Volume 2, Number 2, July-December 2014

INCIDENCE OF INSECT PESTS IN SOME STORED CROPS IN SINGU TOWNSHIP, MANDALAY REGION

Dr. Nwe Nwe San Department of Zoology, Yadanabon University, Myanmar

ABSTRACT Sitophilus or yzae w as f ound to be t he most f ecund species i n all A s urvey on t he i ncidence of cereals t ested, and Tribolium c asta- insect pe sts i n s tored c rops i n Singu neum w as t he l east f ecund. T he Township, M andalay R egion was largest popul ation of S itophilus oryzae conducted from June, 2013 to March, (354 adults) w as r ecorded i n w heat. 2014. However, the largest population of R. Seven s pecies o f b eetles: dominica ( 107 a dults) was r ecorded Sitophilus or yzae, S . granarius, in Pawsanhmwe. Tribolium c astaneum, R hizopertha Mean percentage g rain d amage dominica, O ryzaephilus surinamensis, and weight losses caused by the pests Callosobruchus maculatus, and Acan- were 64.38 and 56.60%, respectively. thoscelides obt ectus be longing t o The m aximum d amage an d weight Order Coleoptera a nd one s pecies o f loss w as c aused by S . or yzae. Grain moth: S itotroga c erealella b elonging damage ranged f rom 54 t o 73% to Order L epidoptera w ere r ecorded. between three t o six m onths of S oryzae and S . granaria were found storage w hereas t he w eight loss in r ice, w heat, m aize, an d cereals; varied from 45 to 70%. Rhyzopertha dominica in rice, maize, and cowpea; Oryzaephilus surinamensis in r ice and s esame; Tribolium c asta- neum i n r ice, w heat, an d m aize; KEYWORDS Callosobruchus maculates in rice and Incidence, Insects pests, stored crops, various pulses; A canthoscelides ob - Sigu Township, Mandalay Region tectus in cowpea and lablab bean; and Sitotroga cerealella in stored sesame. Among t he r ecorded insects, INTRODUCTION Sitophilus s pecies a nd C . maculates Insects are f ound in a ll t ypes were f ound t o be t he m ost abundant of environment and they occupy little and s erious pe st of pul se c rops. more t han two t hirds of t he known Sitotroga species was found to be the species of a nimals in t he w orld. least abundant an d is r egarded as Insects affect h uman beings i n a minor pest. number of ways. Many o f t hem f ed 90 Volume 2, Number 2, July-December 2014 on all ki nds of pl ants i ncluding crop scientists w ere r ecruited to th is end plants, f orest trees, me dicinal plants by t he va rious m inistries of a gri- and weeds. They also infest the food culture. Seed g rain ha s to be s tored and ot her s tored pr oducts i n until th e s tart of t he ne xt g rowing godowns, bins, storage structures and season, 6 -8 m onths on a verage. packages causing hug e a mount of Therefore t he average am ount of loss t o the s tored food a nd also cereal g rain i n storage i n t he world deterioration of food quality (Bhatia, must be ha lf the pr oduction, or 900 1978). million tons. T hree br oad c ategories Cereal g rains are t he most according t o the t ype of pr oduce are (a) p lant ma terials, for ex amples; important c rop produce i n storage. The f ood a nd A griculture cereals, pulses, nut s, dried f ruits, oi l Organization ( FAO) of t he U nited seeds, be verages a nd s pices, f ruits, Nations e stimated t hat a bout 20 vegetables, roots and tubers, etc.; (b) percent losses ar e d ue to i nsects an d animal materials, for example: meats, rodents i n w orldwide ( Hill, 1990) . game an imals, meat products, f ish, Different figures showed that ten per mollusks, e tc. and ( c) s tructural cent l osses w ere r ecorded i n Europe timbers, packaging materials. Among and 30 pe rcent in A sia a nd Africa. three c ategories of pr oduce, pl ant FAO also es timated t hat p reharvest