Section 12 - Country presentation

Contents - Previous - Next

On farm storage, pest control, drying and prevention of mycotoxins in Bangladesh
Integrated pest management strategies in grain storage systems in Myanmar
Management of grain storage in the republic of Korea
Farm level grain storage pest management in Nepal
Public sector storage of wheat in Pakistan and the associated problem of insect pests
The current storage pest problems and their management in the Philippines
Pest control methods adopted for preservation of grain in Sri Lanka
Activities of the post harvest technology working group on insect pest management research in grain storage in chiang mai university northern Thailand
Survey of stored insect in rice field before harvest
Present situation and experience in the socialist republic of Vietnam on pest management



On farm storage, pest control, drying and prevention of mycotoxins in Bangladesh

Nazrul Islam
Tapan Kumar Dey


Bangladesh is predominantly an agricultural country with more than 80% of its people engaged in agriculture. Beset with the problems of a huge population to support and relatively a small area available for cultivation, this country faces the problem of chronic food shortages to the tune of 2.0-3.0 million tons every year.

The Government has already embarked upon projects to minimise this food deficit within the shortest possible time. It is imperative that efforts of increasing food production should be more directed towards finding ways and means to increase the production per unit area of cultivated land available. Total demand for grains in Bangladesh is 16.5 million tons while production is 15.2 million tons with net production of 13.7 million tons (production of food grains-losses and seeds (15.2-1.5 = 13.7 million tons). This food deficit is 2.8 million tons. This shortfall is met by the Government by imports through food aid, purchases, grants etc.

Imports and procurements from domestic sources amount to only 15% of the total requirement of food grains which is administered by the Government through the Ministry of Food. The rest (85%) is stored, handled and distributed by the private sector at farmers traders and millers levels.

Off-farm storage

Total volume of off-farm storage is approximately 1.8 million tons of which bag and bulk storage are 1.58 and .28 million tons respectively. Internal procurement is 0.5 million ton and external procurement is 1.8 million tons. This quantity (2.3 million tons) is stored and maintained in 4 silos and 1012 C.S.D. (Central Storage Depots), L.S.D. (Local Storage Depots) and TPC (Temporary Purchase Centre). Capacity of 4 silos is 0.25 million ton. They are generally used for bulk storage as transit depots for imported grains.

Types of godowns, numbers and capacities are given below:

Type No. Capacity (million tons)
C.S.D. 12 0.45
L.S.D. 600 1.00
T.P.C. 400 0.10


The aforesaid types of godowns are used for bag storage of grains imported and locally produced. In Bangladesh mainly paddy and wheat are stored in silos, and godowns are both used for both internal purchase and imported grain and seeds of pulses and oilseeds are stored only when those commodities are imported.

Pests occuring in food-godowns

Pests occuring in food-godowns are categorized by following types:

Pest Slightly important Important Very important
Fungus, Bacteria     *
Mites, Psocids *    
Birds   *  
Rodents     *
Insects     *


The Ministry of Food and Department of Food have given priority only to insect pest damage. Mojor storage insects in Bangladesh are rice weevil,Sitophilous oryzae (Linnaeus), lesser grain borerRhizopertha dominica (Fabius), rice meal mothCorcyra cephalonica (Stainton), Angoumlis grain mothSitotroga cerealella (OIivier), red flour beetle-Tribolium castaneum (Herbs"), flat grain beetle-Laemophloeus oninutus (Olivier), saw toothed grain beetleOryazephilus surinamensis (Linnaeus) pulse beetleCallo sobruchus chinensis (Linnaeus), flour or grain mite and psocids.

Important storage moulds are-Aspergillus flavus, A. glaucas, A. niger, A. clavatonanica, A. flaviceps, Aspergillus spp., Penicillium spp., Epicoccum sp., Chaetomium spp., Alternaria tenuis, Fusarium spp., Cladosporium spp., Curvularia spp., Rhizopus sp., Dorotomyces, etc.

