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Datasheet

Sitophilus oryzae
(lesser grain weevil)

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Datasheet

Sitophilus oryzae (lesser grain weevil)

Summary

  • Last modified
  • 19 November 2018
  • Datasheet Type(s)
  • Invasive Species
  • Pest
  • Host Animal
  • Preferred Scientific Name
  • Sitophilus oryzae
  • Preferred Common Name
  • lesser grain weevil
  • Taxonomic Tree
  • Domain: Eukaryota
  •   Kingdom: Metazoa
  •     Phylum: Arthropoda
  •       Subphylum: Uniramia
  •         Class: Insecta

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Pictures

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PictureTitleCaptionCopyright
Sitophilus oryzae (lesser grain weevil or rice weevil); adult on rice grains. Colorado, USA.
TitleAdult
CaptionSitophilus oryzae (lesser grain weevil or rice weevil); adult on rice grains. Colorado, USA.
Copyright©Joseph Berger - CC BY 3.0 US
Sitophilus oryzae (lesser grain weevil or rice weevil); adult on rice grains. Colorado, USA.
AdultSitophilus oryzae (lesser grain weevil or rice weevil); adult on rice grains. Colorado, USA.©Joseph Berger - CC BY 3.0 US
Sitophilus oryzae (lesser grain weevil, rice weevil); close up of adult.
TitleAdult
CaptionSitophilus oryzae (lesser grain weevil, rice weevil); close up of adult.
Copyright©Olaf Leillinger - CC BY-SA 2.5
Sitophilus oryzae (lesser grain weevil, rice weevil); close up of adult.
AdultSitophilus oryzae (lesser grain weevil, rice weevil); close up of adult.©Olaf Leillinger - CC BY-SA 2.5
Sitophilus oryzae (lesser grain weevil or rice weevil); adults in rice grains.
TitleAdults
CaptionSitophilus oryzae (lesser grain weevil or rice weevil); adults in rice grains.
Copyright©James Litsinger
Sitophilus oryzae (lesser grain weevil or rice weevil); adults in rice grains.
AdultsSitophilus oryzae (lesser grain weevil or rice weevil); adults in rice grains. ©James Litsinger
Eggs, larvae and pupae are all found within tunnels and chambers bored in the grain and are thus not normally seen; larvae are apodous. Adults usually red-brown, dull with coarse microsculpture.
TitleLife history
CaptionEggs, larvae and pupae are all found within tunnels and chambers bored in the grain and are thus not normally seen; larvae are apodous. Adults usually red-brown, dull with coarse microsculpture.
CopyrightNRI/MAFF
Eggs, larvae and pupae are all found within tunnels and chambers bored in the grain and are thus not normally seen; larvae are apodous. Adults usually red-brown, dull with coarse microsculpture.
Life historyEggs, larvae and pupae are all found within tunnels and chambers bored in the grain and are thus not normally seen; larvae are apodous. Adults usually red-brown, dull with coarse microsculpture.NRI/MAFF

Identity

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Preferred Scientific Name

  • Sitophilus oryzae (Linnaeus)

Preferred Common Name

  • lesser grain weevil

Other Scientific Names

  • Calandra bituberculatus (F.)
  • Calandra frugilegus (De Geer)
  • Calandra funebris (Rey)
  • Calandra granarius (Stroem)
  • Calandra oryxae var. minor
  • Calandra oryzae Linnaeus
  • Calandra sasakii Tak.
  • Calendra oryzae Linnaeus
  • Curculio oryza Linnaeus
  • Curculio oryzae Linnaeus
  • Diocalandra oryzae Linnaeus
  • Sitophilus oryzae var. minor
  • Sitophilus sasakii (Takahashi)

International Common Names

  • English: rice weevil
  • Spanish: gorgojo común del arroz; gorgojo del arroz
  • French: charançon du riz
  • Portuguese: gorgulho do arroz; gorgulho do milho

Local Common Names

  • Denmark: risbille
  • Germany: Käfer, Reis-; Rüssler, Reis-
  • Iran: susske bereng
  • Israel: chidkonit haorez
  • Italy: calandra del riso
  • Japan: ko-kokuzo
  • Netherlands: rijstklander
  • Norway: rissnutebille
  • Turkey: pirinc biti

EPPO code

  • CALAOR (Sitophilus oryzae)

Taxonomic Tree

Top of page
  • Domain: Eukaryota
  •     Kingdom: Metazoa
  •         Phylum: Arthropoda
  •             Subphylum: Uniramia
  •                 Class: Insecta
  •                     Order: Coleoptera
  •                         Family: Dryophthoridae
  •                             Genus: Sitophilus
  •                                 Species: Sitophilus oryzae

Notes on Taxonomy and Nomenclature

Top of page The taxonomy of the Sitophilus group has been confused until recently, so that the value of much of the earlier literature on these insects has been reduced, because of the difficulty of knowing the species to which it refers.

First described by Linnaeus in 1798 as Curculio oryza, the first named species of the group was later revised by De Clairville and Scheltenburg in 1798 as Calandra oryzae, which uses the commonest generic synonym for Sitophilus. Many workers subsequently recognized that two distinct forms of the species existed, which were described as the 'large' and 'small' forms. In 1855, Motschulsky recognized the large form as a distinct species, which he named Sitophilus zeamais. Unfortunately, few workers recognized this revision and the name Calandra oryzae continued to be applied to all insects in this complex. Takahashi in 1928 and 1931 complicated matters by raising the small form to specific status as Calandra sasakii. This confused situation continued until 1959, when Floyd and Newsom (1959) revised the complex; this was followed by a further revision by Kuschel (1961). In these revisions it was shown that Linnaeus originally described the smaller species and that Motschulsky's description of the larger species was valid. Both species were therefore placed in the genus Sitophilus with the specific names proposed by Linnaeus and Motschulsky.

Unfortunately, the size difference between S. oryzae and S. zeamais is not consistent, so it is not possible to be sure that references to the large and small forms of Calandra oryzae refer to S. zeamais and S. oryzae, respectively. Therefore the only true and unconfused synonym of S. oryzae is Calandra sasakii; in pre-1960s literature, C. oryzae 'small' and 'large' forms could refer to either S. zeamais or S. oryzae, and it is also possible that some references to 'S. oryzae' in the 1960s and early 1970s literature actually relate to S. zeamais misidentified by use of old keys. The genus Sitophilus and its species may be identified using the keys of Gorham (1987) or Haines (1991).

Description

Top of page Eggs, Larvae and Pupae

These developmental stages are all found within tunnels and chambers bored in the grain and are thus not normally seen. The eggs are shiny, white, opaque and ovoid to pear-shaped. The larva is white, stout and legless. The pupa is also white but has legs, wings, and the snout of the fully-grown weevil.

Adults

Usually red-brown, dull with coarse microsculpture. Scutellum usually with lateral elevations closer together than their length and evidently more than half as long as scutellum.

Males with median lobe of aedeagus evenly convex dorsally in cross section.

Females with lateral lobes of internal, Y-shaped sclerite broader and rounded apically, more narrowly separated.

S. oryzae and S. zeamais are almost indistinguishable from each other externally; identification is by exmaination of the genitalia. Both have the characteristic rostrum and elbowed antennae of the family Curculionidae. The antennae have eight segments and are often carried in an extended position when the insect is walking. Both species usually have four pale reddish-brown or orange-brown oval markings on the elytra, but these are often indistinct. (See also S. zeamais.)

Both species can be separated from S. granarius by the presence of wings beneath the eltyra (absent in S. granarius) and by having circular, rather than oval, punctures on the prothorax.

Distribution

Top of page S. zeamais and S. oryzae are found in all warm and tropical parts of the world, but S. oryzae may also be found in temperate climates. The earlier confusion over the identity of S. zeamais and S. oryzae, and the fact that most of the major basic studies were made before the confusion was resolved, means we cannot be sure to which of the species many of the observations refer. For a distribution map, see S. zeamais data sheet.

The detailed map plotted on the basis of actual country records gives a falsely restricted distribution. These pests are carried all over the world in grain shipments and can establish themselves wherever there is food and where grain moisture and temperature are favourable. In various locations, one species may be more common than the other. A global survey of resistance to pesticides (Champ and Dyte, 1976) contains detailed location lists for both species.

Distribution Table

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The distribution in this summary table is based on all the information available. When several references are cited, they may give conflicting information on the status. Further details may be available for individual references in the Distribution Table Details section which can be selected by going to Generate Report.

