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.