The summary of annual cost of pesticides and pest control equipment for Ministry of Food storage system is as follows:

CSD capacity = 450,000 tons
  = $ 450,000 (@ $ 1.00/ton)
LSD/TPC capacity = 1,100,000 tons
  = $ 550,000 (@ $ 0.50/ton)
Silo capacity = 225,000 tons
  = $ 56,250 (@ $ 0.25/ton)
  = $ 1,056,250

Traditional farm storage strucutres

The traditional farm storage practices and storage containers use in Bangladesh are:

i) Earthen vessel

ii) Mud bins

iii) Kerosine tin

iv) Gunny bags

v) Bamboo bins (Dole)

vi) Pura

vii) Gola

vill) Pucca Godown

Loss estimation

The Department of Food assumes that the approximate rate of losses occuring annually is about 58% WFP assumes that lossed in rice will be constant throughout the year at roughly 0.8% month with losses in wheat at the 0.6-0.8% range/ month for the period July-Feb and 1.3-2.0% month for the months of marchJune. Losses occur due to pest damage, transport loss, handling loss and losses due to long term storage.

Present approach

The Bangladesh Agricultural Research Institute (BARI) sucessfully completed a 3-year "Legume Postharvest Technology" Project financed by IDRC and which was started in July, 1981. An important feature of the project was that a number of disciplines such as Entomology, Plant Pathology, Agronomy, Agricultural Economics and Agricultural Engineering were involved to implement the various post-harvest studies. During this period, detailed studies on the incidence of insect pest, storage fungi, seed viability, evaluation of traditional storage containers, newly fabricated mechanical drier, marketing costs and margins of different pulses were carried out. After termination of this project, BARI included some important crops for post-harvest studies. The crops are groundnut, maize, kaon, wheat and onion.

Facilities regarding training programmes and extension activities till now have not been initiated but it is considered an urgent need.

Ministry of Food

Bangladesh agricultural research institute

All Director General's are directly related with the Secretary, Ministry of Food.

Constraints to current loss reduction practices

The following have been identified: (1) Lack of appropriate farm level post harvest machinery such as threshers (2) Lack of farm level storage facilities for groundnuts and grain legumes (3) Deficiency of trained manpower in Post-harvest technology. Country wide post-harvest loss reduction assessment was done only in paddy.

Needs in terms of project development


i) Two short term training/year (not exceeding 3 months)

ii) One M.S. degree

iii) One Ph.D. degree

National level Co-ordination: Organization/ Institutes those involved in post-harvest technology work have no notional level co-ordination.

Resource availability


BARI-Technologists 3, Agricultural Engineer-6, Pathologists-5, Entomologists-5 Bangladesh Rice Research Institute-12, Institute of Nutrition Food Science-17, Bangladesh Sugarcane Res. Institute-2, Institute of Food radiation Biology-14, Bangladesh Agri. University-19, Institute of Food Science & Technology, BCSIR-48


Storage facilities, capacity and design already mentioned;

facilities: well furnished laboratory

Financial needs: Not adequate but needs Tk. 1.00 million/year

Training Facilities: Not available both in Department of food and research Organizations.

Involvement of private sector in activity under review There is at present no involvement of the private sector in storage of Government handled food grain but 85% of grain is being handled by the private sector under traditional systems.


Integrated pest management strategies in grain storage systems in Myanmar

(Union of Burma)



This paper is a brief description of the grain industry of Burma, with a particular statement of the storage and pest control activies practiced in Burma.

Steps taken up for the improvement of storage and pest control activies are entirely those taken up by the Myanma Agricultural Produce Trading (MAPT) (formerly known as the Agricultural and Farm Produce Trade corporation.)

Integrated Pest Management Strategies in Grain Storage Systems, is entirely a new subject for the grain industry of Burma. It is learnt that the Agricultural sector of this country has introduced this system a few years ago. Therefore, it is expected that useful knowledge could be gathered from this training workshop and the Integrated Pest Management System can be introduced into the grain storage practices of this countly and the benefits of it can be enjoyed.


Burma, having a land area of 676,577 (261,228 sq.miles) lies between Latitudes 10N and 2831'N. Longitudes 92E. and 101E. It lies east of India and Bangladesh, south-west of China and west of Thailand and Laos. It is largest country in mainland South-East Asia.


Burma is a tropical country, the climatic conditions of it is favourable to grow various crops.

The climate of Burma comprises of a wet season (rainy season) from mid-May to mid-October and dry season from mid-February to mid-May. In the rainy season, most parts of the country get adequate rain to grow various crops.