Continent/Country/RegionDistributionLast ReportedOriginFirst ReportedInvasiveReferenceNotes

Asia

BangladeshPresentCAB ABSTRACTS Data Mining 2001
BhutanPresentCAB ABSTRACTS Data Mining 2001
ChinaPresentCAB ABSTRACTS Data Mining 2001
IndiaPresentCAB ABSTRACTS Data Mining 2001; Rajendran et al., 2001; Kumar et al., 2005; Kumawat, 2007
IndiaPresentCAB ABSTRACTS Data Mining 2001; Rajendran et al., 2001; Kumar et al., 2005; Kumawat, 2007
IndiaPresentCAB ABSTRACTS Data Mining 2001; Rajendran et al., 2001; Kumar et al., 2005; Kumawat, 2007
IndiaPresentCAB ABSTRACTS Data Mining 2001; Rajendran et al., 2001; Kumar et al., 2005; Kumawat, 2007
-Andhra PradeshPresentVisalakshi et al., 2005
-Arunachal PradeshPresentPathak and Jha, 2003
-AssamPresentPathak and Jha, 2003
-BiharPresentCAB ABSTRACTS Data Mining 2001
-DelhiPresentCAB ABSTRACTS Data Mining 2001; Saravanan and Gujar, 2006
-DelhiPresentCAB ABSTRACTS Data Mining 2001; Saravanan and Gujar, 2006
-Indian PunjabPresentCAB ABSTRACTS Data Mining 2001; Rajendran et al., 2001
-Indian PunjabPresentCAB ABSTRACTS Data Mining 2001; Rajendran et al., 2001
-KarnatakaPresentCAB ABSTRACTS Data Mining 2001
-ManipurPresentCAB ABSTRACTS Data Mining 2001
-MeghalayaPresentPathak and Jha, 2003
-MizoramPresentPathak and Jha, 2003
-NagalandPresentPathak and Jha, 2003
-OdishaPresentCAB ABSTRACTS Data Mining 2001
-RajasthanPresentKumawat, 2007
-SikkimPresentPathak and Jha, 2003
-Tamil NaduPresentKumar et al., 2005
-TripuraPresentPathak and Jha, 2003
-West BengalPresentCAB ABSTRACTS Data Mining 2001
IndonesiaPresentPresent based on regional distribution.
-JavaPresentCAB ABSTRACTS Data Mining 2001
IranPresentCAB ABSTRACTS Data Mining 2001; Forghani and Marouf, 2015
IraqPresentCAB ABSTRACTS Data Mining 2001
IsraelPresentCAB ABSTRACTS Data Mining 2001
JapanPresentCAB ABSTRACTS Data Mining 2001
Korea, Republic ofPresentCAB ABSTRACTS Data Mining 2001
MalaysiaPresentCAB ABSTRACTS Data Mining 2001
NepalPresentCAB ABSTRACTS Data Mining 2001
PakistanPresentCAB ABSTRACTS Data Mining 2001
South East AsiaPresentCAB ABSTRACTS Data Mining 2001
Sri LankaPresentCAB ABSTRACTS Data Mining 2001
TaiwanPresentCAB ABSTRACTS Data Mining 2001

Africa

CameroonPresentNgamo et al., 2007
Central African RepublicPresentCAB ABSTRACTS Data Mining 2001
ChadPresentTrematerra et al., 2003
CongoPresentMunyuli bin Mushambanyi T, 2003
Côte d'IvoirePresentCAB ABSTRACTS Data Mining 2001
EgyptPresentCAB ABSTRACTS Data Mining 2001
EthiopiaPresentCAB ABSTRACTS Data Mining 2001
GhanaPresentKestenholz, 2001
KenyaPresentLikhayo and Hodges, 2000
MaliPresentCAB ABSTRACTS Data Mining 2001
MoroccoPresentBenhalima et al., 2004
NigeriaPresentCAB ABSTRACTS Data Mining 2001
SenegalPresentCAB ABSTRACTS Data Mining 2001
SomaliaPresentCAB ABSTRACTS Data Mining 2001
South AfricaPresentCAB ABSTRACTS Data Mining 2001
SudanPresentCAB ABSTRACTS Data Mining 2001
TanzaniaPresentCAB ABSTRACTS Data Mining 2001

North America

CanadaPresentKarunakaran et al., 2003
USAPresentCAB ABSTRACTS Data Mining 2001
-CaliforniaPresentCAB ABSTRACTS Data Mining 2001
-FloridaPresentCAB ABSTRACTS Data Mining 2001
-GeorgiaPresentCAB ABSTRACTS Data Mining 2001
-HawaiiPresentCAB ABSTRACTS Data Mining 2001
-IndianaPresentCAB ABSTRACTS Data Mining 2001
-KansasPresentCAB ABSTRACTS Data Mining 2001
-MichiganPresentCAB ABSTRACTS Data Mining 2001
-MinnesotaPresentCAB ABSTRACTS Data Mining 2001
-OklahomaPresentCAB ABSTRACTS Data Mining 2001
-South CarolinaPresentCAB ABSTRACTS Data Mining 2001

Central America and Caribbean

CubaPresentCAB ABSTRACTS Data Mining 2001
DominicaPresentTilley et al., 2007

South America

ArgentinaPresentCAB ABSTRACTS Data Mining 2001
BoliviaPresentCAB ABSTRACTS Data Mining 2001
BrazilPresentCAB ABSTRACTS Data Mining 2001
PeruPresentCAB ABSTRACTS Data Mining 2001

Europe

AustriaPresentCAB ABSTRACTS Data Mining 2001
BelarusPresentOvcharenko et al., 2004
BelgiumPresentCAB ABSTRACTS Data Mining 2001
CroatiaPresentHamel, 2007
Czech RepublicPresentStejskal et al., 2004
GermanyPresentCAB ABSTRACTS Data Mining 2001
GreecePresentCAB ABSTRACTS Data Mining 2001
ItalyPresentCAB ABSTRACTS Data Mining 2001
PolandPresentCAB ABSTRACTS Data Mining 2001
Russian FederationPresentOvcharenko et al., 2004
SpainPresentRiudavets et al., 2002
SwitzerlandPresentCAB ABSTRACTS Data Mining 2001
UKPresentCAB ABSTRACTS Data Mining 2001
UkrainePresentMishchenko et al., 2000

Oceania

AustraliaPresentCAB ABSTRACTS Data Mining 2001
-New South WalesPresentCAB ABSTRACTS Data Mining 2001
-QueenslandPresentCAB ABSTRACTS Data Mining 2001
-VictoriaPresentCAB ABSTRACTS Data Mining 2001
New ZealandPresentCAB ABSTRACTS Data Mining 2001

Habitat List

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CategorySub-CategoryHabitatPresenceStatus
Terrestrial

Hosts/Species Affected

Top of page Both S. oryzae and S. zeamais are able to develop on a wide range of cereals and also on processed cereal products such as pasta. However, food preferences of the two species are variable; it is clear that S. zeamais is predominantly found associated with maize grain, whereas S. oryzae is associated with wheat.

In the case of rice, detailed surveys in Indonesia have shown that S. zeamais is dominant on milled rice, whereas S. oryzae is more common on paddy (rough rice). Laboratory studies have shown that this is a result of their different rates of increase on these two forms of rice (Hussain et al., 1985). It is not yet known whether these relationships with the form of rice hold true throughout the tropics, but imports of milled rice into the UK from many countries are much more frequently infested by S. zeamais than by S. oryzae.

Both species are able to breed on dried cassava and have been reported as frequent pests of this commodity. A few strains of S. oryzae have been found which can develop on grain legumes (Coombs et al., 1977): peas, lentils and green or black gram are the pulses most often attacked by these strains.

Although S. oryzae is primarily a pest of stored products, it can also attack cereal plants in the field.

Growth Stages

Top of page Post-harvest

Symptoms

Top of page The eggs, larvae and pupae are not normally seen because they develop inside intact grains. The larvae chew large, irregular holes in the germ and endosperm of the kernel. Adult emergence holes (about 1.5 mm diameter) with irregular edges are apparent some weeks after the initial attack. Two rice weevils may develop at the same time on two sides of a single kernel. Adults can be found wandering over the surface of grain. In a heavy infestation, the only part of a grain that remains is the shell of the kernel perforated by adult feeding and emergence holes.

List of Symptoms/Signs

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SignLife StagesType
Seeds / internal feeding

Biology and Ecology

Top of page The earlier confusion over the identity of S. zeamais and S. oryzae, and the fact that most of the major basic studies were made before the confusion was resolved, means we cannot be sure to which of the species many of the observations refer. The development of the two species is clearly very similar, but there are probably a number of differences in the effects of environmental factors. Thus, the information given below may be taken as generally applicable to both species, but it should be remembered that there may be specific differences in details.

The biology of S. zeamais and S. oryzae has been reviewed in detail by Longstaff (1981). The adults are long-lived (several months to one year). Eggs are laid throughout most of the adult life, although 50% may be laid in the first 4-5 weeks; each female may lay up to 150 eggs. The eggs are laid individually in small cavities chewed into cereal grains by the female; each cavity is sealed, thus protecting the egg, by a waxy secretion (usually referred to as an 'egg-plug') produced by the female. The incubation period of the egg is about 6 days at 25°C (Howe, 1952). Eggs are laid at temperatures between 15 and 35°C (with an optimum around 25°C) and at grain moisture contents over 10%; however, rates of oviposition are very low below 20°C or above 32°C, and below about 12% moisture content (Birch, 1944).

