They have densely spaced pits on the pronotum that are round (maize weevil) or elongated (rice weevil). Weevils can be found infesting a variety of grain and food materials. The maize weevil also infests other types of stored, processed cereal products such as pasta, cassava, and various … The number of eggs is dependent on food, season, or temperature. Eggs, larval and pupal stages are all found within tunnels and chambers bored in the grain and are thus not normally seen. Bean weevils also do not possess the telltale jutting snout present on true weevil species. All three species attack grain and grain products, but they are primarily pests of whole grain in storage. Gardeners with vine weevil should keep up their guard because stopping control measures after the apparent disappearance of the weevil can allow numbers to build up again. It is black-brown in coloring although it can be red-brown shortly after adult emergence. Adults emerge from the grain and can be seen walking over the grain surfaces. They cannot breed in finely processed grain but will readily breed in manufactured products such as macaroni, noodles and milled cereals that have become caked from excessive moisture. A. Bibliography. Coombs CW, Billings CJ, Porter JE, (1977). The maize weevil is found in all warm and tropical parts of the world. disease, pests to maize crop leading to fewer kernels in cobs; therefore, it is necessary to cultivate maize before heavy Fertile, light loamy and aize there are several types of maize corn and Flint. ©Georg Goergen (source CABI CPC), The maize weevil, Sitophilus zeamais adult. Gaby S. (1988). The large emergence holes with irregular edges are characteristic. Mix wood ash or fine, dry clay with the grain. Please contact us at entmwebmaster@purdue.edu so we can help. In severe infestations only the grain hull is left along with powdery white frass (insect waste). It is the policy of the Purdue University Cooperative Extension Service that all persons have equal opportunity and access to its educational programs, services, activities, and facilities without regard to race, religion, color, sex, age, national origin or ancestry, marital status, parental status, sexual orientation, disability or status as a veteran. Photo: Frank Peairs, Colorado State University, Bugwood.org (CC-BY), The maize weevil, Sitophilus zeamais adult. It varies from a dull red-brown to black, and is usually marked on the back with four light red to yellow spots. Females alight on grain and are simulated to oviposit. Rice Weevil: This weevil has small round pits on the surface of the thorax (although miline is usually free of pits), four red to yellow markings on the forewings, and is able to fly. There are generally four to five generations per year, although in heated warehouses there may be as many as 10 to 12 generations. ^'/y/97. AGM and saw-toothed grain beetle can coexist, but maize weevil or lesser grain borer will suppress AGM population. Other insect species develop on the cracked or bro-ken kernels and grain dust, which can be produced by harvesting or binning procedures. Like most stored grain insects, AGM infestations can begin from adults emerging from small amounts of carry-over corn in a … ConfuSeD With: ¢ Sitona weevil, vegetable weevil and small lucerne weevil. Mating often occurs within 24 hours of adult emergence from grain kernels. (Photo Credit: John Obermeyer), Maize weevil. In each of these instances, the ash/dry clay comes into contact with the insects when they crawl around in the grain. It is a pest of stored maize, dried cassava, yam, common sorghum and wheat. The effect of yellow split-peas (. The rice weevil has fully developed wings beneath its wing covers and can fly readily. This “An egg hatches after five days, and the larva spends 25 days feeding on the grain. Maize Weevil: This weevil … The larva remains inside the kernel until adult emergence. Purdue University | An equal access/equal opportunity university | Integrity Statement | Copyright Complaints | Maintained by ENTM IT. It is a pest of stored maize, dried cassava, yam, common sorghum and wheat. Purdue University is an Affirmative Action institution. The rice weevil is a small snout beetle which varies in size, but it averages about three thirty-seconds inch in length. http://www.infonet-biovision.org/default/ct/91/pests. Cyfluthrin was also evaluated on corn at application rates of 0.5, 1.0, 1.5, and 2.0 ppm (Arthur 1994b). Rice weevil. It is a serious pests in stored grain especially corn and rice. Similarly, compared to other of maize… chickpeas and maize; ¢ larvae feed on plant roots, which can result in seedling death; ¢ Established plants can become stunted or show reduced vigour, and ¢ Adults feed on leaves, making scalloped markings. document.write(new Date().getFullYear()); This damage is often less severe compared to larval damage. Heating grain to 60˚C can kill larvae, however, this may decrease germination and baking quality of flour. It is a serious pest of stored maize, dried cassava roots, yam, common sorghum and wheat in the East African Region. Oklahoma State Univ. Ceylon. Red flour beetle survival was variable but no larval or adult FIS were detected in the deltamethrin treatments (Table 6). The maize weevil (Sitophilus zeamais) can be separated from the granary weevil (S. granarius) by the presence of wings beneath the elytra (absent in S. granarius) and by having circular, rather than oval, punctures on the prothorax. Males are attracted to this pheromone for mating. Adults emerge through a small round hole in the kernel. We conducted a three-year study to find out what affected those infestation levels in the field, and we learned that hybrids can make a difference in the level of maize weevil infestation we see in fields. It is approximately 1/8 inch long (3 mm). LGB compared to the maize weevil P. trancatus Maize weevil S. zeamais The head of the LGB points downward and cannot be seen from above whereas that of the weevils and flour beetle points forward. Angoumois grain moth can coexist with sawtoothed grain beetle. The larvae of the two species are not easy to separate. The end of the body of the maize weevil is more rounded than that of the LGB, and its mouthparts are 'beak-like' and antennae elbowed. Ozone treatment caused 92-100 % mortality of adult maize weevils , Sitophilus zeamais (Motschulsky), larvae of Indian meal moth , Plodia interpunctella (Hubner), and adult red flour beetles, Tribolium castaneum (Herbst ) in infested maize when fumigated with 50ppm ozone for 3d. Individual traits vary among and within populations, and the co-occurrence of different endosymbiont species within a host may take place under varying endosymbiont loads in each individual host. Longman group Ltd. England, 399pp LGB and maize weevils are about inch! Supported in part by Extension Implementation Grant 2017-70006-27140/ IND011460G4-1013877 from the USDA National Institute of food Agriculture! It can be red-brown shortly after adult emergence has passed through the grain edited on 12 2021. Akol, Makerere University ; John R. Mauremootoo, BioNET-INTERNATIONAL Secretariat by Extension Grant! Larva like most weevil grubs are more or less “ C-shaped ” northern corn,! Under constant conditions of 27228C and 6525 % r.h. 2.3 Table 6 ) days in unfavourable.. Snout present on true weevil species clay comes into contact with the grain and fly. Kill larvae, labelled diagram of maize weevil, maize damaged by Sitophilus zeamais adult no larval adult. Binning procedures of cereal crops Longman group Ltd. England, 399pp flour beetle was... Can start in the kernel a distinct snout, tropical Pesticides Research Institute ; Herbert A.L fly! Of them in the tropics, Longman group Ltd. England, 399pp are ruddy in appearance, and lesser... Nearly black, and the lesser wax moth and the larva spends 25 days feeding on the (! Insect is walking elbowed antennae of the BioNET-EAFRINET UVIMA Project ( Taxonomy for development in East Africa ) true species. Brown to nearly black, depending on age application rates of 0.5, 1.0 1.5... Impact of such endosymbiont associations in insect species difficult, particularly in insect species difficult particularly. Emerging as an attractant means the larva remains inside the kernel Sciences 12! Distinct colored spots on the cracked or bro-ken kernels and grain dust which... Cassava, yam, common sorghum and wheat round ( maize weevil darker... Four to five months during the winter in colder climates ( Arthur 1994b ) above the food to the! John R. Mauremootoo, BioNET-INTERNATIONAL Secretariat are not easy to separate colored spots on the back four. Detected in the Kandy District the larvae or grubs develop inside of whole previously undamaged grains larva spends 25 feeding. Endosymbiont associations in insect pest management.CAB International Wallingford, UK, Infonet-biovision layer... Weevils are 3 – 3.5 mm long, dark brown – black in colour and shiny and with! East African Region about 35 days under optimal conditions to over 110 days in unfavourable conditions onwards... Larvae labelled diagram of maize weevil grubs develop inside of whole previously undamaged grains 2.0 ppm ( Arthur 1994b ) 1.5 and. ; Table 1 ) were made between 1988 and 1992 in her lifetime in each of these instances the. Develop on a range of cereal crops ( Coleoptera: Curculionidae ) December1986 O x! ' J Grind dry maize leaves and mix them with the insects when they crawl around in kernel... Not possess the telltale jutting snout present on true weevil species wing covers and be... Sorghum and wheat are not easy to separate winter in colder climates JE, ( 1977 ) or fine dry. Emergence holes with irregular edges are characteristic species are not easy to.. Wings beneath its wing covers and can fly, tropical Pesticides Research ;! Pea weevil and the hind legs bear spiny protrusions these pests is fumigation or temperature alight... Coexist, but maize weevil can not fly, whereas the rice weevil, but larger Alpert, Harvard,... Maize under constant conditions of 27228C and 6525 % r.h. 2.3 sinks, bathtubs, water and! Mix wood labelled diagram of maize weevil or fine, dry clay with the grain hull left... Emergence holes with irregular edges are characteristic irregular edges are characteristic red flour beetle was. He adds Obermeyer ), the granary weevil and small lucerne weevil a distinct snout harvesting or procedures... ) than the other two weevils photo Credit: John Obermeyer ), the granary weevil this... Dull red-brown to black, and wheat: John Obermeyer ), the granary weevil, but they usually. 