2.4 Maize Weevil, Sitophilus zeamais (Coleoptera: Curculionidae) ... 4.8 Damage assessment of the methanol extracts of botanicals by Prostephanus truncatus and Sitophilus zeamais. Avoid sowing new ground with maize after pasture in areas that have a known history of white grubs. Maize weevil, Sitophilus zeamais; adult side view. Maize weevil, Sitophilus zeamais Motschulsky, is a Heat damaged maize kernels may have a discolored, wrinkled, and blistered, be puffed and/or swollen, or their seed coats may be peeling off Heat damage most likely comes from drying of grain. well as F. moniliforme and P. islandicum and others. materials and broken kernels. Relationship among aspergillus flavus infection, maize weevil damage, and ear moisture loss in exotic x adapted maize. It is difficult to detect the weevil unless populations are high as it spends most of its life inside grain. The grain damage was significantly different (P≤0.01) among the tested varieties at 30 days after observations in no-choice condition (Table 3).After 30 days of treatment the highest loss was recorded on Mankamana-3 whereas the lowest loss was recorded on Arun-2, Arun-4, and Rampur composite, respectively. Infestations can start in the field, but most damage occurs in storage. Commonly, loss of weight is up to 5%, but severe infestations increase the losses up to 40%. Her Majesty's Stationery Office. Household insecticides have no effect on insects within food Treatment of grains for human consumption or for animal feed [make sure the product is labelled for use on rice, maize and small grains (barley, oats, wheat)]. Spray the bins about four to six weeks prior to storing grain. Phosphine: Used as a fumigant; grain is covered by a tarpaulin or in other ways sealed for the duration of the fumigation. Maize weevil is among pests of storage sorghum in Ethiopia (Temesgen and Waktole, 2013). Android Edition Note care must be taken to ensure that the treated seed does not contaminate that used for human consumption. floor and wall surfaces both inside and outside the bin should be It is a subset of damage including broken or cracked kernels but is identified as its own type of damage by the USDA. Their larvae hatch from eggs laid on to grains by weevils. http://keys.lucidcentral.org/keys/v3/eafrinet/maize_pests/key/maize_pests/Media/Html/Sitophilus_zeamais_Motschulsky_1855_-_Maize_Weevil.htm. If using bins, remove any grains that remain (and, if possible, spray with insecticide). This weevil is a cosmopolitan pest of grain, preferring whole grain            This species attacks both standing crops and stored cereal products, including wheat, rice, sorghum, oats, barley, rye, buckwheat, peas, and cottonseed. AUTHOR Grahame Jackson1Information from Swaine G (1971) Agricultural Zoology in Fiji. There are many pantry pests which can infest homes and businesses. For extra protection, some treat seeds or grains before Look for the characteristic large emergence holes in the grain with irregular edges. maize weevil damage. for garbage removal, or bury deep in the soil. Approximately, 500 g of Maize Kernels in glass jars were moisture equilibrated in an incubator for a period of one week before infesting with 300 unsexed weevils (Miller et al.,; 1969). Photos 1,2&4 Walker K (2006) rice weevil (Sitophilus zeamais) PaDIL - http://www.padil.gov.au. If there is an infestation, locate it by putting sticky traps around the room or warehouse where it occurred. minimum of thirty days is required for passing through the egg, larval decrease germination and baking quality of flour. For small infestations, freezing for several days and then heating for 24 hours is affective. There is a withholding period of 1 day before treated grain can be used for human or stock consumption. They frequently cause almost complete destruction of grain in elevators or bins, where conditions are favorable and the grain is undisturbed for some length of time. The only way to control these pests is fumigation. Heating grain to 60C can kill larvae; however, this may The female has a … Description. The eggs hatch into white, legless larvae, which remain inside the grain, and pupate there. Moisture levels should be about 12% (most stored product pests required moisture levels of 13-18% to reproduce). Worldwide. NIH 5. is an important pest of maize that attacks the grain both in the field and during storage. Damage by S. zeamais causes food loss, … Insecticides are supplementary to sanitation and proper Other insect species develop on the cracked or bro-ken kernels and grain dust, which can be produced by … Development is about 35 days under optimal cnmditions. Infestation by this weevil begins in the field, but significant damage happens during storage (Girma. After the bin is cleaned, and all needed repairs have been made, the treated. is an important pest of maize that attacks the grain both in the field and during storage. It varies from dull Other pests Sucking pests. Note that many storage pests are resistant to malathion. By November 12, 2020 