The land under cultivation in Burma occupies about 20 million acres (8.0 million hectares) which is about 11.6% of the total area of the country. 9.39 million or 63.5% of the countrys' total active labour force of 14.79 million was employed in the production of agricultural crops in 1984-85. Hence, due to these favourable geographical and climatic conditions, the economy of Burma depends on the agricultural sector.


Fomerly known as the Agricultural and Farm Produce Trade Corporation (AFPTC), the Myanma Agricultural Produce Trading was the only organization authorised for the procurement, transporation, storage, milling and export of agricultural products and other government controlled items such as maize, beans and pulses.

About 15,414 permanent and 16,642 temporary staff is employed by AFPTC. It procures 4 to 4.5 million tons of paddy, about 70,000 tons of pulses about 20,000 tons of maize and about 4,000 tons of oil cakes through 1031 paddy buying depots and 172 buying depots for other crops. AFPTC owns 53 rice mills, the total capacity of which is 3742 tons per 24 hours. In addition, it also hires 21 co-operative rice mills and 962 private mills having capacitives of 664 tons per 24 hours and 27972 tons per 24 hours respectively. The Corporation processes about 2.5 million tons of rice from the paddy purchased.

A provincial and national review of current practices and problems related to Pest Control Activities in Burma.

The Myanma Agricultural Produce Trading is one of the (11) organisations formed under the Ministry of Trade. It is infect the largest organnisation under the Ministry, covering a very large field of business. Technical deparments such as the Rice Mill Engineering Department, the Rice Bran Oil Milling Department and the Pest Control Department are included in the organisational set-up of this organisation. The formation of the Postharvest Technology Application Centre (PTAC) is the latest addition to the set-up of this organisation. PTAC is purely a research department under taking the research and development activities in the field of rice milling, rice bran oil extraction, quality control, storage and pest control of agricultural products.

The Pest Control Department.

The MAPT is the only organisation which has the Pest Control Department in its' organisational set-up. This department was founded more than 40 years ago, and it has since taken the responsibility of prevention and control of pest infections required for the agricultural products handled by MAPT. In 1977, the department undertook the fumigation of stocks onboard vessels according to the contract terms laid down between the buyers and the seller. Furthermore, also in 1977, the department rendered pest control services for government departments, co-operatives and foreign missions, for which the department earned a regular income for MAPT. Within the period from 1977 to 1988, the department has carried out fumigation of 4,720,468 metric tons of rice and broken rice onboard 646 vessels, and within the same period, the department has earned a sum of K14,577,059/($718,533.59) through the execution of pest control services.

The Pest Control Department is headed by a team of managers who have gained an experience of more 20 years in the field of pest control. These managers were trained at distinguished institions in countries which have a high reputation in Pest Control Technology. The trainings and the countries attended by these Managers is given in Annexure (I).

There are 32 Pest Control Teams formed under the Pest Control Department and Stationed at various parts of the country. These teams tour round the buying departments, storage warehouses and rice mills and carry out pest control operations according to programme, Thus, pest control operations are carried out at the time grains were purchased, at time of storage and at time of export.

The capacity of the Pest Control Department can be estimated from the performances it has been undertaking.

The method of pest control adopted by the Pest Control Department is the chemical control method. All the chemicals used are imported items. Only a few of the equipments used are manufactured locally. Procedures followed in carrying out pest control operations were first tested in the laboratory and then under commercial scale and dosage rates were established so as to be most effective under the prevailing conditions of the country.

Types of pest control are divided into two as follows:

(a) prophylactic or the preventive and

(b) curative type

The preventive types of pest control include the disinfestation of warehouses and dusting of open piles of paddy and stacks of bagged grain. The curative measures include the space treatment and the fumigation method.

As Bruma is a tropical country, the battle against stored product insects is an everlasting campaign. As insect infestation can be present both in the field and at time of storage, losses occur at both these points. But, as this report is a view of the postharvest activities, only the losses that occur after harvest will be discussed.

It is learnt that substantial losses occur at the various stages such as at buying depots, on transportation and at time of storage. The losses that occur at the storage level consist of both quantity and quality losses. Quantity losses are caused by birds and rodents, insects, moisture, and spillages. quality losses are caused by insects, moulds and fungis and suncracking.