materials were especially emphasized losses i n de veloping c ountries w ere for this study. around 40 pe rcent w hile pos tharvest The majority of stores are for losses a dded a f urther 10 t o 20 flours a nd grains, e specially for percent (Yudelman e t al., 1998) . I n cereal grains. When flours and cereal terms of value, the global production grains are stored, various pest species of f our cer eal g rains s uch as r ice, attack on t he s tored pr oduce. T hese wheat, barb b arley, an d m aize w as pests i nclude Tribolium castaneum, about US$ 228.7 billion a nd l osses T.confusum, Sitophilus, Acanthoselides, due to insect pests was about US$ 68 Rhizopertha, Sitotroga, Ephestia, billion annually (Oerke et al., 1995). food m ites, a nd various ot her insect Worldwide annual losses in store has pests. On t he basis of f eeding been given as 10% of all stored grains, behaviour, and t o a l esser e xtent t he i.e., 13 million tons of grain losses due type of da mage, t he s tored pr oduce to insects or 100 million tons to failure pests can b e classified as p rimary to s tore prope rly (Y udelman e t al., pest, secondary pests, fungus feeders, 1998). The i nitial i nfestation of i nsect scavengers, specialized p lant f eeders may s tart either in t he f ield or i n the and f eeders of an imal materials. store. Primary pests ar e ab le t o p enetrate Hill ( 1990) m entioned that the in tact p rotective te sta o f grains more attention w as being g iven t o and s eeds, and s o they a re of stored produce pests by the 1960s and 91 Volume 2, Number 2, July-December 2014 particular importance an d es pecially - to s tudy insect pe sts damaging. incidence i n stored c rops in Singu Township. Hill (1990) mentioned that the - to obs erve the f ood secondary pest ar e o nly able t o f eed preference of some insect pests an damaged g rains an d s eeds, w here on rice and wheat. the testa is cracked, holed, abraded or - to obs erve the f ood otherwise broken, e ither by phy sical preference of some insect pests damage d uring ha rvesting, or by too on l ablab bean, bl ack gramand rapid dr ying, or by t he pr ior feeding cowpea. of a pr imary pest. S ome of the - to obs erve t he population secondary pests include the larvae of growth of some pests on maize. Ephestia, Plodia, and t he beetles - to determined t he per- Oryzaephilus, Cryptolestes, Tribolium centage weight loss of grain and and the other Tenebrionidae. percentage o f insect damaged Among stored pr oduce, r ice grain. grain is one of the major cereal crops of t he tropical i ncluding Myanmar, sub-tropical, a nd s ome ot her countries MATERIALS AND METHODS for storage. It is a primary staple food for 60 pe rcent of the popul ation of Study Site Singu i s s ituated a t 22°32´ the World. R ice pr oduction r eached 42.86" N 95°59´ 26.98" E a nd to m aximum l evel a mounting 1148 bounded by the Ayerawaddy River in million t ons i n Myanmar i n 2003- the west, Naunghkio Township in the 2004. P ulses a re m ajor s ource of east, Tha Paik Kynn Township in the protein, e nergy, minerals a nd vitamins. north, a nd t he M adaya T ownship i n Among di fferent va rieties of pulses, the south. T he S ingu T ownship i s green gram an d b lack gram ar e t he situated 93.33km f rom nor th of most important for local consumption Mandalay, 82.7 m above t he sea and export i n M yanmar. It i s n eeded level. The f ive b rokers’ s ale cen tre to study s tored pr oduct i nsect pe sts were s elected t o co nduct t he p resent because o f t heir s evere d amaging on work, na mely; A ung T hikedi, stored grains or flours. Kyipyar, M yint Wai, M oe Myint Kyal, a nd T hein K yaw S oe from Singu Township, Mandalay Region.