Uncategorized 0 comments Tainting with white, dusty excreta which contaminate the product as well as rendering it unpalatable. Maize is the is also shorter comparatively (Raina, 1970). If infestation occurs in Mating often occurs within 24 hours of adult emergence from grain kernels. S. oryzae is universally regarded as one of the most destructive primary pests of stored cereals. It is recorded from Australia, Fiji1, New Caledonia, Papua New Guinea, Solomon Islands, and Tonga. infested foods in wrapped, heavy plastic bags or in sealed containers Maize weevil, Sitophilus zeamais; another view of the four (very) faint, reddish spots at the corner of the wing case. Use a flashlight or The use of insecticides is discouraged around food ), the red and confused flour beetles (Tribolium spp. The weevils occur during and after harvest and are most common in storage. Secondary damage is caused by moulds, insects and mites. Maize, rice, sorghum, wheat, casssava and yam, and also dried stored products, including pasta. Maize Weevils . weevil, but larger Accessed 26 September 2007. In Tanzania, the maize weevil Sitophilus zeamais Motshulsky causes significant damage, although new studies showed that some maize varieties are more resistant to attack (Rugumamu, 2012). After the grain intervals during cooler months for the presence of hotspots, moldy Various neem products were compared with copra oil, palm oil and 0.25% diazinon dust for protection of stored maize against the grain weevil, Sitophilus zeamais Motsch. In order to obtain test insects of known or similar age, these weevils were … Of the three, the rice weevil is probably the most insidious, owing largely to the ability of flight. Look for a dull red-brown to nearly black weevil, with faint yellowish or reddish spots on its back, at the corners of the wing cases (Photos 3&4). averaging about three thirty-second inch in length. Treatments can be 338). Cereal Research Communications. In many instances, Both insects are less coldhardy than the Grain weevil and will not normally overwinter in unheated premises or grain stored at normal temperatures. Bt: Some success has been reported using Bt. Maize weevil, greater grain weevil, greater rice weevil. Epub 2016 Nov 3. The maize weevil Sitophilus zeamais Motsch. Primary pest; grain feeder Order: Coleoptera Family: Curculionidae Acronym: SZE. Before storage: CHEMICAL CONTROLIf pesticides are needed, use the following:Routine hygiene treatments. knowledge needed for their proper use, a qualified pesticide applicator Malathion: apply to walls, floors, and inside of bins used to store the grain. The mobile application is available from the Google Play Store and Apple iTunes. Both are internal feeders, which means the larva develops inside whole grain kernels. Pyrethrins: Used as a grain protectant (sometimes with piperonyl butoxide). Maize weevil, Sitophilus zeamais, clearly showing four light reddish to yellowish spots at the corners of the wing case. Asia, Africa, North, South and Central America, the Caribbean, Europe, Oceania. Key words : Genetic resistance, stored grain pest, QPM corn It is a pest of stored maize, dried cassava, yam, common sorghum and wheat. The reddish markings on the wing covers are more clearly defined. Thereafter, weevil damage was heavy in infested plots and negligible in controls. They have densely spaced pits on the pronotum that are round (maize weevil) or elongated (rice weevil). An egg Overall, control is similar to that recommended for the rice weevil (see Fact Sheet no. IMPORTANCE AS A PEST: Grain weevils are important pests of farm-stored grain. CABI says that "Sitophilus zeamais is predominantly found associated with maize grain, whereas Sitophilus oryzae is associated with wheat". The rate of development Photo 1. The grub changes to a naked READ THE INSTRUCTIONS. and pupal stages. ples of internal feeders include maize weevil, rice weevil, granary weevil, lesser grain borer, bean weevil, cowpea weevil, and larvae of Angoumois grain moth. insects from entering the grain on the surface. Photo 3. The two species look almost identical without magnification. However, its coloring is generally darker than that of the rice weevil. This fact sheet is a part of the app Pacific Pests and Pathogens. Prevention is the best strategy; but if resistance is Collect and dispose of spilled grain in or around the storage area. control operator who has the training, experience, equipment, and rice weevil is probably the most insidious, owing largely to the. Photo 2. The most serious insect pests attacking stored maize are the maize and granary weevils (Sitophilus spp. Long thought to be simply a larger strain of rice weevil, the maize weevil looks very similar. If the problem It is slightly larger, up to 1/8-inch long, and like the rice weevil, it is dull reddish brown to black with four red-yellow spots on its back. If you detect an Photo 4. Population abundance and growth physiology of the maize borer (Ostrinia furnacalis)and the maize weevil (Sitophilus zeamais)were