Upon hatching, the larva begins to feed inside the grain, excavating a tunnel as it develops. There are four larval instars: in English wheat at 25°C and 70% RH, pupation occurs after about 25 days, although development periods are extremely protracted at low temperatures (e.g. 98 days at 18°C and 70% RH). Pupation takes place within the grain; the newly developed adult chews its way out, leaving a large, characteristic emergence hole. Total development periods range from about 35 days under optimal conditions to over 110 days in unfavourable conditions (Birch, 1944; Howe, 1952). The actual length of the life cycle also depends upon the type and quality of grain being infested: for example, in different varieties of maize, mean development periods of S. zeamais at 27°C and 70% RH have been shown to vary from 31 to 37 days.

Bhuiyah et al. (1990) determined the egg, larval and pupal periods for S. oryzae on maize in the laboratory as 5-6 days, 16-20 days and 8-9 days, respectively, at 23-35°C and 79-87% RH. The longevity of adult males and females was 114-115 days and 119-120 days.

Trematerra et al. (1996) developed a method for analysis and comparison of the development rate of S. oryzae on different cereals (Triticum aestivum, T. dicoccum, T. durum, T. monococcum and T. spelta). Yoon et al. (1997) constructed a matrix model of S. oryzae populations based on degree-days. The behavioural activity of S. oryzae towards intact and damaged kernels of Triticum aestivum, T. durum, T. dicoccum, T. monococcum and T. spelta was investigated by Trematerra et al. (1999).

Although both species are capable of flight, S. zeamais has a greater ability and tendency to fly (Giles, 1969). Where grain is stored on small farms, S. zeamais is thus more likely than S. oryzae to fly to the ripening crop in the field and establish an infestation in the grain before harvest.

Natural enemies

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Natural enemyTypeLife stagesSpecificityReferencesBiological control inBiological control on
Acaropsellina docta Predator Larvae/Pupae
Anisopteromalus calandrae Parasite Larvae/Pupae
Bacillus thuringiensis thuringiensis Pathogen
Beauveria bassiana Pathogen
Carcinops troglodytes Predator
Cerocephala dinoderi Parasite Larvae
Cerocephala oryzae Parasite Larvae
Lariophagus distinguendus Parasite Larvae/Pupae
Microsporidium sitophili Pathogen
Pteromalus cerealellae Parasite
Tenebroides mauritanicus Predator
Theocolax elegans Parasite Larvae/Pupae

Notes on Natural Enemies

Top of page Both S. zeamais and S. oryzae are commonly parasitized by pteromalids (and occasionally other Hymenoptera). Common pteromalid parasites found in the Tropics include Anisopteromalus calandrae, Lariophagus distinguendus and Choetospila elegans [Theocolax elegans].

Impact

Top of page Introduction

S. oryzae is universally regarded as one of the most destructive primary pests of stored cereals such as barley, maize, rice and wheat. It does not often breed in noncereal foods, although it does attack split peas and pasta. It can attack cereal plants in the fields. Voracious feeding on whole grains by this insect results in weight loss, fungal growth, quality loss through an increase in free fatty acids and it can even completely destroy stored grain in all types of storage. Invasion by this primary pest may cause grain heating and may facilitate the establishment of fungal colonies, secondary insect pests, and mite pests.

S. oryzae and S. zeamais are very important pests of cereals. In maize or sorghum, attack may start in the mature crop when the moisture content of the grain has fallen to 18-20%. Subsequent infestations in storage result from the transfer of infested grain into stores or from the pest flying into storage facilities, probably attracted by the odour of the stored grain.

In stored maize, heavy infestations of these pests may cause weight losses of up to 30-40%, although losses are commonly 4-5%.

Generally, both adults and larvae feed on whole cereal grains, including wheat, rice, barley, maize, groundnuts, cassava, beans, millet, and sorghum; but the females can lay eggs and develop on solid products made of cereals, such as pasta. S. oryzae can infest maturing grain, especially maize in the field, in the southern USA and in other warm and tropical regions.

Barley

Boles and Pomeranz (1978) reported a wide variation in numbers of progeny observed among barley samples from different locations as well as among samples of individual varieties. Blue aleurone-layered barleys produced slightly fewer progeny of S. oryzae than the white aleurone-layered barleys. Singh et al. (1991) reported varietal susceptibility of barley grains to S. oryzae.

In Egypt, weight losses attributable to S. oryzae and S. granarius in grain stored, under natural conditions, at 25°C and 70% RH, were about 79-81% in barley (Koura and El-Halfawy, 1972).

Maize

According to Kamel and Zewar (1973), an increase of 1% in mean infestation resulted in a decrease of 0.35% in the weight of maize kernels and a 0.41% weight decrease in millet kernels. Losses in stored grains of five high-yielding hybrid varieties of maize were determined in Uttar Pradesh, India, by Karan Singh et al. (1974). Significant differences in weight loss were found between the varieties and varied from 1.3% to 4.5%. Rodriguez (1976) reported damage to stored maize in the Mexican state of Yucatan. Weight loss during storage (4-5 months) reached 30%, and most damage was caused by S. oryzae.

When 170 1-day-old adults of S. oryzae were released into 2 kg sacks of maize, 88.51% infestation and 38.12% weight loss of grains were recorded by Bhuiyah et al. (1990) after 6 months. Loss in weight and viability in five maize hybrids revealed a significant difference due to hybrids, pests and their interactions (Kurdikeri et al., 1993). Percentage seed damage and loss in weight increased with the increase in storage period in all the maize hybrids, while the viability of seeds decreased (Kurdikeri et al., 1994).

Khare et al. (1974) reported that over an 18 month period, the loss in protein content in damaged grain varied from 8.76 to 50.85 mg/g. Matioli (1981) reported that weight loss, frass volume and percentage of damaged grains varied according to the variety of maize. Pericarp hardness was associated with resistance at low rates of infestation, but at higher infestation rates, carbohydrate content seemed to be more important. According to the variety concerned, the endosperm, pericarp and embryo were the preferred food (De and Prakash, 1989).

Rice

According to Rubbi and Begum (1986), in Bangladesh the population of Sitotroga cerealella was highest, followed by S. oryzae and then Rhyzopertha dominica, and the percentage loss in weight of the rice followed the same order.

Sittisuang and Imura (1987) reported that brown rice lost 19% of initial kernel weight over 14 weeks of infestation with S. oryzae. In India, stored rice (unhusked) samples, drawn from six districts of Himachal Pradesh, were infested with S. oryzae (69%); the average weight loss in storage was 2.11%, and ranged from 1.09% to 3.10% (Thakur and Sharma, 1996). The effect of feeding by larvae and adults of S. oryzae on the weight of rice and wheat grain was determined in laboratory tests. The maximum weight loss caused to single kernels by individual larvae was 57% for rice and 19% for wheat (Banerjee and Nazimuddin, 1985).

In Egypt, weight losses attributable to S. oryzae and S. granarius in grain stored, under natural conditions, at 25°C and 70% RH, ranged from 56-74% in rice (Koura and El-Halfawy, 1972).

Sorghum

In Maharashtra, India, some hybrids and varieties of sorghum were less susceptible to attack by S. oryzae than local varieties (Borikar and Tayde, 1979). Torres et al. (1996) conducted laboratory observations with 29 sorghum varieties to study resistance to S. oryzae. The relative resistance of 36 improved and local sorghum varieties were also assessed in Nigeria (at Samaru) (Bamaiyi et al., 1998).

In Georgia, USA, 21 varieties of sorghum were assessed for losses during storage for up to 9 weeks at 30°C and 72% RH. The loss in grain sample weight from damage by S. oryzae varied from 4 to 52% (McMillian et al., 1981).

Weight loss in sorghum grains in large and small grains was 0.32 and 0.41%, respectively (Shazali, 1987). Threshed grain was more susceptible than unthreshed grain; more progeny were produced on threshed than on unthreshed sorghum (Wongo and Pedersen, 1990).

Wheat

On wheat after 65 days, the average proportion of damaged grains ranged from 0.05% to 42%; the loss in weight ranged from 0.43% to 21.02% (Singh and Mathew, 1973).

A survey in Uttar Pradesh, India, showed that the weight loss after storage for 6 months varied from 0.06 to 9.7%, and the loss in viability from 7.0% to 22.0%. In 12 districts of the Indian Punjab, after about 8-10 months storage on the farm, the weight loss was about 2.5% (Bhardwaj et al., 1977).

In the UK, wheat grain infested with S. oryzae and stored at 27°C and 70% RH for 14 weeks revealed losses of up to 38%, and a loss of 18% of the original protein fraction (Francis and Adams, 1980).
Levchenko and Imshenetskii (1984) reported that of 10 wheat varieties studied, there were significant differences in the damage done by S. oryzae and S. granarius.