OBJECTIVES OF THE STUDY Study Period The p resent r esearch w as Therefore, t his s tudy was conducted from June, 2013 to March, carried out w ith t he f ollowing 2014. objectives: 92 Volume 2, Number 2, July-December 2014

Collection of Host Species Identification of Insect Pests Ten kilograms of t wo r ice Identification was made using varieties ( Manawthukha a nd P awsan combination o f in sect id entification hmwe) w ere co llected f rom local keys, pi ctures, c omparison w ith a lready broker’s sale centers of Singu for this identified s pecimens’ i n laboratory, experiment. S imilarly th e s ame and descriptions. The specimens were amount o f m aize was co llected from recorded with t he D igital S ony market, co mmon w heat, sesames, camera a nd 400, 800 U SB m icro wild ol ive, l ablab be an; c ow pea, captures. A ll collected s pecimens black g ram, a nd pigeon pe a were were identified us ing ke ys ba sed on purchased from t he sale centers. The Borror a nd W hite, 1970; B orror and samples were obtained from as many Delong, 1990; H aines', 1991, and different pa rts of t he va rious s torage other available references were used. facilities a s p ossible ( top, sides, centre, and bottom). Each sample was Insect Rearing put in a pa per bag a nd l abeled w ith Each of one hundred grams of the necessary i nformation. T he seeds ( rice, m aize, an d w heat) was samples o btained f rom t he s ame randomly taken from ten kilogram of storage w ere mixed t ogether and seeds and weighed by using a digital placed i n a c loth bag f or further balance in the laboratory, Department inspection i n l aboratory a s pe r t he of Z oology, Y adanabon U niversity. methods us ed by F iridissa (1999). The weighed seeds were put into each Inspection o f t he s amples w as made clean bottle ( 5 cm d iameter an d 1 0 within two weeks of collection in the cm i n he ight) a nd c overed w ith l ids. laboratory of Department of Zoology, About 20 uns exed a dult insects: Yadanabon U niversity (Figure 1, Sitophilus oryzae, Tribolium castameum Figure 2). or Rhyzopertha dominica of t he insect s pecies w ere s eparately Collection of Insect Pests introduced i nto t he bot tles A fter 10 In t he l aboratory, D epartment days of ovi position, all a dult insects of Z oology, e ach s ample of r ice a nd of t he i nsects w ere r emoved. E ach stored crops were sieved over a 2 mm bottle w here the a dult insects mesh s ieve ( Abraham, 1995) a nd all oviposited w as ke pt f or pr ogeny fractions w ere ex amined. Insects emergence. P rogeny em ergence was were r emoved, counted a nd grouped monitored da ily and t hose emerged according to or der, family, a nd w ere on t he s ame d ay w ere t ransferred to preserved dry as pinned collections or fresh g rain i n bot tles. with l ids and in 75% e thanol f or i dentification kept a t the e xperimental conditions (Figure 3). until sufficient num ber of s uch insects were obt ained. Each bot tle containing one hundr ed g rams of chosen seeds ( rice, maize, w heat o r 93 Volume 2, Number 2, July-December 2014 pulses) and i nsects was s ealed b y Data Calculation using m uslin c loth a nd r ubber rings. Sampled g rains w ere separated Experiment w as c onducted in t hree into damaged a nd unda maged, replicates (Figure 4, F igure 5, Figure weighed, num bers counted a nd 6, Figure 7). percentage weight l osses d etermined using the f ormula of A dams a nd Schulter (1978) as follows:

% weight loss = ((U Nd - DNu) /U (Nd + Nu) × 100

U is w eight of unda maged damaged and un-damaged grains was grain, Nd i s number of da maged observed using a ha nd lens f or t he grain, D is weight of damaged grain, presence of hole or burrow. and Nu i s number of unda maged The p ercentage o f insect grain. Insect damage was assessed by damaged s eed w as t hen calculated the count method. One hundred seeds (Fekadu e t a l., 2000, Wambugu e t were r andomly t aken from e ach al., 2009) as follows: sample a nd the number of i nsect

Insect Damaged grain(%) = ( Number of insect damaged grain) x 100 Total number of grain

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Oryza sativa var: (Manawthukha) Oryza sativa var: (Pawsan hmwe)

Oryza sativa var: (Manawthukha) Oryza sativa var: (Pawsan hmwe)

Triticum vulgare (Common wheat) Sesamum indicum (Sesame)

Sorghum dochna var: burmanicum(White-Broom corn)

Figure 1. Grain 1

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Dolichos lablab (Lablab bean) Vigna catjang (Cow pea)

Cajanus indicus (Pigeon pea) Putranjiva roxburghii (Wild olive)

Phaseolus mungo (Black gram)

Figure 2. Grain 2

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Sitophilus oryzae Sitophilus granaries

Tribolium castaneum Rhyzopertha dominica

Oryzaephilus surinamensis Callosobruchus maculates

Acanthoscelides obtectus Sitotroga cerealella

Figure 3. Species of beetles

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Figure 4. The population growth of Stiophilus sp, Tribolium sp, and Rhyzopertha sp in Pawsanhmwe rice during a 22-week study period

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Figure 5. The population growth of Stiophilus sp, Tribolium sp, and Rhyzopertha sp in Manawthukha rice during a 22-week study period

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Figure 6. The population growth of Sitophilus sp, Tribolium sp, and Rhyzopertha sp in Wheat during a 22-week study period

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Figure 7. The population growth of some Callosobruchus sp beetles in some pulses rice during a 22-week study period