Heavy losses both quantitative and qualitative in the storage sector. This is a serious threat and the authorities are taking up steps for the improvement in the following areas of paddy and rice storage.

In the implementation of the above, local training programmes such as rice milling, storage management and pest control were organised.

Maintenence of the existing godowns and rehabilitation of storages capacities in the rice producing areas were carried out.

The Postharvest Technology Application Centre is now effectively carrying out less reduction and upgrading of quality actively both within its' capacity and with the aid of the various organisations. The following research projects and pilot studies related to bulk handling and storage of paddy have been undertaken by PTAC since 1986. (Table 1)

Technical cooperation with various organisations for research and development on Pest Harvest Technology of Foodgrains has been also implemented. (Table 2)

A team of technicians, comprising of a pest control technologist and a chemist, visited Burma, and made a short term field survey of the activities of the PTAC and the Pest Control Department. Monito ring of insecticide residues and the determination of dosage rate of funigants were carried out by this team is cooperation with PTAC and the Pest Control Depertment.

The MAPT therefore possess a competent group of technicians such as laboratory technologists, pest control technicians, and entonologists who are trained overseas and who have a long experience in the respective fields. But, technology is a subject, which is advancing with the passing of time. Therefore, it is expected that these technical workers have a good access to the fastest developments in technology by having a chance to attend the various training seminars and workshops held in the respective fields.

Pest control activities cannot be carried out efficiently due to the lack of good storage practice. Sometimes grading of beans and pulses is done in the same warehouse where fumigated stacks are stored. Also, separation of insect fragments dusts and impurities is carried out using a mechanical blower. This causes insects to spread to all places within the warehouse.

Interest and dicipline of the storage personnel play a vital roll in the storage and pest control systems. Sometimes, fresh arrivals are stacked on top of those which have been fumigated. Also, sometimes, high grade grains are stored very near to these stocks which are very heavily infested, such as bran, broken rice.

Old stocks Iying in the warehouses for a long period are also major constraints in rendering insect free condition for commodities that are meant for export. When fumigation is done only to these stacks which are selected for export; these old stocks become the main source of reinfestation.

A temperature of about 21 C and 75% R.H. is not uncommon is most of the grain producting areas. Therefore, the fight against the storage insects is naturally more severe than in these countries which have a temperate of cool climate.


Very recently, there was a change in the economic policy of the country. Most of the controlled items were released, and the private sector is allowed to participate in the purchase, transportation and sales of these items. This open door policy is bringing in private organisation into the new trading system. The assets belonging to the government departments will be available to the private sector either on loan or joint venture basis. Thus, there were be an expansion in the volume of business transaction in the country. This will mean an increase in the demand for pest control services for items handled by the private sector. Up to some extent of time, the requirement, both for domestic and export pest control services the government will be the only organisation that will have to undertake the job.

The other factor that hinders the effectiveness of pest control activities is the climatic factor of the country. As Bruma lies in the tropics, is an ideal condition for the breeding and spreading of storage insects.

Table 1

Sr. Research Titles Organization Years.
1. The effect of moisture content level and matting cover on the quality of paddy stored in heaps on the ground. ODNRI 1986/87
2. The study on the effect of dusting on stored paddy with different insecticides. ODNRI 1986/87
3. Survey of anthroped pest in food commodities stored in DHS godowns, Rangoon. ODNRI 1986/87
4. Replicated storage trials on paddy Impurities. ODNRI 1988
5. Preliminary study on the performance of mechanised warehouses of bulk storage of paddy. ODNRl 1988
6. The use of mobile flexible plastic silos. FAO 1988
7. A preliminary trial on quality of modified traditional field practice. ODNRI 1988

Table 2

Resources Research Areas Duration Remarks.
ODNRI Pest Control, storage 4 years United Kingdom.
FAO Temporary storage 1 years United Nations.
JICA Quality control 6 months Japan.

ODNRI Overseas Development National Resources Institute
FAO Food and Agriculture Organization
JICA Japanese International Cooperation Agency


  BURMA U.K. 1986 I.D.A.
  BURMA U.K. 1986 I.D.A.