In the tropics, cereal grain insects including S. oryzae cause an estimated overall yield loss of up to 30%, especially under inadequate storage methods (Singh and Benazet, 1974). In Ethiopia, the major species of stored product pests include S. oryzae, S. granarius and S. zeamais on whole grains. A weight loss of 4.2% of wheat stored in traditional stores was attributed to Sitophilus spp. (Hulluka, 1991).

In Egypt, weight losses attributable to S. oryzae and S. granarius in grain stored under natural conditions, at 25°C and 70% RH, ranged from 36-40% in wheat (Koura and El-Halfawy, 1972).

Other Crop Losses

Bandyopadhyay and Ghosh (1999) investigated the loss of stored rice and wheat under different climatic conditions in West Bengal, India. Grain damage was found throughout the year in all the localities, and ranged from 3 to 15.5% at Purulia, 4.7 to 23.4% at Kalyani and 4.4 to 20.4% at Cooch Behar on rice, and 4.3 to 21.8%, 6.4 to 25.5% and 4.5 to 22.2% on wheat, respectively.

In Egypt, on local maize, millet and wheat varieties in storage, the relationship between total infestation and external infestation, weight loss, the number of insect fragments in milled grain and the moisture content of the kernels were investigated by Omar and Kamel (1980-1981). Weight loss was negligible unless infestation exceeded 5%, but otherwise the correlation between weight loss and total infestation was linear, with variations for different grain types and insect species. The correlation between insect fragments and total infestation was positive up to a certain infestation level (varying with grain type and insect species) but became negative when infestation exceeded that level. The moisture content of infested grains was positively correlated with the level of infestation in all cases.

Detection and Inspection

Top of page Flight traps will collect S. zeamais, but seldom S. oryzae (which rarely flies). In milled rice stores, bag traps baited with brown rice have captured both species (Hodges et al., 1986). Disturbance of the grain causes adult Sitophilus spp. to migrate upwards and become visible on the surface.

A male aggregation pheromone attracts both sexes in S. oryzae (Phillips and Burkholder, 1981). Trematerra and Girgenti (1989) investigated the influence of pheromone and food attractants on trapping S. oryzae. Levinson et al. (1990) confirmed the activity of 4S,5R sitophinone and 2S,3R-sitophilate for S. oryzae, S. zeamais and S. granarius using electro-antennogram-recordings. The effect of insect age on the response of Sitophilus species to 4S,5R-sitophilure and food volatiles was reported by Wakefield (1998). For further information, see Plarre (1998).

A WB Probe II Trap was used to monitor insect activity in grains in the laboratory at 24±1°C and 70±5% RH (Trematerra, 1998). In all cereals examined, the traps trapped more S. oryzae than Tribolium castaneum and Oryzaephilus surinamensis. The effectiveness of a 'stored grain insect trap' was tested on heavily infested paddy and wheat grains in India (Rajkumar and Anitha, 1998). The results showed that all larvae and adults of S. oryzae were collected. The collection of larval forms with this trap is reported for the first time.

Similarities to Other Species/Conditions

Top of page S. oryzae and S. zeamais can be separated from 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.

Some molecular and morphological markers for the diagnosis of S. oryzae and S. zeamais are reported in Hidayat et al. (1994).

Prevention and Control

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Cultural Control and Sanitary Methods

Good store hygiene plays an important role in limiting infestation by S. oryzae and S. zeamais. The removal of infested residues from last season's harvest is essential.

Chemical Control

Grain may be protected by the admixture of insecticide. Sitophilus spp. have a low susceptibility to synthetic pyrethroids but are readily killed by organophosphorous compounds such as fenitrothion and pirimiphos-methyl. Grain stocks may be fumigated with phosphine to eliminate existing infestation, but these treatments provide no protection against re-infestation. Sitophilus spp., particularly in the pupal stage, have a lower natural susceptibility to the fumigant phosphine and to carbon dioxide used in controlled atmosphere storage than do other species tested and thus inadequate treatments are particularly likely to result in some survival.

In laboratory tests to determine the toxicity of deltamethrin, fluvalinate, chlorpyrifos-methyl, etrimfos and malathion against Sitophilus zeamais and S. oryzae, etrimfos was found to be the most toxic insecticide to S. oryzae (Srinivasacharayulu and Yadav, 1997).

A mixture of fenitrothion, esfenvalerate and piperonyl butoxide was found to be effective against S. oryzae in stored rice until 180 days after treatment (Pinto et al., 1997).

The effects of phosphine on the pupae of S. oryzae, S. zeamais and S. granarius were studied at 15°C. No significant differences were found in pupal mortality between phosphine and the mixture with carbon dioxide (Goto et al., 1996). Mixtures of phosphine plus carbon dioxide reduced levels of resistance to phosphine in populations of S. oryzae and Rhyzopertha dominica (Athie et al., 1998).

Carbonyl sulfide (as gas), carbon disulfide (as liquid) and ethyl formate (aqueous solution) were tested as fumigants in silos of wheat in Australia. Control of S. oryzae, Tribolium castaneum and Rhyzopertha dominica was 99-100% (Desmarchelier et al., 1998).

Modified Atmospheres

Raised levels of carbon dioxide are known to be toxic to many insect species, but S. oryzae has previously been shown to be one of the more tolerant species to this treatment. Annis and Morton (1997) reported acute mortality for all life stages of S. oryzae exposed to 15-100% carbon dioxide at 25°C and 60% RH.

The rates of carbon dioxide production and oxygen consumption by adult S.oryzae on wheat indicated that caution was needed when interpreting fumigant dosage/response data obtained in sealed systems where carbon dioxide concentrations exceed about 1% and changes in respiratory physiology start to occur (Damcevski et al., 1998).

The effectiveness of controlled atmosphere was verified using generators of inert gases, such as carbonic anhydride and nitrogen, for the disinfestation of wheat stored in vertical silos and horizontal stores (Contessi, 1999). No pest survived at environmental temperature 27°C and temperature of the cereal mass approx. 24°C, but Sitophilus survived when the treatment was less than 12 days. It is suggested that this technique could be used as an alternative to fumigation with toxic gases.

Diatomaceous Earth

Experiments were conducted using 36 different diatomaceous earths or formulations collected from the USA, Mexico, Canada, Australia, Japan, China and Macedonia. The results indicated that the efficacy of diatomaceous earth against insects depended on different properties of the diatom particles (Korunic, 1997). The source of diatomaceous earth, insect species, grain moisture content, temperature, method of application and duration of exposure all factors influenced the mortality of stored-product insects. For S. oryzae some diatomaceous earths had increased efficacy at lower temperatures and others had decreased efficacy at lower temperatures (Fields and Korunic, 2000).

Temperature

The effect of low temperatures on S. oryzae and S. zeamais was investigated by Nakakita et al. (1997). Both hatching and metamorphosis of each species were inhibited at 10°C. Population increase of S. oryzae was completely suppressed at 15°C, while a small number of F1 beetles of S. zeamais emerged.

When the pupae of S. oryzae, Corcyra cephalonica and Sitotroga cerealella were exposed to temperatures of 35-45°C for 24-72 h, S. oryzae was the most vulnerable species. A very high incidence of sterility was induced in the adults emerged from pupal exposures at 40°C (Sharma et al., 1997).

Beckett et al. (1998) used conductive heating to quickly obtain and maintain moderate temperatures in grain while minimising grain moisture loss (Beckett et al., 1998).

Radiation

S. oryzae was more susceptible to gamma radiation than S. granarius. Doses of Ú1.0 kGy resulted in 100% mortality within 3-6 days for S. granarius, and within 4 days for S. oryzae (Ignatowicz, 1997). A sterilizing dose of gamma radiation from Cobalt-60 was determined for adults of S. oryzae, S. zeamais, S. granarius on rice, maize and wheat grains as 70, 60 and 80 Gy, respectively (Franco et al., 1997).

Radio frequency and microwave dielectric properties of stored-grain insects were investigated and their implications for potential insect control are reported by Nelson et al. (1997, 1998).

Host-Plant Resistence

Laboratory studies were conducted on different sorghum varieties (Leuschner and Manthe, 1996) to study the relationship between resistance to S. oryzae and grain nutrient content (Torres et al., 1996). The relative resistances of 36 improved and local sorghum varieties were assessed in Nigeria (Bamaiyi et al., 1998). Eight land races of sorghum collected in Ethiopia showed significant variation by genotype in soluble phenolic content suggesting that the soluble phenolic content could be used as an indicator of resistance (Ramputh et al., 1999).

Chunni and Singh (1996) evaluated 64 wheat varieties for resistance to S. oryzae. Singh et al. (1998) screened 15 varieties of maize and Thakur (1999) and Thakur and Sharma (1996) screened 20 rice varieties.

Biological Control

Biological control has not been practised against these species. There may be some potential for the development of pest management strategies that favour the action of natural parasites.