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RESULTS wild-olive. Acanthoscelides was Eight species o f i nsect p ests recorded f rom c owpea a nd lablab were r ecorded f rom t his study bean. Sitotroga was r ecorded f rom conducted in S ingu T ownship, sesame (Table, 2). Mandalay Region from June, 2013 t o Mean popul ation de nsity of March, 2014. A mong t hem, Sitophilus oryzae (65.78 a dults) w as Sitophilus oryzae, S. granarius, the highest a mong t he s tored c rop Tribolium castaneum, Rhizopertha insect p ests and S. granarius (45.26 dominica, Oryzaephilus surinamensis, adults) w as t he s econd hi ghest a nd Callosobruchus maculates, and Acan- Sitotroga cerealella (4.23 adults) was thoscelides obtectus belong t o Order lowest a mong t he s tored c rop i nsect Coleoptera and one species, Sitotroga pests (Table, 3). cerealella, be long to O rder Lepid- optera Mean p ercentage g rain damage an d w eight losses cau sed by All stored grains tested in this the pe sts w ere 64.38 a nd 56.60%, study were infested with insect pests. respectively. T he m aximum damage The s ystematic p osition o f s ome and weight l oss w as c aused by insect pests of stored crops and their S.oryzae. Grain d amage r anged from status from S ingu T ownship, M an- 54 t o 73% be tween three t o six dalay Region (Table, 1) and Number months of storage whereas the weight of insects recorded from some stored loss varied from 45 t o 70%. More of products of Singu Township, Manda- the n umber of w eevils associated lay Region (Table, 2) were described. with stored g rains at each s ite w as associated with more number of grain damage an d w eight losses. As t he THE INCIDENCE OF INSECT length of s torage pe riod i ncreased, PESTS AND THEIR PREFERENCE the damage and losses also increased. IN STORED CROPS Sitophilus oryzae was f ound Sitophilus oryzae and S. to be t he most f ecund species i n all granarius were r ecorded f rom a cereals tested, and T. castaneum was variety of s tored crops m ainly rice, the l east. T he largest popul ation of wheat, and m aizae, b lack g ram, S.oryzae (372 adults) was recorded in cowpea, and pigeon pea. Rhizopertha wheat. H owever, t he l argest population was also r ecorded f rom t hree hos t of R.dominica (106 a dults) w as materials, r ice, m aize, an d cowpea. recorded i n P awsanhmwe f rom a n Oryzaephilus was recorded from rice initial population adults. and s esame. Tribolium was r ecorded Callosobruchus species w as from t hese s tored c rops m ainly f rom found t o be t he hi ghest ( 223 adults) rice, w heat, and m aize. Callosobruchus in lablab bean and it was higher than was r ecorded f rom b lack gram, black gram an d co wpea. T he cowpea, pigeon pea, lablab bean, and 102 Volume 2, Number 2, July-December 2014 populations i n t he l atter t wo pulses different from each other. (146 a nd 104 a dults) were not

Table 1. The systematic position of some insect pests of stored crops and their status from Singu Township, Mandalay Region.

Order Family Scientific Name Common Status Host Name Coleoptera Curculionidae Curculionidae Rice Primary Rice Sitophilus oryzae weevil pest Sitophilus Granary Primary Rice granarius Weevil pest Tenebrionidae Tribolium Red rust Secondary Maize, castaneum flour beetle pest black gram Bostrichidae Rhizopertha Lesser Secondary Maize, dominica grain borer pest cowpea Silvanidae Oryzaephilus Saw Secondary Rice, surinamensis toothed pest sesame grain beetle Bruchidae Callosobruchus Southern Primary Cowpea, maculates cowpea pest pigeon weevil pea Chrysomelidae Acanthoscelides Bean Primary Cowpea, obtectus weevil pest lablab bean, wild-olive Lepidoptera Gelechidae Sitotroga cerealella Angoumois Primary Sesame grain moth pest Source: Original Research

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Table 2. Mean number of the primary insect pests of maize recorded from maize grain samples in Singu Township, Mandalay Region.

