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Facilitating regional trade of agricultural commodities in Eastern, Central and Southern Africa

Table of Contents

Phytosanitary Standards to restrict the further rapid spread of the Larger drain Borer (LGB) in the region.

Collected and Edited by R. Lindsay SEMPLE and Geoffrey I. KIRENGA

Prostephanus truncatus

Adult beetle larva (ICI copyright)


The designations employed and the presentation of the materials in this document does not imply the expression of any opinion whatsoever on the part of the FAO, EEC, NRI, IMO, PTA, SADC, OAU, IAPSC and CTA concerning the legal status of any country, territory, city or area or of its authorities, or concerning the delimitation of its frontiers or boundaries. Neither does it infer endosement or support for any technical product, systems or manufacturer.

ISBN 9987 24 002-X


Phytosanitary Standards to restrict the further rapid spread of the Larger Grain Borer (LGB) in the region.

Guidelines prepared under the FAO/EEC Cooperative Programme

Contributing authors (either under contract, or from previously printed material):


NRI Pesticides/LGB control generally

Robert W.D. TAYLOR

NRI Use of fumigants including on-hoard ships


NRI Use of fumigants (under sheet applications)


NRI Inspection, sampling, grain quality


FAO AGPP Phytosanitary Principles, IPPC


NRI Port phytosanitary operations

Melanie J. DALES

NRI Use of pesticides to control LGB


(TCP/URT/9161) Phytosanitary Legislation

Patrick S. DALE

(TCP/URT/9161) Phytosanitary Regulations


TCP/RAF/2734(A) Operations issues Plaat Quarantine


IGROX LTD (UK) Fumigation technology on board ships

Collated and edited by:

R. Lindsay SEMPLE

Editor in Chief. Regional Coordinator GCPP/RAF/300/EEC

Geoffrey I. KIRENGA

National Expert, GCPP/RAF/300/EEC


Permission to make digital or hard copies of part or all of this work for personal or classroom use is hereby granted without fee and without a formal request provided that copies are not made or distributed for profit or commercial advantage and that copies bear this notice and full citation on the first page. Copyright for components of this work owned by others than FAO must be honoured. To copy otherwise, to republish, to post on servers, or to redistribute to lists, requires prior specific permission and/or fee.

Request permission to publish from:

The Chief Editor,
FAO, Viale delle Terme di Caracalla,
00100 Rome, Italy,

This electronic document has been scanned using optical character recognition (OCR) software and careful manual recorrection. Even if the quality of digitalisation is high, the FAO declines all responsibility for any discrepancies that may exist between the present document and its original printed version.

Table of Contents


List of acronyms


Referees from the region

Chapter 1 - Quarantine principles

1.1 Introduction

1.2 Approaching quarantine standards

1.3 Specification design

1.3.1 Contingency planning
1.3.2 Compliance inspection
1.3.3 Pest tolerance categories and maximum pest limits (MPL's)

Chapter 2 - Phytosanitary legislation and regulations

2.0 Phytosanitary legislation

2.1 Plant protection legislation

2.1.1. General principles for preparing legislation
2.1.2 Structure of legislation texts

2.2 Plant quarantine regulations

2.2.1. The responsibilities of phytosanitary services
2.2.2. Safeguards against LGB

Chapter 3 - Quarantine treatment of maize consignments for the exclusion and control of the larger grain borer (LGB), utilizing grain fumigation and grain protectants

3.1 Considerations for management

3.1.1. Is fumigation appropriate?
3.1.2. The need for fumigation and timing of treatments
3.1.3. Action before fumigation
3.1.4. Integrated commodity management
3.1.5. General safety considerations in fumigation

3.2. Code of practice for the fumigation of bagged maize, in stacks, under gas-proof sheets, to control the larger grain borer

3.2.1. Introduction
3.2.2. Checking the effectiveness of treatments
3.2.3. Safety considerations
3.2.4. Requisites for effective fumigation
3.2.5. Fumigation using phosphine
3.2.6. Fumigation with methyl bromide
3.2.7. Application equipment
3.2.8. Construction of stacks for fumigation
3.2.9. The measurement of gas concentrations to determine efficacy of fumigation
3.2.10. Post-treatment action