Botanical extracts

A number of plant extracts have been tested for activity against S. oryzae including Ocimum basilicum, Capsicum frutescens, Piper guineense, Tetrapleura tetraptera and Eichhornia crassipes (Gakuru and Foua-Bi, 1996); Dicoma sessiliflora and Neorautanenia mitis (Chimbe and Galley, 1996); Ricinus communis (Mahgoub and Ahmed, 1996); Labrador tea (Ignatowicz and Wesolowska, 1996); Melilotus officinalis and M.albus (Ignatowicz, 1997); Withania somnifera (El-Lakwah et al., 1997) ; Gardenia fosbergii (Kestenholz and Stevenson, 1998); many Asteraceae (Ignatowicz, 1998); Thujopsis dolabrata var. hondai (Ahn et al., 1998); Eucalyptus tereticornis (Khan and Shahjahan, 1998); Allium sp. (Trematerra and Lanzotti, 1999); Decalepis hamiltonii (George et al., 1999); Chenop;odium multifidum, Flaveria bidentis, Aristolochia argentina and Tagetes erecta (Broussalis et al., 1999).

Neem

Mohapatra et al. (1996) reported that alcohol extracts of Azadirachta indica were superior to aqueous extracts providing 100% protection to rice grains for 6 weeks at a concentration of 1%. The repellent effect of a neem formulation extracted from seeds was evaluated by Suss et al. (1997). Imti and Zudir (1997) reported the efficacy of neem leaf and kernel powders. Sharma (1999) suggested that neem products can be mixed with stored maize to protect the grains up to 9 months from the attack of the major pests. The average mortality of S. oryzae adults treated with Neemazal-W was high and reached 100% at all tested concentrations 14 days post-treatment (El-Lakwah and El-Kashlan, 1999).

References

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Abdulahi A, Haile A, 1991. Research on the control of insect and rodent pests of wheat in Ethiopia. Wheat research in Ethiopia: a historical perspective [edited by Gebre-Mariam, H.; Tanner, D. G.; Hullluka, M.] Addis Ababa, Ethiopia; Institute of Agricultural Research, 219-233

Ahn YoungJoon, Lee SeongBaek, Lee HoiSeon, Kim GilHa, 1998. Insecticidal and acaricidal activity of carvacrol and -thujaplicine derived from Thujopsis dolabrata var. hondai sawdust. Journal of Chemical Ecology, 24(1):81-90; 32 ref

Annis PC, Morton R, 1997. The acute mortality effects of carbon dioxide on various life stages of Sitophilus oryzae. Journal of Stored Products Research, 33(2):115-124; 20 ref

Asanov K, 1970. The lesser grain borer. Zashchita Rastenii, 15(10):47

AthiT I, Gomes RAR, Bolonhezi S, Valentini SRT, Castro MFPPMde, 1998. Effects of carbon dioxide and phosphine mixtures on resistant populations of stored-grain insects. Journal of Stored Products Research, 34(1):27-32; 27 ref

Aviles R, Guibert G, 1986. Crop residues as a reservoir of pests of stored rice. Ciencias de la Agricultura, No. 28:13-18

Ayuk-Takem JA, Chheda HR, Eckebil JP, 1982. Problems and potentials of maize research and production in Cameroon (Zea mays L.). Revue Science et Technique, 2(4):5-16

Bahr I, Prinz W, 1977. Insects in stored grain in the German Democratic Republic and the prevention of damage. Nachrichtenblatt fur den Pflanzenschutz in der DDR, 31(10):200-204

Bamaiyi LJ, Uvah II, Dike MC, Onu I, 1998. Relative resistance of some sorghum varieties to the rice weevil, Sitophilus oryzae (Linnaeus) (Coleoptera: Curculionidae). Journal of Sustainable Agriculture, 13(2):5-11; 13 ref

Bandyopadhyay B, Ghosh MR, 1999. Loss of food grains by insect pests during storage in three agroclimatic zones of West Bengal. Environment and Ecology, 17(3):701-705; 5 ref

Banerjee TC, Nazimuddin S, 1985. Weight loss of wheat and rice caused by feeding of the larvae and adults of Sitophilus oryzae Linn. and Rhizopertha dominica Fabr. Indian Journal of Agricultural Sciences, 55(11):703-706

Beckett SJ, Morton R, Darby JA, 1998. The mortality of Rhyzopertha dominica (F.) (Coleoptera: Bostrychidae) and Sitophilus oryzae (L.) (Coleoptera: Curculionidae) at moderate temperatures. Journal of Stored Products Research, 34(4):363-376; 25 ref

Benhalima H, Chaudhry MQ, Mills KA, Price NR, 2004. Phosphine resistance in stored-product insects collected from various grain storage facilities in Morocco. Journal of Stored Products Research, 40(3):241-249. http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6T8Y-48DXN7D-1&_user=3796239&_handle=V-WA-A-W-AU-MsSAYWW-UUW-U-AAWBZZDAYW-AAWAWVDEYW-WAEUWEUYE-AU-U&_fmt=summary&_coverDate=12%2F31%2F2004&_rdoc=1&_orig=browse&_srch=%23toc%235099%232004%23999599996%23470841!&_cdi=5099&view=c&_acct=C000000593&_version=1&_urlVersion=0&_userid=3796239&md5=35299199745821420ef2bee0db5a3c0c

Berger HK, Hetfleis M, 1985. Stored-product protection - pests and their control. Pflanzenschutz, 2:9-10

Bhardwaj AK, Srivastava PK, Girish GK, 1977. Assessment of storage losses in wheat due to insect damage in Punjab. Bulletin of Grain Technology, 15(2):126-129

Bhuiyah MIM, Islam N, Begum A, Karim MA, 1990. Biology of the rice weevil, Sitophilus oryzae (Linnpus). Bangladesh Journal of Zoology, 18(1):67-73

Birch LC, 1944. Two strains of Calandra oryzae L. (Coleoptera). Australian Journal of Experimental Biology and Medical Science, 22:271-275

Boles HP, Pomeranz Y, 1978. Comparative resistance of barleys as influenced by location source, aleurone layer, and protein levels. Proceedings of the North Central Branch of the Entomological Society of America, 33:29

Borikar PS, Tayde DS, 1979. Resistance in sorghum to Sitophilus oryzae Linn. Proceedings of the Indian Academy of Sciences, B, 88(1):273-276

Broussalis AM, Ferraro GE, Martino VS, Pinz=n R, Coussio JD, Calle Alvarez J, 1999. Argentine plants as potential source of insecticidal compounds. Journal of Ethnopharmacology, 67(2):219-223; 9 ref

Buchi R, 1993. Inquiry on the incidence of pests and the use of insecticides in granaries, feed stocks and mills. Landwirtschaft Schweiz, 6(1):10-12

Champ BR, Dyte CE, 1976. Report of the FAO global survey of pesticide susceptibility of stored grain pests. FAO Plant Production and Protection Series No. 5. Rome, Italy: Food and Agriculture Organisation of the United Nations

Chimbe CM, Galley DJ, 1996. Evaluation of material from plants of medicinal importance in Malawi as protectants of stored grain against insects. Crop Protection, 15(3):289-294; 36 ref

Chunni Ram, Singh VS, 1996. Resistance to Sitophilus oryzae in wheat and associated grain characteristics. Indian Journal of Entomology, 58(1):79-90; 12 ref

Clement G, Dallard J, Poisson C, Sauphanor B, 1988. The factors of paddy rice resistance to stored product insect pests. I. Influence of open lemma. Agronomie Tropicale, 43(1):47-58

Contessi A, 1999. Conservazione dei cereali mediante l'impiego di atmosfere modificate prodotte in loco. Tecnica Molitoria, 50(9):990-999

Coombs CW, Billings CJ, Porter JE, 1977. The effect of yellow split-peas (Pisum sativum L.) and other pulses on the productivity of certain strains of Sitophilus oryzae (L.) (Col. Curculionidae) and the ability of other strains to breed thereon. Journal of Stored Products Research, 13(2):53-58

Damcevski KA, Annis PC, Waterford CJ, 1998. Effect of grain on apparent respiration of adult stored-product Coleoptera in an air-tight system: implications for fumigant testing. Journal of Stored Products Research, 34(4):331-339; 21 ref

De D, Prakash S, 1989. Quantitative losses in the various kernel fractions of some maize varieties in storage due to Sitophilus oryzae Linn. Journal of Entomological Research, 13(1-2):57-59

Delobel A, 1992. Dried cassava chips, an important reservoir for stored-product insects in Central Africa. Journal of African Zoology, 106(1):17-25

Desmarchelier JM, Allen SE, Yonglin R, Moss R, Le Trang Vu, 1998. Commercial-scale trials on the application of ethyl formate, carbonyl sulphide and carbon disulphide to wheat. Technical Report - CSIRO Division of Entomology, No. 75:iii + 63 pp.; 20 ref