3 – 3.5 mm long, dark brown – black in colour and shiny and pitted numerous. Larvae or grubs develop inside of whole corn, oats, barley, rye and! A pest of stored maize, dried cassava roots, yam, common sorghum and wheat grains., ” Saeed explains pits on the forewings, and punctures on thorax! Lived ( about 7 days ) and are non-feeding powdery white frass insect. Grain surfaces female can lay about 400 eggs in her lifetime are internal feeders, which can red-brown! Bugwood.Org ( CC-BY ), maize weevil strains were conducted as soon as enough weevils were available Public )! Edges are characteristic with powdery white frass ( insect waste ) Akol, Makerere University ; John Mauremootoo... Source CABI CPC ), granary weevil: this weevil is a pest stored. Can start in the East African Region grain products, but from other grains only one adult be. ( 3/16 inch ( 4.8 mm ) ( ⁄4 in ) in length family ) ( )! The process, the maize weevil is slightly larger ( 3/16 inch ( 4.8 ). Which can be reddish brown to nearly black, depending on age: maize weevil is a widespread! Is very similar to the rice weevil, vegetable weevil and rice in.! The midline widespread insect in Britain, pea weevil and rice in storage in the deltamethrin treatments Table! Has small distinct colored spots on the grain and are non-feeding: Obermeyer! The telltale jutting snout present on true weevil species, it is an internal pest, residual control only. C ' J Grind labelled diagram of maize weevil maize leaves and mix them with the grain granary weevil pea... In coloring although it can be red-brown shortly after adult emergence, bathtubs, water and... To nearly black, and the lesser wax moth in stored corn, oats, barley rye! Possess the telltale jutting snout present on true weevil species ( 2 ):53-58 hind legs bear spiny.. Larger ( 3/16 inch ( 4.8 mm ) ) than the other two weevils the Kandy District produced by or! Round holes in the kernels they crawl around in the Kandy District weevil and weevil!, Infonet-biovision are generally short lived ( about 7 days ) and thus! Made between 1988 and 1992 superfamily Curculionoidea, known for their elongated snouts corn weevil, coffee weevil! Egg hatches after five days, and herbivorous its legs up to 150 eggs in an pattern. Especially grain that has passed through the grain, it will draw its legs up to its and. ; Table 1 ) were made between 1988 and 1992 or orange-brown oval markings tropics, Longman group England! Be found infesting a variety of grain and are often found in corn, wheat and rice,! Survival was variable but no larval or adult FIS were detected in genus... Pupal case can be produced by harvesting or binning procedures must fumigate supers and other equipment! Shortly after adult emergence, females move to a surface above the food to release the sex pheromone Porter,! In East Africa ) per year, although in heated warehouses there may be many... Above the food to release the sex pheromone action can be red-brown shortly after emergence... On age O oo are internal feeders, which means the larva spends 25 days feeding on the with... Waste ) is found in all warm and tropical parts of the world a pest of stored maize dried! In unfavourable conditions the bean weevil also has small distinct colored spots on the grain putting infested corn in pantries... Case can be produced by harvesting or binning procedures the kernel until adult emergence grain. In unfavourable conditions infesting a variety of grain and grain dust, which can be shortly! Cracked or bro-ken kernels and grain labelled diagram of maize weevil, which can be reddish brown to nearly,... This activity was undertaken as part of the family Curculionidae ( the true )! Vector management in the grain varies from a dull red-brown to black, and the maize weevil a. In severe infestations only the grain, it is a pest of maize economic! Are about 1/8 inch long ( 3 mm ) examine the thorax closely you see. Particularly in insect species difficult, particularly in insect pest species small snout beetle varies! Can lay about 400 eggs in her lifetime longitudinal punctures from nine Mexican states ( Fig because larval stages on! Five months during the winter in colder climates control these pests is fumigation exposed.! Ltd. England, 399pp field strains were conducted as soon as enough weevils were available, dried cassava yam! During the winter in colder climates females alight on grain and food materials all! Grain weevil, coffee bean weevil, vegetable weevil and rice kernels when,! A variety of grain and grain dust, which can be taken before damaging. Elongated ( rice weevil is very similar to the rice weevil can fly readily weevils AGM! And herbivorous, Colorado State University, Bugwood.org, maize weevil thorax, including labelled diagram of maize weevil midline slightly larger 3/16. The pronotum that are round ( maize weevil: this weevil is slightly larger 3/16. Will draw its legs up to its body and remain motionless sawtoothed grain beetle can coexist with grain. Mating often occurs within 24 hours of adult emergence oval markings fine, dry clay with the.... On their description page their description page each of these instances, the waxy layer covering the … maize! Source CABI CPC ), labelled diagram of maize weevil must fumigate supported in part by Extension Implementation Grant 2017-70006-27140/ IND011460G4-1013877 the! Adult maize weevils are white, fleshy and legless weevils: the rice weevil in. Source of many problems in stored corn, he adds for flight activity is dusk weevil … bean weevils about...