Rice Weevil (Sitophilus oryzae)

1. AB 2111 POSTHARVEST BIOLOGY RICE WEEVIL Sitophilus oryzae By W.A.G.E.WIJELATH (AG/12/FT/024) N.H.G.T.MADUSHANI (AG/12/FT/012) Department of Food Science and Technology Faculty of Agriculture University of Peradeniya RICE WEEVIL 1

2. Content Taxonomy Life cycle Morphology Behaviour Habitat Signs of infestation Damages Control RICE WEEVIL 2

3. Taxonomy Kingdom : Animalia Phylum : Arthropoda Class : Insecta Order : Coleoptera Family : Curculionidae Subfamily : Dryophthorinae Genus : Sitophilus Species : S . oryzae RICE WEEVIL 3

4. Life Cycle Consists of four stages Egg stage Larval stage Pupa stage Adult stage RICE WEEVIL 4

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6. Morphology Larvae White to creamy white Legless Humpbacked Fleshy grub Soft RICE WEEVIL 6

7. Pupa White Black, hard head Movable segments Adult 2-3 mm in length Reddish brown to black in colour 4 light yellow or reddish spots on elytra Long, slender snout RICE WEEVIL 7

8. Irregularly shaped pits on thorax Smooth, narrow strip extending down the middle of the back Fully developed wings RICE WEEVIL 8

9. Behaviour I nternal feeders A ctive fliers A ttracted to lights When disturbed, adults pull in their legs, fall to the ground, and feign death RICE WEEVIL 9

10. Habitat Usually found in Grain storage facilities Food processing plants Food markets RICE WEEVIL 10

11. They usually infest Stored rice Wheat Corn Rye Barley Sorghum RICE WEEVIL 11

12. Signs of Infestation H eating at the surface Increased moisture levels Seeds with round holes RICE WEEVIL 12

13. Damages Larvae develop within the seeds consuming the endosperm Adults feed on whole seeds or flour The adult leaves a large, ragged exit hole in the kernel Feeding contributes to heating and infested grain is often damp due to moisture added by the insects’ respiration RICE WEEVIL 13

14. C ontrol Preventing the insects from entering the storage Pest-proof containers Proper bin sanitation before introduction of new grain Cleaning bins regularly Addition of dry ice RICE WEEVIL 14

15. Fumigation Application of insecticide Use of natural repellents Locating and removing all potentially infected food sources Repackaging products in new uninfected packages Freezing infected food below -17.7°C (0°F) for three days Heating to 60°C (140°F) for 15 minutes RICE WEEVIL 15

16. Reference Public Health Vectors and Pests (2013) Rice Weevil [online] Available from: http:// www.kznhealth.gov.za/environ/vector/riceweevil.htm [Accessed on: 05/05/2015] The Pennsylvania State University (2015) Weevils on Stored Grain [online] Available from: http:// ento.psu.edu/extension/factsheets/weevils-on-stored-grain [Accessed on: 05/05/2015] Canadian Grain Commission (2013) Rice weevil [online] Available from: https:// www.grainscanada.gc.ca/storage-entrepose/pip-irp/rw-cr-eng.htm [Accessed on: 05/05/2015] RICE WEEVIL 16

17. Thank You RICE WEEVIL 17