Management of grain storage in the republic of Korea

1. The Status of Grain Storage

The grain loss in post harvest occurs mainly during the storage period. Many experts assume a 35% loss storage on the farm. Annual rice production amounts to six million metric tons. About 13-18% of production is handled by the government and merchants, while the rest remains at the farm and stored in warehouses.

During storage, a lot of grain is lost due to inadequate drying of grain and poor storage facilities by rats, birds, insect pests, and microorganisms.

The farm warehouse for grain.

(1) The present status of farm storage:

Generally, the method of grain storage is of two types: sack method using a storage bag etc. and storage method of grain in bulk. The type and place of farm storage is variable in Korea, but government grain is stored in bags. (See Table 1,2)

The warehouses for government procured and stored grain

(1) The present status of storage for government:

In 1982, there were 4,642 warehouses with a total floor space of 1,669,612 m. There was a storage capacity of about 4 million metric ton in 1986; provided by 7,578 warehouse with a total floor space of about 6 million m. In addition to the increase in grain storage facilities, there have been significant changes in the quality of such facilities. When the storage capacity and different grades of warehouse in 1982 is compared with those of 1986, has shown a positive improvement in quality. Increase in capacity of special grade and a decrease in third grade and subgrade facilities, has occurred.

Table 1. Changes of grade in grain warehouse

  Year Special Grade Grade 1 Grade 2 Grade 3 Sub Grade
Number 1982   25 327 950 3,340
  1986 136 6,235 1,207    
Floor space (m) 1982   74,711 167,743 260,762 566,396
  1986 188,100 2,237,400 369,600    
Storage capacity M/T 1982   143,200 202,977    
  1986 290,100 3,268,000 428,000 176,080 514,002

Table 2. Farm Storage Methods in Korea

Storage in Bulk Storage using bag
(1) Flat bulk storage (1) Warehouse having flat roof
(2) Bulk storage of a small cylinder type (2) Flat bulk storage
(3) A rice chest making of bamboo (3) Wooden floor
(4) A wooden rice chest (4) Room
(5) Steel silo  

Table 3. Location of Farm Storage

2. Administration system of government storage: 1guide system for the storage administrator

The Ministry of Agriculture and Fisheries appoints the following storage administration officers for the warehouses in their districts.

These personel will be in charge of admimstaring this guide and other instruments for the specific warehouse concerned.

2- Ouality inspection of government stored grain

Supervision of national agricultural products is done by the Inspection office National Agricultural Products Inspection Office (NAPIO)

For Inspection The grain is stored in accordance with a contract with government and the subsequert a contract with government and the regulations concerning warehouse management.

Items to be inspected

Inspection period:

The method of quality inspection: The quality of grain shall be checked by using the method of sample test. Samples shall be taken by type of grain, location, and stacks in the warehouse. If there is some possibility or indication of discoloration, degeneration, rotting and insect damage, all grain shall be tested.

Classification Period Hulled grain Unhulled grain
Safe period Nov. - Apr. Once a month Once a month
None-Safe period May - Oct. Twice a month Once a month
Danger period June - Sept. Twice each Once a month

Note: All warehouses should be checked regardless of the period when unusual weather condition such as storm and unusual high temperature occurs.

C. Control of insect and microrganisms during the storage period.

Grain is alive; it always breathes and consumes nutrients. The quality and quantity of gran have been reduced by the proliferation of microorganisms. Besises this, the quality of grain is influenced by moisture, temperature, and storage condition. Under the same warehouse, the metabolism of the grain increases rapidly with higher temperatures.

The rate of respiration is reduced by approximatey half for every 10C reduction. Insect pests reguire moisture the level of which is dependent on the species concerned, and ambiert conditions Populations are generally restricted below 12C moisture content, but multiply rapidly asove 14%. Insects are latent below 5C, active over 15C.

If microorganisms are present in the grain during storage, discoloration, biochemical change and decrease of germination rates occur. Microorganisms such as some moulds produce mycotoxin. For microbial growth in rice, temperatures af 30C and moisture contents of 16% are required.

The growth of microorganisms is restricted below 15C but increases rapidly over 25C.

(1) Insect in stored grain.