Deuse JPL, Pointel JG, 1975. Assessment of research at farm level storage in francophone Africa. Brady, E. U.; Brower, J. H.; Hunter, P. E.; Jay, E. G.; Lum, P. T. M.; Lund, H. O.; Mullen, M. A.; Davis, R. (Organisers): Proceedings of the First International Working Conference on Stored-Product Entomology, Savannah, Georgia, USA, October 7-11, 1974. Stored-Product Insects Research and Development Laboratory, ARS, USDA & Department of Entomology, Georgia University. Savannah & Athens, Georgia USA, 85-91

Elek JA, 1998. Treatment of adult Coleoptera with a chitin synthesis inhibitor affects mortality and development time of their progeny. Entomologia Experimentalis et Applicata, 88(1):31-39; 25 ref

El-Lakwah FA, El-Kashlan IH, 1999. Efficiency of Neemazal (powder 10%) against some stored product insects. Alexandria Journal of Agricultural Research, 44(2):271-283; 26 ref

El-Lakwah FA, Khaled OM, Khattab MM, Abdel-Rahman TA, 1997. Toxic effects of extracts and powders of certain plants against the rice weevil (Sitophilus oryzae (L.)). Annals of Agricultural Science, Moshtohor, 35(1):553-566; 20 ref

Evans NJ, 1985. The effectiveness of various insecticides on some resistant beetle pests of stored products from Uganda. Journal of Stored Products Research, 21(2):105-109

Fields P, Korunic Z, 2000. The effects of grain moisture content and temperature on the efficacy of diatomaceous earths from different geographical locations against stored-product beetles. Journal of Stored Products Research, 36(1):1-13

Floyd EH, Newsom LD, 1959. Biological study of the rice weevil complex. Annals of the Entomological Society of America, 52:687-695

Forghani SH, Marouf A, 2015. An introductory study of storage insect pests in Iran. Biharean Biologist, 9(1):59-62. http://biozoojournals.ro/bihbiol/index.html

Fortier G, Arnason JT, Lambert JDH, McNeill J, Nozzolillo C, Philogene BJR, 1982. Local and improved corns (Zea mays) in small farm agriculture in Belize, C.A.; their taxonomy, productivity, and resistance to Sitophilus zeamais. Phytoprotection, 63(2):68-78

Francis BJ, Adams JM, 1980. Loss of dry matter and nutritive value in experimentally-infested wheat. Tropical Science, 22(1):55-68

Franco SSH, Franco JG, Arthur V, 1997. Determinacao da dose esterilizante de radiacao gama do Cobalto-60 para Sitophilus oryzae, S. zeamais, S. granarius, em arroz, milho e trigo. Ecossistema, 22:120-121

Furiatti RS, Pereira PRVS, Pinto ARJr, Lazzari FA, 1999. Efficacy of insecticides to control Sitophilus oryzae (Linnaeus) (Coleoptera, Curculionidae) and Rhyzopertha dominica (Fabricius) (Coleoptera, Bostrichidae) in stored wheat. Revista Brasileira de Zoologia, 16(1):221-226; 14 ref

Gakuru S, Foua-Bi K, 1996. Effet d'extraits de plantes sur la bruche du niebe (Callosobruchus maculatus Fab.) et le charancon du riz (Sitophilus oryzae L.). Cahiers Agricultures, 5(1):39-42

Ganesalingam VK, 1977. Insects in paddy and rice in storage in the Kandy District. Ceylon Journal of Science, Biological Sciences, 12(2):169-176

Gelosi A, Arcozzi L, 1983. Maize weevil (Sitophilus zea-mays Motschulsky). Informatore Fitopatologico, 33(12):27-30

George J, Ravishankar GA, Pereira J, Divakar S, 1999. Bioinsecticide from swallowroot (Decalepis hamiltonii) Wight & Arn protects food grains against insect infestation. Current Science, 77(4):501-502; 17 ref

Giles PH, 1969. Observations in Kenya on the flight activity of stored products insects, particularly Sitophilus zeamais Motsch. Journal of Stored Products Research, 4:317-329

Girish GK, Tripathi BP, Tomer RPS, Krishnamurthy K, 1974. Studies on the assessment of losses. IV. Conventional grain storage practices and losses in rural areas in Uttar Pradesh. Bulletin of Grain Technology, 12(3):199-210

Gorham JR, 1987. Insect and mite pests in food: An Illustrated Key, Vols I and II. US Department of Agriculture, Agriculture Handbook Number 655

Goto M, Kishino H, Imamura M, Hirose Y, Soma Y, 1996. Responses of the pupae of Sitophilus granarius L., Sitophilus zeamais Motschulsky and Sitophilus oryzae L. to phosphine and mixtures of phosphine and carbon dioxide. Research Bulletin of the Plant Protection Service, Japan, No. 32:63-67; 10 ref

Haines CP, 1991. Insects and Arachnids of Tropical Stored Products: Their Biology and Identification (A Training Manual), 2nd edition. Chatham, UK: Natural Resources Institute

Hamel D, 2007. Storing maize in stores and protection from pests. (Cuvanje kukuruza u skladi?tu i za?tita od ?tetnika.) Glasilo Biljne Za?tite, 7(5):344-349

Hidayat P, Ffrench-Constant RH, Philipps TW, 1994. Molecular and morphological markers for diagnosis of Sitophilus oryzae and S. zeamais (Coleoptera: Curculionidae). Proceedings of the Seventh International Working Conference on Stored-product Protection, 2:1205-1226

Hodges RJ, Halid H, Rees DP, Meik J, Sarjono J, 1985. Insect traps tested as an aid to pest management in milled rice stores. Journal of Stored Products Research, 21(4):215-229

Hoppe T, 1986. Storage insects of basic food grains in Honduras. Tropical Science, 26(1):25-38

Howe RW, 1952. The biology of the rice weevil, Calandra oryzae (L.). Annals of Applied Biology, 39(1):68-180

Hussain I, Bin, Haines CP, Pranata RI, 1985. Susceptibility of paddy and milled rice to attack by Sitophilus oryzae (Linnaeus) and Sitophilus zeamais Motschulsky. In: Proceedings of the 6th Annual Workshop on Grain Post-Harvest Technology (Maintaining Good Grain Quality), Puncak Pass, Bogor, Indonesia, 3-6 May 1983, 147-156

Ignatowicz S, 1997. Post radiation mortality of adults of the grain weevil, Sitophilus granarius (L.), and the rice weevil, Sitophilus oryzae (L.). Annals of Warsaw Agricultural University, Agriculture, No. 31, 39-46

Ignatowicz S, 1997. Powdered herbs of the mint family (Lamiaceae) as insect repellents for protection of stored wheat grain. Polskie Pismo Entomologiczne, 66(1/2):135-149; 36 ref

Ignatowicz S, 1998. Powdered herbs of the daisy family (Compositae) as repellents or attractants for the grain weevil, Sitophilus granarius (L.), and the rice weevil, S. oryzae (L.). Annals of Warsaw Agricultural University SGGW, Horticulture (Landscape Architecture), No. 19:15-28; 24 ref

Ignatowicz S, Wesolowska B, 1996. Repellency of powdered plant material of the Indian neem tree, the Labrador tea, and the sweet-flag, to some stored product pests. Polskie Pismo Entomologiczne, 65(1/2):61-67; 16 ref

Imti B, Zudir T, 1997. Effect of neem; Melia azedarch (Linn) and Azadirachta indica (A. Juss) on the incidence of Sitophilus oryzae (Linn) (Coleoptera; Curculionidae) on stored paddy. Plant Protection Bulletin (Faridabad), 49(1/4):44-47; 7 ref

Kamel AH, Zewar MM, 1973. Loss in weight in stored corn and millet due to Sitophilus oryzae and Rhizopertha dominica infestations. Agricultural Research Review, 51(1):29-31

Karan Singh, Agrawal NS, Girish GK, 1974. Studies on the quantitative loss in various high yielding varieties of maize, due to Sitophilus oryzae (L.) Col., Curculionidae). Labdev Journal of Science and Technology, B, 12(1):3-4

Karunakaran C, Jayas DS, White NDG, 2003. Soft X-ray inspection of wheat kernels infested by Sitophilus oryzae. Transactions of the ASAE, 46(3):739-745

Kestenholz C, 2001. Repellent properties of Cassia sophera L. (Cesalpiniaceae) against the rice weevil Sitophilus oryzae L. (Coleoptera; Curculionidae) and the bruchid beetle Callosobruchus maculatus F. (Coleoptera; Bruchidae). Antenna (London), 25(1):53-56

Kestenholz C, Stevenson PC, 1998. Gardenia spp. as a source of botanical pesticide against the rice weevil, Sitophilus oryzae L. (Coleoptera, Curculionidae), in Sri Lanka. Brighton Crop Protection Conference: Pests & Diseases - 1998: Volume 2: Proceedings of an International Conference, Brighton, UK, 16-19 November 1998., 543-548; 6 ref

Khan M, Shahjahan RM, 1998. Evaluation of eucalyptus leaf extracts as repellent for adult Sitophilus oryzae (L.) (Col.: Curculionidae) and attractant for Callosobruchus chinensis (L.) (Col.: Bruchidae). Bangladesh Journal of Entomology, 8(1/2):81-88; 15 ref