investigated during maize growing season and grain storage period, respectively, to assess insect pests’ occurrence and economic damage. Maize leafhoppers and maize thrips are widespread but irregular in Queensland, and can rapidly re-infest crops after spraying meaning more than one spray may be required. materials. CULTURAL CONTROLIt is most important to dry the grain properly, to keep the storage area clean, and to monitor the grain often and regularly. pitted with somewhat irregularly shaped punctures, except for a smooth feeds on the interior of the grain kernel. The larvae cause damage by boring into the grain, making holes and grinding it to a fine powder. Take special care to treat all cracks, crevices, and areas Weevils were shown to carry significant A. flavus contamination, as lack of. Look for the adults, with long snouts (about 1 mm). Grain that is to be stored for longer than six months may need a Infestations can start in the field, but most damage occurs in storage. Insect resistant maize: recent advances and utilization. The maize weevil (Sitophilus zeamais) adult. becomes severe and widespread, contact a reputable, licensed pest A very destructive weevil, with the adults attacking sound grain, and the adults and the larvae feeding inside them, leaving large cavities and emergence holes. In contrast, his treated samples revealed an average of only 36 maize weevils/500g maize grain, just 11% of the average weevil numbers in the untreated samples. Pyrethrins are manufactured from chrysanthemum flowers. Keep grain storage rooms, sheds, houses, or "cribs" clean. The maize weevil has fully developed wings, and is a stronger flyer than the rice weevil, Sitophilus oryzae, and spreads more widely this way. metering device calibrated to apply the proper amounts. Motschulsky (Coleoptera:Curculionidae) is an important pest of maize in storage in term of losses caused in food quality and quantity in Nepal. 328). Storing maize on the cob with husks on re­duces weevil infestation. From the suspected, first eliminate other possible causes. carefully. Proceedings of an International Symposium held at the International Maize and Wheat Improvement Center, 27 November-3 December 1994., 91-95; [11 ref]. wings beneath its wing covers and can fly readily. 32:371-378. Most eggs are laid in the first 4-5 weeks of the female's life which lasts about a year. source of infestation and quickly get rid of it. The first study found 100% maize weevil mortality for hermetically sealed containers and the oxygen levels inside them declined from 21% to between 3 and 10%. Note that identification of Sitophilus zeamais is difficult because of its similarity with Sitophilus oryzae, and needs to be done by a taxonomist. should be contacted to perform the fumigation. areas, and live insects. The Maize weevil will breed on maize in the field, but the Rice weevil only breeds in stored grain. Similar cautions apply as for pyrethroids (above). A cosmopolitan pest of stored products (Longstaff 1981), and prior to the Usually, the greater the number of weevils the nearer the source. Of the three, the Maize weevils (known as Sumpwa sumpwa in Nyanja language) cause large losses in maize grains. If using sacks, do not reuse those that stored previous harvests. Photo 2  Georg Goergen, IITA-Benin. Because of the high toxicity of registered fumigants and technical To kill the internal stages (larval and pupal), you Maize Weevils are small and easy to kill, but they can complete their life cycle quickly. The visible damage to the trial’s stored maize grain was also far more evident in the untreated samples, averaging 68%, compared with 14% damage in the treated samples. The maize weevil has fully developed wings, and is a stronger flyer than the rice weevil, Sitophilus oryzae, and spreads more widely this way. Both adults and larvaefeed on internally on maize grains and an infestation can start in the field (when the cob is still on the plant) but most damage occurs in storage. Maize weevil, Sitophilus zeamais; adult, view from above. It can be found in numerous tropical areas around the world, and in the United States, and is a major pest of maize. 3.1.3. Alcidodes is largely a pest of African crops but far greater losses are caused by various widely distributed species of grain weevil, Sitophilus. necessarily more susceptible to maize weevil damage than it is the normal endosperm type of the commercial corn available on the market. other light source to examine all food storage areas and food products light reddish or yellowish spots. Grain placed in a clean bin should be must fumigate. Maize weevils carried a great collection of other fungi including A. niger, A. glaucus, A. candidus, Penicillium islandicum, P. citrinum, Paecilomyces, Acremonium, Epicoccum, F. semitectum, yeasts and many others. red-brown to nearly black and is usually marked on the back with four It must not be used for animal consumption, poultry feed or mixed with animal feed. infestation early, disposal alone may solve the problem. The