Scirtothrips dorsalis Hood.
Taxonomic position: Insecta, Hemimetabola, Thysanoptera, Terebrantia, Thripidae.
A Ribosomal DNA ITS2 marker for the identification of S. dorsalis is available.
Common name: Chilli thrips, yellow tea thrips.
Geographical distribution: The Far East, Oceania, South Africa, Israel, the Caribbean and southern USA. Distribution Maps of Plant Pests, Map 475. CABI/EPPO, 2010.
Host plants: This is a polyphagous species, having been found on over 120 plant species.
Morphology: The body of the adult is 1-1.2 mm long, initially white then turning yellowish, with dorsal dark spots on the abdomen and red eyes. Forewings greyish. The larvae are pale-white.
Life history: The eggs (40-60/female) are laid in the youngest plant tissues, on which the larvae feed. A generation can be raised at 26°C in about 3 weeks, the calculated threshold of development being at 10°C, and about 280 day degrees are required for on generation. The pest pupates in curled leaves or in the calyx of flowers and fruits. The adult is most active in the early afternoon.
Economic importance: Scirtothrips dorsalis is a major pest of vegetable crops (especially chilli pepper), banana, cotton, citrus, mango and other fruit and ornamentals in eastern Asia, Africa, and Oceania. It infests all above-ground host parts, preferring young leaves, buds and fruits, and its feeding results in damaging scars, leaf distortions, bronzing and defoliation. Heavily attacked plants are stunted or dwarfed. In addition, this thrips is capable of spreading several peanut and tobacco virus diseases. Reported damage came to 25-55% of the chilli yield in India, and is considered one of the key pests of mango in south-east Asia.
In Israel this species has been collected off avocado, citrus, mango and other commercial crops, apparently without, so far, causing any damage.
Management
Monitoring: Yellow sticky traps and differently-colored plastic cup traps (CC traps) were used for monitoring. The small size of the pest requires careful searches within host buds and flowers.
Plant resistance: A few chilli accessions in India appear to be resistance to the thrips.
Chemical control: The use of many pesticides provides only inconsistent control, but spinosad and imidacloprid resulted in about 90% pest control. Similar results wereobtained with buprofezin, a chitin synthetase inhibitor.
Biological control: Several predatory Thysanoptera attack S. dorsalis in the Far East, but their effect on the pest populations is unclear. The anthocorid Orius insidiosus Say controlled the pest on peppers. The parasitoid Megaphragma sp. (Trichogrammatidae killed about 50% of the pest’s eggs in Japan. The commercially-available phytoseiid Amblyseius swirskii Athias-Henriot (known in the trade as the Swirskii mite) controlled the pest on pepper plants, and Euseius sojaensis (Ehara) on vinegrapes. The entomopathogenic fungus Fusarium semitectum Berk. and Rav reduced thrips populations in India.
References
Arthurs, S. (and 6 co-authors). 2009. Evaluation of Neoseiulus cucumeris and Amblyseius swirskii (Acari: Phytoseiidae) as biological control agents of chilli thrips, Scirtothrips dorsalis (Thysanoptera: Thripidae) on pepper. Biological Control 49: 91–96.
Babu, B.S., Pandravada, S.R., Reddy, K.J., Varaprasad, K.S. and Sreekanth, M. 2002. Field screening of pepper germplasm for sources of resistance against leaf curl caused by thrips (Scirtothrips dorsalis Hood) and mites (Polyphagotarsonemus latus Banks). Indian Journal of Plant Protection 30: 7-12.
Chu, C.C., Ciomperlik, M.A., Chiang, N-T., Richards, M. and Henneberry, T.J. 2006. Developing and evaluating traps for monitoring Scirtothrips dorsalis (Thysanoptera: Thripidae). Florida Entomologist 89: 147–55.
Doğramaci, M., Arthurs, S.P., Chen, J., McKenzie, C., Irrizary, F. and Osborne, L. 2011. Management of chilli thrips Scirtothrips dorsalis (Thysanoptera: Thripidae) on peppers by Amblyseius swirskii (Acari: Phytoseiidae) and Orius insidiosus (Hemiptera: Anthocoridae). Biological Control 59: 340–347.
Farris, R.E., Ruiz-Arce, R., Ciomperlik, M., Vasquez, J.D. and R DeLeón, R. 2010. Development of a ribosomal DNA ITS2 marker for the identification of the thrips, Scirtothrips dorsalis. Journal of Insect Science 10: 1-15.
Kumar, V., Kakkar, G., McKenzie, C.L., Seal, D.R. and Osborne, L.S. 2013. An overview of chilli thrips, Scirtothrips dorsalis (Thysanoptera: Thripidae) biology, distribution and management. Chapter 3 in: Soloneski, S. and Larramendy, M. (eds), Weed and Pest Control - Conventional and New Challenges, Intech Publishers, pp. 53-77.
Mikunthan, G. and Manjunatha, M. 2008. Impact of habitat manipulation on mycopathogen, Fusarium semitectum to control Scirtothrips dorsalis and Polyphagotarsonemus latus of chilli. BioControl 53: 403-412.
Seal, D.R., Klassen, W. and. Kumar, V. 2010. Biological Parameters of Scirtothrips dorsalis (Thysanoptera: Thripidae) on selected hosts. Environmental Entomology 39: 1389-1398.
Shibao, M., Ehara, S., Hosomi, A. and Tanaka, H. 2004. Seasonal fluctuation in population density of phytoseiid mites and the yellow tea thrips, Scirtothrips dorsalis Hood (Thysanoptera: Thripidae) on grape, and predation of the thrips by Euseius sojaensis (Ehara) (Acari: Phytoseiidae). Japanese Journal of Applied Entomology and Zoology 39: 727-730.
Shibao, M.; Hosomi, A.; Tanaka, H. 2010. Seasonal fluctuation in percentage parasitism of the yellow tea thrips, Scirtothrips dorsalis Hood (Thysanoptera: Thripidae) by an egg parasitoid of Megaphragma (Hymenoptera: Trichogrammatidae) on grapes. Japanese Journal of Applied Entomology and Zoology 54: 115-126.
Sontakke, B.K. and Mohapatra, L.N. 2014. Bioefficacy of buprofezin 25 SC against Scirtothrips dorsalis (Hood) and yellow mite, Polyphagotarsonemus latus (Banks) infesting chilli. Indian Journal of Entomology 76; 177-180.
zur Strassen, R. and Kuslitzky, W. 2011-2012. An annotated checklist of the thrips of Israel (Thysanoptera). Israel Journal of Entomology 41-42: 53–77.
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