Insect pests Number of maize Mean number of maize per store grains with 100 g of the pest seed (mean ± SD) Sitophilus oryzae 100 65.78±4.53 S. granarius 100 45.26±3.12 Tribolium castaneum 100 9.09±2.11 Rhizopertha dominica 100 5.27±0.95 Oryzaephilus 100 7.12±1.45 surinamensis Callosobruchus 100 6.04±0.97 maculates Acanthoscelides obtectus 100 11.34±3.12 Sitotroga cerealella 100 4.23±0.78 Source: Original Research

Table 3. Percentage grain damage and weight losses of stored crop grain at different site(Singu) three to six months after storage (n = 100).

Host stored crops species Grain damage (%) Weight loss (%) Oryza sativa var: 73.25 ± 1.48 69.33 Oryza sativa var: 64.50 ± 0.50 50.67 Triticum vulgare 54.67 ± 0.47 45.33 Sesamum indicum 63.75 ± 0.83 57.33 Sorghum dochna var: 72.75 ± 1.48 70.67 Dolichos lablab 55.50 ± 0.50 45.67 Vigna catjang 61.50 ± 0.50 56.67 Cajanus indicus 57.50 ±0.50 48.33 Putranjiva roxburghii 72.00 ±1.58 65.33 Phaseolus mungo 68.33 ± 1.24 56.67 Range 54 to 73 45 to 70

Source: Original Research

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DISCUSSION from only i nsect pe st s pecies, not found in Tribolium castaneum. The p resent study on t he incidence of i nsect pe sts on stored Among t he hos ts, M aize crops from S ingu T ownship, (Triticum vulgare) t wo species o f Mandalay R egion co mmenced from insect p est Sitophilus sp: a nd June 2013 t ill March 2014. The Tribolium sp; w ere r ecorded. K hin present study w hich i nvolved ni ne Thel Marr ( 2005) recorded onl y one brokers’ s ale centers s ituated around species Sitophilus sp;, how ever s he Singu T ownship. A lthough nine did not record Tribolium casta-neum. brokers’ s ale centers w ere explored, Hill ( 1990) reported t hat rice only five centers, Aung Thikedi, Kyi weevil Sitophilus oryzae is one of the Pyar, Myint W ai, Moe M yint K yal, most d estructive primary p ests of and Thein Kyaw Soe were chosen for stored g rain w orldwide including detailed study. Myanmar a nd i s ve ry i mportant a nd In t he pr esent s tudy on the very damaging. insect pest eight species belonging to Hill ( 1990) r eported t hat the two orders, seven families, and seven population of Oryzaephilus genera w ere r ecorded. S even species surinamensis was f ound to be t he of i nsect p ests w ere r ecorded order lowest am ong t he s torage pests. Coleoptera a nd one s pecies of order However i n t he pr esent s tudy this Lepidoptera. species was co llected from r ice an d Rice, wheat, m aize, an d sesame (7.12 adults) was recorded as sesame w ere p urchased f rom Moe the third l owest a mong t he s tored Myint Kyal and Thein Kyaw Soe sale crop insect pests, of this study it can centers; l ablab b ean and b lack gram be as sumed t hat Oryzaephilus were p urchased f rom K yi Pyar; surinamensis is not an i mportant s tored cowpea, pigeon pe a, and w ild ol ive product pe st i n S ingu Township, were purchased from Myint Wai sale Mandalay Region. center and Aung Thikedi center. Capable of infesting all cereal Among the hosts, five species grains but recorded as favouring rice of i nsect p est w ere r ecorded K hin and w heat, a nd other s mall grains, Thel M arr ( 2005) a lso r ecorded f our flour, posta, and other cereal products insect p est s pecies, f rom r ice b ut (Hill,1990). P rimary hos ts of both Callosobruchus sp: was not included weevils ar e O ryza sativa (rice), Zea in her work. mays (maize), Triticum (wheats), Stroed pr oducts ( dried stored Among t he hos ts, w heat products), and sorghum. (Triticum vulgare) ha s be en found two species of insect pest which was Hill ( 1990) r eported that described by K hin T hel M arr (2005) Sitophilus oryzae is r ecorded t o be

