Crop rotation in endemic pockets helps

3. Deep plowing the field in summer exposes the larvae and pupae for predation by birds\

4. Remove excess nurseries and weeds from the field and bunds.

5. Flooding the nurseries and paddy fields brings out the larvae to the surface, which get predated by the birds.

6. Herds of ducks, if let into the field, will feed on the caterpillars.

7. Use of bamboo perches facilitates predation by birds.

8. In case of severe infestation, small plots can be isolated and the movement of the caterpillars can be prevented by digging a trench around the infested field wherever possible.

9. Practice of mud plastering of field bunds.

Adults can be eliminated by introducing bolas spiders to the fields. This spider has the ability to spray a pheromone similar to the female moth, to attract male moths.

The nematode Steinernema carpocapsae and usage of viruses like Nucleopolyhedrovirus are also effective [8].

Parasites/parasitoids [9]: Under natural conditions, the egg parasitoids have been found effective in containing the population of S. mauritia. Parasitization of S. mauritia egg masses by Telenomus spp. ranged from 80-90%. A number of larval parasites viz. Apanteles spp., Meterorus spp, Charops bicolour, C. dominans, Charop spp have been reported. A braconid, Apanteles, a solitary internal larval parasite oviposit on the minute first instar caterpillars although it could also parasitize second and third instar larvae.

Predators [9]: The vertebrate predators such as the common crow, the cattle egret, the paddy bird, the white breasted water hen and the mynah, have also been found to predate on the larvae of this pest.

1. Insecticides should be the last resort for armyworm control. In nursery, drain the water and spray chlorpyriphos 20 EC @ 80ml + 20 lit of water for 8 cents.

2. In main field, spary Chlorpyriphos 20% EC @ 500 ml/ac during late evening in case of severe infestation

3. Spray of chlorpyriphos 20 EC @ 2.5 litres/ha or quinalphos 25 EC @2.0 litres/ha or triazophos 40 EC @ 1.0 litres/ha or Dichlorvos 76 SL 600 ml/ha on the paddy crop during evening hours.

4. Dusting of chlorpyriphos 1.5 % D powder controls this pest.

5. Spraying at an early stage is very effective.

6. Deltamethrin was found to be most suitable synthetic pyrethroid and was more effective even at low LC50/LD50 value [10].

তথ্য পাওয়া যায়নি।

তথ্য পাওয়া যায়নি।

No information found.

1. “Spodoptera mauritia, (Boisduval, 1833)”. African Moths. Retrieved 3 August 2016.
2. “Spodoptera mauritia (paddy swarming caterpillar)”. CABI. Retrieved 3 August 2016.
3. Hampson, G. F. (1894). The Fauna of British India, Including Ceylon and Burma: Moths Volume II. Vol. Moths – Vol. II. Taylor and Francis – via Biodiversity Heritage Library.
4. Holloway, Jeremy Daniel. “Spodoptera mauritia Boisduval”. The Moths of Borneo. Retrieved 3 August 2016.
5. “Lawn Armyworm Facts”. Australian Wildlife. Retrieved 3 August 2016.
6. Lazar, KV & Mohamed, UV (1979). “The excretion of urea by the larvae of Spodoptera mauritia Boisd. (Noctuidae: Lepidoptera) during development”. Experientia. 35 (11): 1468. doi:10.1007/bf01962789. PMID 510484. S2CID 36495479.
7. Kemp, James; López-Baucells, Adrià; Rocha, Ricardo; Wangensteen, Owen S.; Andriatafika, Zo; Nair, Abhilash; Cabeza, Mar (1 January 2019). “Bats as potential suppressors of multiple agricultural pests: A case study from Madagascar”. Agriculture, Ecosystems & Environment. 269: 88–96. doi:10.1016/j.agee.2018.09.027. hdl:10138/311518. ISSN 0167-8809. S2CID 92389589. Retrieved 11 June 2022.
8. Herbison-Evans, Don & Crossley, Stella (27 April 2013). “Spodoptera mauritia (Boisduval, 1833) Lawn Armyworm”. Australian Caterpillars and their Butterflies and Moths. Retrieved 23 July 2018.
9. https://ppqs.gov.in/sites/default/files/pop_for_management_of_rice_swarming_caterpiller.pdf
10. https://www.indianjournals.com/ijor.aspx?target=ijor:jer&volume=45&issue=suppl&article=022