maize weevil is very similar to the rice weevil, Sitophilus oryzae (see Fact Sheet no. packages. Mechanisms of resistance in maize grain to the maize weevil and the larger grain borer. Before grain is placed in a bin, it should be screened to eliminate fine Dry the grain as soon as possible after harvest, and re-dry during storage if necessary. Damage of Maize Weevil on Maize Varieties on Weight Basis. Wheat, corn, m… protective application of an approved insecticide. If any of these conditions exist, the grain Identification of host kairomones from maize, Zea mays, for the maize weevil, Sitophilus zeamais. Rice weevils and maize weevils are about 1/8 inch long and brown. These weevils are very destructive grain pests. Synthetic pyrethroids: e.g., deltamethrin or cypermethrin. hatches in a few days into a soft, white, legless, fleshly grub which et al., 2008; Baidool et al., 2010). is slightly slower for the maize weevil than for the rice weevil. Produced with support from the Australian Centre for International Agricultural Research under project PC/2010/090: Strengthening integrated crop management research in the Pacific Islands in support of sustainable intensification of high-value crop production, implemented by the University of Queensland and the Secretariat of the Pacific Community. Though Meal Moths, Grain Beetles and Flour Beetles are very common, Maize Weevils are just as likely to be the unwanted insect in such areas. Exposed adults. The maize weevil is found in all warm and tropical parts of the world. If practical and regulations allow, dispose of heavily Sieving has been used as a method of removing adult weevils, but it is very labour intensive. storage with dusts or sprays of synergized pyrethrins, labelled for this Females lay up to 150 eggs placed in holes chewed into the grain and plugged with a gelatinous substance. insecticides to get the control job accomplished safely. Development is about 35 days under optimal cnmditions. In sub-tropical and tropical countries. These weevils are very destructive grain pests. Key pests: Almond moth, angoumois grain moth, confused flour beetle, flat grain beetle, granary weevil*, Indian meal moth, lesser grain borer, maize weevil*, red flour beetle*, rice moth, rice weevil*, rusty grain beetle*, sawtoothed grain beetle* *Suppressed to low levels (Please see label for complete list of pests.) The end of the body of the maize weevil is more rounded than that of the LGB. The maize weevil has fully developed Malathion: i) as a spray; treat grain and do not use for food within 90 days of treatment; ii) as a dust; treat grain and do not use for food within 14 days of treatment. Neem. Remove old kernels, and sweep floors, walls, doors, and vents to collect seeds, grain powder and dust, and burn them before storing the new harvest. Adults are 3-4 mm long, reddish-brown to black (Photos 1&2), with four light reddish to yellowish spots at the corners of the wing cases (Photo 3&4). around doorways and other places where insects could hide or enter. Weevil migration and reproduction in control plots reduced treatment differences in damage during the first 3 yr. The thorax is densely The maize weevil, known in the United States as the greater rice weevil, is a species of beetle in the family Curculionidae. ), Angoumois grain moths (Sitotroga cerealella), and the larger grain borer (Prostephanus truncatus). Perhaps a method to avoid if seed is for growing. The eggs hatch into larvae, which eat the plant material surrounding them. Maize kernels treated with neem oil or ash were damaged less than the control. Apple iOS Edition. (Follow label directions and safety precautions.) Note, toys can sometimes be filled with grain and act as a source of infestation; so too can dried flowers. ALWAYS CHECK WHETHER THE PRODUCT IS FOR TREATING EQUIPMENT, BINS AND BUILDINGS OR FOR TREATING GRAIN FOR HUMAN USE AND ANIMAL FEED. use. Prior to storage, maize can be treated with Actellic 25 EC (20 % solution) by spraying the insecticide with a spraygun. narrow strip extending down the middle of the dorsal (top) side. Corrêa AS, Vinson CC, Braga LS, Guedes RN, de Oliveira LO. The simplest and most effective measure is to locate the Attempt made to review bionomics and management practices of this pest gleaning published literatures/papers on national and international journals, proceedings, reports, newsletter and books. 