105 Volume 2, Number 2, July-December 2014 the dom inant one i n t he E astern food stuffs w orldwide i ncluding Highlands of E thiopia a nd it i s ve ry Myanmar R.dominica is also primary common on m aize, w heat a nd stored grain pe st. I t can be r ecorded sorghum. I n S outh E ast A sia a nd occasionally i nfesting r ipe cer eals in China t he presence o f S.oryzae the f ield. L arval in festation in itially weevils i s expected an d tolerate t o a leaves no vi sible s ymptoms on the large extent, but in adults (and pupae grains b ecause l arval d evelopment inside g rains) can af fect serious occurs within a single grain. reduction in value. According t o Emana & Hill (1990) r eported t hat a Assefa (1998), Sitotroga cerealella is number of di fferent i nsect ( both a s erious p rimary pest th at mainly beetles an d m oth l arvae) an d al so attacks m aize, wheat a nd sorghum, some m ites show a feeding both in t he f ield and i n s tores. T he preference fo r the g erm (embryo) present s tudy in S ingu Township region of seeds and grains. revealed t hat t his pe st w as f ound i n sesame w hich w as r esponsible for Hill (1990) poi nted out t hat 63.75 a nd 57.33 percentage of grain some of primary pests species show a damage and weight loss respectively. preference f or f eeding o n t he germinal r egion of t he s eed a nd s o From t he a bove obs ervation, they are r esponsible f or a l oss of it w as f ound that Sitophilus oryzae quality and nut ritive va lue i n c ereal was t he m ost s erious p est s pecies in grains f or f ood, a nd a l oss of cereals and its largest population was germination a bility o f s eeds. S ome in wheat. examples o f p rimary p ests ar e the larvae o f Sitotroga, the a dults a nd larvae o f Sitophilus, Rhizopertha, ACKNOWLEDGEMENTS Trogoderma and Callosobruchus, etc. and of course rats and mice. We ar e d eeply grateful to Rector D r. Khin M g Oo a nd P ro- There w ere o ther p ests and Rector D r. M aung M aung N aing, also be neficial hy menopterans of Yadanabon University, f or t heir concern y et not pr eserved and permission to work on this research. identified in the current study. These insects a nd noni nsect pe sts appeared We are greatly indebted to Dr. to be l ess i mportant, l ess abundant Khin M ay Nyo, P rofessor, H ead of and difficult to collect and thus, were Department of Zoology, Y adanabon not r ecorded b ecause t hey ap pear t o University, f or he r a dvice in th is be of no importance as direct pests. work.

Adams and S chulter ( 1978) stated that Rhizopertha dominica is a serious pest of stored grains and other 106 Volume 2, Number 2, July-December 2014

BIBLIOGRAPHY Haines, C.P. (Editor), 1991. Insects and arachnids of tropical Abraham, T., 1995. Insects and other stored products: their biology arthropods recorded from and identification (a training stored maize in western manual). Chatham, UK; Ethiopia. ACSL 4(3):339-343. Natural Resources Institute, Adams, J.M. and Schulter, G.M., Ed. 2:vi+246 pp. 1978. Losses Caused by Harris K.L. and Lindblad C.G. (eds), Insects, Mites and Micro- New York, American organisms. In: Postharvest Association of Cereal Grain Loss Assessment Chemists. Methods. pp. 83-95. Hill, D.S., 1975. Agricultural insect Bhatia, S.K. and Nadarajan, L., 1978. pests of the tropics and their Inheritance of black body control. Agricultural insect colour in a mutant of pests of the tropics and their Tribolium castaneum (Herbst) control. Cambridge University with notes on its biology. Press. Cambridge UK, 516 pp. Journal of Entomological Hill, D.S., 1990. Pests of stored Research, 2 (2) : 219-221 products and their control. Borror, Donald J., and Dwight London, UK; Belhaven Press, Delong, M., (1990) (7th ed.). 274 pp. An introduction to the study of Khin Thel Marr, 2005. The natural insects. New York: Holt, incidence of insect pests in Rinehart and Winston. some stored products in Borror, Donald J., and White, R. E., Mandalay Environs. MRes. (1970). A field guide to Thesis, Department of Orthoptera of North America. Zoology, Yadanabon Boston: Houghton Mifflin, University. 368 pp.; illus. Oerke, E.E, Dehne, W.H., Emana, L., Geremew, B., Waktola, Schohbeck, F., and Weber, A., W., 1998. Quality of grain 1995. Crop production and sorghum (Sorghum bicolor crop protection: Estimated (L.) Moench) stored in losses in major food and cash traditional underground pits: crops. Journal of the Kansas Case studies in two agro- Entomological Society, climatic zones in Hararghe, 65:311-349. Ethiopia. JFST 37(3):238-244. Firdissa, E., 1999. Insect pests of Farm-stored Sorghum in the Bako Area. PMJE 3 (1&2):53-60. Girma D, Tadele T.

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