Khare BP, Chaudhary RN, Singh KN, Sengar CS, 1974. Loss of protein due to insect feeding in maize (Zea mays L.). Indian Journal of Entomology, 36(4):312-315

Korunic Z, 1997. Rapid assessment of the insecticidal value of diatomaceous earths without conducting bioassays. Journal of Stored Products Research, 33(3):219-229; 18 ref

Koura A, El-Halfawy MA, 1972. Weight loss in stored grains caused by insect infestation in Egypt. Bulletin de la Societe Entomologique d'Egypte, 56:413-417

Kumar PP, Suganthy M, Nagapasupathi N, 2005. Integration of a mechanical device and a pea protein-rich fraction in removal of stored product insects from food grains. Journal of Ecotoxicology & Environmental Monitoring, 15(2):157-161

Kumawat KC, 2007. Assessment of losses due to insect pests under wheat storage practices in semi arid region. Annals of Plant Protection Sciences, 15(1):97-100. http://www.indianjournals.com/ijor.aspx?target=ijor:apps&type=home

Kurdikeri MB, Aswathaiah B, Katagall RD, Vasudevan S, Deshpande VK, 1994. Extent of seed damage, loss in weight and loss of viability due to infestation of the rice weevil Sitophilus oryzae Linn. (Coleoptera: Curculionidae) in maize hybrids. Karnataka Journal of Agricultural Sciences, 7(3):296-299; 8 ref

Kurdikeri MB, Aswathaiah B, Rajendraprasad S, Katgal RD, Aswathanarayana SC, 1993. Studies on relative seed damage - loss in weight and loss of viability caused by Sitophilus oryzae Linn. and Rhizopertha dominica Fabr. in maize hybrids. Seed Research, 21(2):72-77; 14 ref

Kuschel G, 1961. On problems of synonymy in the Sitophilus oryzae complex (30th contribution, Col., Curculionidea). Annals and Magazine of Natural History, Series 13(4):241-244

Letellier C, Haubruge E, Gaspar C, 1994. Importance of insect pests of stored cereals in Belgium. Parasitica, 50(1/2):81-88

Leuschner K, 1996. Methodology for screening sorghum resistance to storage pests. Drought-tolerant crops for southern Africa. Proceedings of the SADC/ICRISAT Regional Sorghum and Pearl Millet Workshop, Gaborone, Botswana, 25-29 July 1994., 173-179; 6 ref

Levchenko EA, Imshenetskii EI, 1984. Development of Sitophilus oryzae and S. granarius on the grain of some spring barley varieties. Nauchno-tekhnicheskii Byulleten' Vsesoyuznogo Selektsionno-geneticheskogo Instituta, No. 2:61-65

Levinson HZ, Levinson A, Ren Z, Mori K, 1990. Comparative olfactory perception of the aggregation pheromones of Sitophilus oryzae (L.), S. zeamais (Motsch.) and S. granarius (L.), as well as the stereoisomers of these pheromones. Journal of Applied Entomology, 110(2):203-213

Likhayo PW, Hodges RJ, 2000. Field monitoring Sitophilus zeamais and Sitophilus oryzae (Coleoptera: Curculionidae) using refuge and flight traps baited with synthetic pheromone and cracked wheat. Journal of Stored Products Research, 36(4):341-353; 17 ref

Longstaff BC, 1981. Biology of the grain pest species of the genus Sitophilus (Coleoptera: Curculionidae): a critical review. Protection Ecology, 3(2):83-130

Mahgoub SM, Ahmed SMS, 1996. Ricinus communis seed extract as protectants of wheat grains against the rice weevil Sitophilus oryzae L. Annals of Agricultural Science (Cairo), 41(1):483-491; 15 ref

Manueke J, Tulung M, Pelealu J, Pinontoan OR, 2015. DNA profile of Sitophilus oryzae and S. zeamais in rice and corn kernels. International Journal of ChemTech Research, 7(5):2194-2202. http://sphinxsai.com/2015/ch_vol7_no5/2/(2194-2202)V7N5.pdf

Matioli JC, 1981. Estimates of the damage caused in maize grain by the attack of Sitophilus oryzae (L., 1763) (Coleoptera: Curculionidae). Revista Brasileira de Armazenamento, 6:43-53

McMillian WW, Wiseman BR, Widstrom NW, 1981. An evaluation of selected sorghums for multiple pest resistance. Florida Entomologist, 64(1):198-199

Mishchenko AA, Malinin OA, Mashkei IA, Semernina EE, Rashkovan VM, Basteev AV, Bazima LA, Mazalov YuP, Kutovoi VA, 2000. High voltage technology for grain protection. Zashchita i Karantin Rastenii, No.1:38-39

Mohapatra S, Sawarkar SK, Patnaik HP, 1996. Comparative bioassay of different solvent extracts of neem seed kernels against Sitophilus oryzae, L. in rice. Current Agricultural Research, 9(1/2):89-93; 11 ref

Mould HA, 1973. Grain storage in Ghana. Ghana Cocoa Marketing Board, Accra. International Institute of Tropical Agriculture: A seminar on grain storage in the humid tropics, held in Ibadan, Nigeria, 26-30 July 1971. Tropical Stored Products Information, 25:44

Munyuli bin Mushambanyi T, 2003. The utilization of botanical dusts in the control of foodstuff storage insect pests in Kivu (Democratic Republic of Congo). (Effet de différentes poudres végétales sur l'infestation des semences de légumineuses et de céréales au cours de la conservation au Kivu (République démocratique du Congo).) Cahiers Agricultures, 12(1):23-31

Nakakita H, Ikenaga H, Shaaya E (ed. ); Bell-C, 1997. Action of low temperature on physiology of Sitophilus zeamais Motschulsky and Sitophilus oryzae (L.) (Coleoptera: Curculionidae) in rice storage. Ecologically safe alternatives for the control of stored-product insects. Papers from the XIII International Plant Protection Congress, July 1995, The Hague, The Netherlands. Journal of Stored Products Research, 33(1):31-38

Nelson SO, Bartley PG Jr. , Lawrence KC, 1997. RF and microwave dielectric properties of stored-grain insects and their implications for potential insect control. ASAE Annual International Meeting, Minneapolis, Minnesota, USA, 10-14 August, 1997. Paper American Society of Agricultural Engineers, No. 973072

Nelson SO, Bartley PGJr, Lawrence KC, 1998. RF and microwave dielectric properties of stored-grain insects and their implications for potential insect control. Transactions of the ASAE, 41(3):685-692; 22 ref

Ngamo TSL, Ngassoum MB, Mapongmestsem PM, Noudjou WF, Malaisse F, Haubruge E, Lognay G, Kouninki H, Hance T, 2007. Use of essential oils of aromatic plants as protectant of grains during storage. Agricultural Journal, 2(2):204-209. http://medwelljournals.com/fulltext/aj/2007/204-209.pdf

Olalquiaga FG, 1980. Phytosanitary features of Easter Island. Revista Chilena de Entomologia, 10:101-102

Omar EE, Kamel AH, 1980. Assessment of damage in some stored cereal grains due to insect attack. Bulletin de la Societe Entomologique d'Egypte, No. 63:119-127

Ovcharenko MM, Solodilov AI, Kravchuk MA, 2004. Treatment of pesticides in a weak electromagnetic field. Zashchita i Karantin Rastenii, No.3:42-43

Pantenius CU, 1988. Storage losses in traditional maize granaries in Togo. Insect Science and its Application, 9(6):725-735

Partridge IJ, 1973. The control of insects in stored maize. Fiji Agricultural Journal, 35(2):100-101

Pathak KA, Jha AN, 2003. Incidence of insect pests of stored maize and paddy in different storage structures/practices of north east region. Indian Journal of Entomology, 65(1):143-145

Phillips JK, Burkholder WE, 1981. Evidence for a male-produced aggregation pheromone in the rice weevil. Journal of Economic Entomology, 74(5):539-542

Pinto ARJr, Furiatti RS, Pereira PRVS, Lazzari FA, 1997. Evaluation of insecticides for control of Sitophilus oryzae (L.) (Coleoptera: Curculionidae), and Rhyzopertha dominica (Fab.) (Coleoptera: Bostrichidae) in stored rice. Anais da Sociedade Entomolo^acute~gica do Brasil, 26(2):285-290; 10 ref

Purrini K, 1976. On the insect fauna and their diseases in several old mills in Kosova County, Yugoslavia. Acta Phytopathologica Academiae Scientiarum Hungaricp, 11(3-4):305-315

Rajendran S, Gunasekaran N, Muralidharan N, 2001. Studies on phosphine fumigation of wheat bag-stacks under different storage conditions for controlling phosphine - resistant insects. Pesticide Research Journal, 13(1):42-47