1/8- to 3/16-inch long .The maize weevil is similar to the rice Neonicotinoids: e.g., imidocloprid. Interpretive Summary: Natural sources of resistance to diseases and insects of corn are very valuable in corn production. Locate the source and destroy it by wrapping the foods in heavy plastic bags or in sealed containers, and burn or bury deeply in the soil. The maize weevil is a small snout beetle which varies in size, storage on maize weevil mortality, and effect of storage containers physical disturbance on maize weevil mortality. checked at two week intervals during warm months and at one month Infested grain will usually be found heating at the surface, and it may be damp, sometimes to such an extent that sprouting occurs. All three weevils develop as larvae within the grain kernels. to flour or meal. For small amounts, store maize, rice, wheat, etc., in plastic containers. Maize weevils, or referred to in the United States as greater rice weevils, are a species of beetle bearing its name from its status as a larger relation of the rice weevil.They are found in many areas around the world, mainly tropical, but are considered a pest in the United States. Type of damage: These weevils are very destructive grain pests. Since it is an internal pest, residual control will only kill. applied as the grain is loaded into the bin through the use of a It is possible to confuse the maize weevil with other storage insect pests such as the larger grain borer - LGB (Prostephanus truncatus). During large infestations, heat and moisture are produced, leading to colonisation by moulds and mites. Low moisture content (10 % or less) and low tempera­tures (below 15 °C) will prevent weevil development. These are smaller and less conspicuous than Alcidodes but they do more damage because they lay their eggs in the fruits or seeds of beans, maize or rice as the crops are growing in the field. spite of these precautions, fumigation of the grain will be necessary. Doorways and other places where insects could hide or enter maize grains this may decrease germination and baking of... Insects are less coldhardy than the control, including pasta weevil ( Sitophilus zeamais Nyanja language cause! 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And reproduction in control plots reduced treatment differences in damage during the first 3 yr weevil ( Sitophilus.! Author Grahame Jackson1Information from Swaine G ( 1971 ) Agricultural Zoology in Fiji ; if. Human or stock consumption Tribolium spp or cracked kernels but is identified as its type... Its wing covers are more clearly defined 4-5 weeks of the LGB life grain! Hours is affective dusty excreta which contaminate the product as well as rendering it.! And low tempera­tures ( below 15 °C ) will prevent weevil development of African crops but greater. The grub changes to a fine powder grain for human or stock consumption varies in size, averaging about thirty-second! Or around the room or warehouse where it occurred of beetle in field..., leading to colonisation by moulds and mites the three, the rice weevil Sitophilus... Check WHETHER the product as well as F. moniliforme and P. islandicum and others is. Damage, and needs to be simply a larger strain of rice weevil ) may a... Inside whole grain kernels rice, sorghum, wheat, etc., in plastic containers storage areas and food carefully! Rice, wheat, etc., in plastic containers available from the the insidious. Doorways and other places where insects could hide or enter the app Pacific pests and.... By weevils emergence from grain kernels: Routine hygiene treatments insects are less coldhardy than the control in or the! Or grain stored at normal temperatures side view severe infestations increase the losses up to 40 % effect on within! To eliminate fine materials and broken kernels small and easy to kill the stages! Occur during and after harvest, and inside of bins used to store the grain in. Long snouts ( about 1 mm ) human use and animal feed will breed on in! Note, toys can sometimes be filled with grain and plugged with gelatinous!, a surface dressing can be used for human use and animal feed size, averaging three... Minimum of thirty days is required for passing through the egg, larval and pupal stages or enter or. Ensure that the treated seed does not contaminate that used for human stock... Within food packages, whereas Sitophilus oryzae is associated with wheat '' 25 EC 20... For growing from infestations for several months special care to treat all,..., view from above simplest and most effective measure is to locate the source infestation! Cabi says that `` Sitophilus zeamais, clearly showing four light reddish to yellowish spots the... The treated seed does not contaminate that used for human or stock consumption weevils occur during after... Mm ) many pantry pests which can infest homes and businesses fully wings! To walls, floors, and also dried stored products, including pasta has! Internal stages ( larval and pupal stages product as well as rendering it unpalatable and stages... 5 %, but the rice weevil take special care to treat all cracks, crevices, and re-dry storage... Aerated to lower the moisture level and temperature, store maize,,! Identification of host kairomones from maize, rice, sorghum, wheat, maize weevil damage in! Overwinter in unheated premises or grain stored at normal temperatures Sitophilus spp exotic x maize! Occurs in storage, residual control will only kill dried stored products, including.. Thought to be done by a taxonomist cautions apply as for pyrethroids ( above ) and during... Weevil has fully developed wings beneath its wing covers are more clearly defined should be 12...