3.3 Ship board fumigation

3.3.1. Fumigation at anchor or intransit (with crew on board) Suitability of vessels Testing for leakage Key safety requirements in ship board fumigation (see IMO guidelines)

3.3.2. Ship fumigation while ship is evacuated by personnel and crew
3.3.3. Ship board fumigation using phosphine
3.3.4. Application after loading bulk maize without prior installation of tubing
3.3.5. Fumigation of shipping containers
3.3.6. Ship inspection
3.3.7. Fumigation of enclosed metal truck and rail trailers

3.4 Use of residual pesticides as structural treatments and as grain protectants

3.4.1. Supplementary treatment on surfaces of bags, storage structures, and transport:
3.4.2. Admixture of maize with grain protectant insecticide
3.4.3. General safety in use of insecticides

Chapter 4 - Standardized methods for inspection and sampling of shelled maize consignments: certifying freedom from LGB or other quarantinable insect pests, and for quality analysis in trade

4.1 Sampling of maize (as grain)

4.1.1. Introduction
4.1.2. Definitions
4.1.3. Principles of representative sampling
4.1.4. Method for sampling from bags
4.1.5. Method for sampling from static bulk

Chapter 5 - LGB detection methods - use of pheromone traps

5.1. Introduction
5.2. Guidelines for the use of pheromone trapping for the larger grain borer

Technical data sheets 1 - 18

1. Why all the fuss about LGB?

1.8 Identifying LGB: family bostrichidae

2. LGB as a critical quarantine pest

Example of - The plant protection ordinance

3. The plant protection regulations

4. Plant quarantine

Inspection stations

5. Import/export controls

6. Principles of plant quarantine as related to international trade

7. Glossary of related phytosanitary terms

8. Management of imported comodities

Procedures for handling bags
Options for receiving bulk at a bag-handling port
Procedures for handling bulk
Low volume bulk

9. Developing standardized grades and quality standards for the regional trade of maize in eastern and southern Africa

9.1 Quality and grading of commodities
9.2. Maize grain grade specification

10. Fumigation rules

11. Term used in fumigation

12. Sheeting specifications and sealing of stacks

12.1 Sheeting specifications and sealing of stacks
12.2 Making stacks gas-tight

13. Calculation of Ct products

14. Recommendations on the safe use of pesticides in ships

1. Introduction
2. Prevention of infestation

2.1. Maintenance and sanitation
2.2. Main sites of infestation

3. Chemical control of insect infestation

3.1. Methods of chemical disinfestation
3.2. Disinfestation of empty cargo spaces
3.3. Disinfestation of food stores, galleys, crew and passenger accommodation
3.4. Disinfestation of cargoes and surrounds
3.5. Carriage of fumigated freight containers, barges and cargo transport units on a ship

4. Control of rodent pests

4.1. General
4.2. Fumigation and baiting
4.3 Rodent baits (chronic poisons permitted for use by ship's personnel)

5. Regulations for the use of pesticides

5.1. National and international controls on pesticides usage

6. Safety precautions - general

6.1. Pesticide materials
6.2. Space and surface spraying (See also 3.1.2 above)
6.3. Fumigation
6.4. Contact insecticides in the cargo space, admixture with raw grain
6.5. Exposure to pesticides resulting in illness

Appendix 1 - Pesticides suitable for shipboard use
Appendix 2 - Threshold limit values (TLV) for vapors in air

15. Forced application and gas distribution systems in bulk grain

15.1 Requirements
15.2 Alternative management options

16. The international grain trade

Types of export sale
Chartering grain shipments
WFP charter party, part II, states
Role of chartering broker
Port phytosanitary inspectors

17. Insecticide admixture at small-scale farmer level

18. Contract specifications with regard to LGB when arranging for a maize purchase from a country known or suspected to be infested by LGB

Further readings and references

Further readings including references for extracted material
Specific references on safety and use of pesticides including fumigants
Some specific references for shipboard fumigation

Useful contact addresses