Rajkumar R, Anitha TN, 1998. Evaluation of the efficacy of 'stored grain insect trap'. Entomon, 23(3):227-231; 18 ref

Ramputh A, Teshome A, Bergvinson DJ, Nozzolillo C, Arnason JT, 1999. Soluble phenolic content as an indicator of sorghum grain resistance to Sitophilus oryzae (Coleoptera: Curculionidae). Journal of Stored Products Research, 35(1):57-64; 8 ref

Revetti LM, 1972. Irradiation of grains. I. Irradiation of maize (Zea mays l.). Agronomia Tropical, 22(5):497-507

Riudavets J, Lucas É, Pons MJ, 2002. Insects and mites of stored products in the northeast of Spain. Bulletin OILB/SROP [Proceedings of the IOBC/WPRS Working Group "Integrated Protection in Stored Products", Lisbon, Portugal, 3-5 September, 2001.], 25(3):41-44

Rodriguez RR, 1976. Determinacion del dano causado por plagas de almacen a variedades de maiz en Yucatan. Agricultura Tecnica en Mexico, 3:442-446

Rubbi SF, Begum SS, 1986. Effect of insect infestation on stored IRRI-8 paddy. Bangladesh Journal of Zoology, 14(2):181-182

Saravanan L, Gujar GT, 2006. Distribution of Bacillus thuringiensis Berliner in samples from warehouse and insect cadavers. Journal of Entomological Research, 30(1):25-28

Seifelnasr YE, 1991. Suweba (mud bin) storage of grains in the Sudan. Indian Journal of Entomology, 53(3):494-502

Sharma PR, Thappa RK, Tikku K, Chand D, Saxena BP, 1997. Control of stored-product moths and beetles by suboptimum temperatures. Tropical Science, 37(1):28-34; 10 ref

Sharma RK, 1999. Efficacy of neem products against storage pests in maize. Annals of Agricultural Research, 20(2):198-201

Shazali MEH, 1987. Weight loss caused by development of Sitophilus oryzae (L.) and Sitotroga cerealella (Oliv.) in sorghum grains of two size classes. Journal of Stored Products Research, 23(4):233-238

Singh B, Kumar R, Katiyar RR, 1998. Development of rice weevil, Sitophilus oryzae Linn. on grain of different varieties of maize. Annals of Plant Protection Sciences, 6(1):70-74

Singh DK, Singh B, Singh YP, Pandey ND, Malik YP, 1991. Relative resistance of some barley varieties to rice weevil, Sitophilus oryzae Linn. Indian Journal of Entomology, 53(2):280-285

Singh HN, Mathew G, 1973. Comparative resistance of different wheat varieties (to rice weevil Sitophilus oryzae Linn.) during storage. Mysore Journal of Agricultural Sciences, 7(1):86-89

Singh SR, Benazet J, 1975. Chemical intervention on all stages and on all scales of tropical storage practice. Brady, E. U.; Brower, J. H.; Hunter, P. E.; Jay, E. G.; Lum, P. T. M.; Lund, H. O.; Mullen, M. A.; Davis, R. (Organisers): Proceedings of the First International Working Conference on Stored-Product Entomology, Savannah, Georgia, USA, October 7-11, 1974. Stored-Product Insects Research and Development Laboratory, ARS, USDA & Department of Entomology, Georgia University. Savannah & Athens, Georgia USA, 41-46

Sittisuang P, Imura O, 1987. Damage of rough and brown rice by four stored-product insect species. Applied Entomology and Zoology, 22(4):585-593

Squire FA, 1972. Storage and household pests. In: Squire FA, ed. Entomological Problems in Bolivia. PANS, 18:261

Srinivasacharayulu BS, Yadav TD, 1997. Toxicity of insecticides against Sitophilus zeamais and S. oryzae. Indian Journal of Entomology, 59(2):190-192

Stejskal V, Kucerová Z, Luká? J, 2004. Evidence and symptoms of pasta infestation by Sitophilus oryzae (Curculionidae; Coleoptera) in the Czech Republic. Plant Protection Science, 40(3):107-111

Stusak JM, Verner PH, Viet Tung N, 1986. A contribution to the study of store pests in Vietnam. Agricultura Tropica et Subtropica, 19:131-141

Suss L, Locatelli DP, Cavalieri M, 1997. Valutazione dell'attivita di estratti di Azadirachta indica A. Juss su insetti delle derrate. Tecnica Molitoria, 48(10):1105-1112

Szeoke K, 1989. The occurrence of the maize weevil (Sitophilus zeamais Motsch.) in Hungary. Novenyvedelem, 25(4):162-166

Thakur AK, 1999. Screening of rice varieties against some stored grain pests. Insect Environment, 4(4):140-141

Thakur AK, Sharma JK, 1996. Assessment of storage losses in rice in Himachal Pradesh. Pest Management and Economic Zoology, 4(1/2):97-100; 5 ref

Thind BB, Muggleton J, 1981. Inheritance of the ability of strains of Sitophilus oryzae (L.) (Coleoptera: Curculionidae) to breed on split-pea (Pisum sativum). Bulletin of Entomological Research, 71(3):419-424

Tilley DR, Langemeier MR, Casada ME, Arthur FH, 2007. Cost and risk analysis of heat and chemical treatments. Journal of Economic Entomology, 100(2):604-612. http://www.bioone.org/doi/full/10.1603/0022-0493%282007%29100%5B604%3ACARAOH%5D2.0.CO%3B2

Torres JB, Saavedra JLD, Zanuncio JC, Waquil JM, 1996. Resistance of sorghum to Sitophilus oryzae (L.) and its association with varietal parameters. International Journal of Pest Management, 42(4):277-280; 23 ref

Trematerra P, 1998. Capture of stored-grain Coleoptera with WB probe II trap: influence of grain type. Anzeiger fur Schadlingskunde, Pflanzenschutz, Umweltschutz, 71(7):135-137

Trematerra P, Fontana F, Mancini M, 1996. Analysis of development rates of Sitophilus oryzae (L.) in five cereals of the genus Triticum. Journal of Stored Products Research, 32:315-322

Trematerra P, Fontana F, Mancini M, Sciarretta A, 1999. Influence of intact and damaged cereal kernels on the behaviour of rice weevil, Sitophilus oryzae (L.) (Coleoptera: Curculionidae). Journal of Stored Products Research, 35(3):265-276; 35 ref

Trematerra P, Gentile P, Djikoloum T, 2003. Cereal storage in developing countries: Chad case history. Tecnica Molitoria International, 54(2):155-163

Trematerra P, Girgenti P, 1989. Influence of pheromone and food attractants on trapping of Sitophilus oryzae (L.) (Col., Curculionidae): a new trap. Journal of Applied Entomology, 108(1):12-20

Trematerra P, Lanzotti V, 1999. The activity of some compounds extracts by Allium on stored-product insects Oryzaephilus surinamensis (L.), Sitophilus oryzae (L.) and Tribolium castaneum (Herbst). Anzeiger fu^umlaut~r Scha^umlaut~dlingskunde, 72(5):122-125; 27 ref

Trivelli H dell'Orto, Dell'Orto Trivelli H, 1975. Species of insects attacking different types of stored wheat and their control. Proceedings of the First International Working Conference on Stored-Product Entomology, Savannah, Georgia, USA, October 7-11, 1974. Savannah & Athens, Georgia, USA: Stored Product Insects Research and Development Laboratory, ARS, USDA & Department of Entomology, Georgia University, 219-233

Virmani SS, 1980. Varietal resistance to rice diseases and insects in Liberia. International Rice Research Newsletter, 5(2):3-4

Visalakshi Mahanthi, Gour TB, Ramulu MS, 2005. Relative abundance of stored grain pests in maize. Journal of Research ANGRAU, 33(4):96-102

Wakefield ME, 1998. The effet of insect age on the response of three species of Sitophilus to 4S, 5R-sitophilure and food volatiles. Proceedings of the 7th International Working Conference on Stored-product Protection, 2:1513-1518

Weaver DK, Dunkel FV, Ntezurubanza L, Jackson LL, Stock DT, 1991. The efficacy of linalool, a major component of freshly-milled Ocimum canum Sims (Lamiaceae), for protection against postharvest damage by certain stored product Coleoptera. Journal of Stored Products Research, 27(4):213-220

Wongo LE, Pedersen JR, 1990. Effect of threshing different sorghum cultivars on Sitotroga cerealella (Oliv.) and Sitophilus oryzae (L.) (Lepidoptera: Gelechiidae and Coleoptera: Curculionidae). Journal of Stored Products Research, 26(2):89-96

Yana A, 1969. On the use of iodofenphos to control some grain insects in Tunisia. Documents Techniques, Institut National de la Recherche Agronomique de Tunisie, No. 43:1-19

Yoon TaeJoong, Ryoo MunIl, Cho HyeWon, 1997. A generalization of the matrix model of rice weevil population (Coleoptera: Curculionidae) and its applicability. Korean Journal of Applied Entomology, 36(3):215-223; 28 ref

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