High temperature and humidity occur from July to September in Korea. A lot of insects and microorganisms are found at this time. There are approximately 19 species of insect. Sitophilus Oryzae (L), Oryzaephilus surinamensis (L), Tribolium confusum (J. du V.) Cryptoletes ferrugineus (Steph), Callosobruchus chinensis (L), are some of the most conernonly occurring species of stired products insects infesting rice beans and legmes. The following list of insect identifications refers to table 4.

  1. Sitophilus oryze (L)
  2. Sitophilus sasakii (Takahashi)
  3. Callosobruchus chinensis (L)
  4. Rhyzopertha dominiica (Fab.)
  5. Tenebroides mauritanicus (L.)
  6. Oryzaephilus surinamenis (L)
  7. Cryptoletes ferrugineus (Steph)
  8. Trogoderma granarium (Ev.)
  9. Attagenus megatoma (Fab.)
  10. Tribolium confusum (J.du.v)
  11. non-identification
  12. Alphitobius diaperinus (Span.)
  13. Alphitophagus bifasciatus (Say)
  14. Tenebrio obscurus (Fala)
  15. Sitotroga cerralella (Olive)
  16. Plodia interpunctella (Hubn)
  17. Pvralis farinalis (Zell)
  18. Carpophilus hemipterus (L)
  19. Acarus siro (L)
  20. Nemapogon granella (L)

(2) Microorganism occurrence in Korea

Sixty samples of deteriorated rice which were collected all over Korea were classified according to their color. The causitive microorganisms were then isolated and identified.

(A) 62 samples of deteriorated rice were classified according to color into 7 types: reddish yellow, light reddish yellow, light gray yellow, lightish light gray, dark gray and rice weevil type.

(B) The isolated microorganisms form 62 specimens of deteriorated rice were 44 species, 5 genera of molds, 1 species of yeast, and 14 species, and 4 genera of bacteria.

(C) The frequently observed microorganisms which caused the deterioration were A. glaucus group,A. oryzae, A. candidus and A. versicolor. Among bacteria, Bacillus was dominant.

These insects are very prolific. Tribolium confusum (J. du V.) and Sitophilus oryzae (L) etc. can survive despite low temperature, dryness and coldness from Decenber to January.

Table 4. The status of insect occurrence

Isolated Microorganism from Reteriorated Rice and their Frequencies

1) Moulds:      
1) Moulds: 156 P. commune 6
A. repens 154 A. carneus 3
A. candidus 125 A. niger 3
A. royzae 105 P. cased 3
A. chevalier) 96 P. miczynskji 3
A. fumigatus 83 Scop. brevicaulis 3
A. fumigatus 58 A. raperi 2
P. iolandicum 58 P. janthinellum 2
P. simplicissimum 30 P. purpurongenum 2
A. montevidensis 24 P. frequentans 2
A. wentii 23 P. waksmani 2
A. clavatus 18 P. funiculosum 2
P. jensej 16 P. duclauxi 2
Phizopus nigricans 16 Tricholerma lignorum 2
A. flavus 16 A. nutans 1
P. solitum 15 ASP. ochroceus 1
P. citrinin 13 A. roqueforti 1
Rhizopus arrihizus 9 P. resticulosum 1
A. penicilloieds 8 P. stekii 1
P. Ianosum 7 P. Ianoso-coerulum 1
P. viridicatum 7 unknown 12
A. nidulans 7    
2) Yeast:      
Trichosporon berendii 1    
3) Bacteria:      
B. cereus 103 Brev. tegumenticolon 6
B. coagulans 69 Stap. epidermis 5
B. subtilis 59 B. circulars 3
B. Iicheniformis 53 B. Ientus 2
Pseudomonas caviae 40 B. firmus 1
B. pumilus 37 Brev acetylicum 1
B. megoterium 16 Brev incerlium 1

A. = Aspergillus
P. = Penicillium
Scop. = Scopulariopsis
B. = Bacillus
Stap = Staphylocoocus
Brev = Brevibacterium

Control of insects and microorganisms

The moisture content of grain is decreased to 15% in order to continue to store grain for a long time. When government buys paddy rice, moisture limit must be below 15%.

Temperature and moisture content of stored grain are provented from increasing by ventilating the warehouse because of so much rain and high temperature in the summer season. Managers must observe relative humidity, grain temperature.

(c) Dosage and Exposure time by Aluminium phosphide (PH3)

Dosage and exposure time

Contents - Previous - Next