Disease Control


SASRI conducts research and provides services to minimise the effects of diseases on crop production. While many diseases affect sugarcane, five are common and are regarded as particularly serious, having a major economic impact on the crop. These are ratoon stunt (RSD), smut, mosaic, and brown and tawny rust.

All our advice and information on disease control can be found in the various publications, videos and services described below.

Sharon McFarlane

Senior Plant Pathologist


Senior Plant Pathologist

Tel: 031 508 7400 (Switchboard)
Tel: 031 508 7523 (Direct)
Email: sharon.mcfarlane@sugar.org.za

Role & Overall Purpose
  • To investigate outbreaks of disease in the field and to provide advice and support to Extension specialists and Local Pest, Disease and Variety Control Committees (LPD&VCC) relating to the identification, monitoring and management of sugarcane diseases.
  • To conceive, initiate, conduct and direct research in applied sugarcane pathology in order to provide a sound basis for the understanding of the epidemiologies of pathogens and for the management of diseases.
  • Extension pathology.
  • Communicating research findings and observations to growers, LPD&VCC’s and other interested parties.
  • Molecular identification of Fusarium species in sugarcane.
Research Interests
  • Diagnosis, epidemiology and management of diseases.
  • Effect of Fusarium species isolated from sugarcane on the development and fecundity of the borer Eldana Saccharina.
Key Outcomes
  • The development of mosaic and smut management strategies for the Mpumalanga region, Identification of fungicides for smut and brown rust management.
  • Certain Fusarium species isolated from sugarcane are attractive, promote the development and improve the fecundity of Eldana saccharina while other species are avoided by larvae and have a detrimental effect on larval development in vitro.
Key Publications

McFarlane, SA, Meyer, JH, Cadet, P and Rutherford, RS (2008). Investigation into the effect of nutrition on brown rust development in sugarcane. Proc S Afr Sug Technol Ass (in press).

van Antwerpen, T, McFarlane, SA, Buchanan, GF, Shepherd, DN, Martin, DP, Rybicki, ER and Varsani, A (2007). First report of maize streak virus infection of sugarcane in South Africa. Plant Disease (in press).

McFarlane, SA and Rutherford, RS (2005). Fusarium species isolated from sugarcane in KwaZulu-Natal and their effect on Eldana saccharina (Lepidoptera: Pyralidae) development in vitro. Proc S Afr Sug Technol Ass 79: 120-124.

  • BSc Honours (Natal).
  • MSc (Natal).

Information Sheets

9.1 Ratoon Stunt (RSD)

Ratoon stunt, formerly known as ratoon stunting disease (RSD) can cause substantial yield loss. This important bacterial disease occurs throughout the sugarcane industry although infection levels differ widely from region to region. Being a legislated disease, RSD must be managed according to the rules prescribed by the Local Pest, Disease and Variety Committee. The disease often goes unnoticed because there are no easily recognisable symptoms. The disease can only be reliably identified by submitting samples to a recognised RSD diagnostic laboratory for testing.

View Information Sheet

9.2 Smut

Sugarcane smut occurs throughout the South African sugar industry but is most common and severe in the northern irrigated areas and Zululand. Being a legislated disease, smut must be reported to the Local Pest, Disease and Variety Control Committee and must be managed according to the rules prescribed by the Committee.

View Information Sheet

9.3 Mosaic

Mosaic is most common in the cooler, southern and high-altitude inland areas of KwaZulu-Natal, but serious outbreaks can occur periodically in all parts of the industry. Being a legislated disease, mosaic must be reported to the Local Pest, Disease and Variety Control Committee and must be managed according to the rules prescribed by the Committee.

View Information Sheet

9.4 Sugarcane rust

Two types of rust currently infect sugarcane in South Africa. Brown rust has been in the industry for many years while tawny rust is a relatively new disease of sugarcane that currently only occurs in southern Africa. Orange rust occurs in most sugarcane industries around the world but has not yet been reported in South Africa. All three forms of rust can cause serious yield loss when severe. Registered fungicides are available for the management of brown and tawny rust in southern Africa and form part of SASRI’s orange rust incursion plan.

View Information Sheet

9.5 Sour Rot

Sour rot, caused by Phaeocytostroma sacchari, is a common fungus and usually a weak pathogen. It can, however, cause substantial reductions in purity when mature cane (usually 15 months and older) is stressed. It is most common in the high-altitude inland areas of KwaZulu-Natal where cane is grown on a longer cutting cycle. The disease does, however, occur periodically in other parts of the industry, particularly when cane is stressed, over-mature or lodged.

View Information Sheet

9.7 Pineapple Sett Rot

Pineapple sett rot is caused by a soil inhabiting fungus. Poor germination may occur when seedcane becomes infected after planting under unfavourable conditions or after hot water treatment.

View Information Sheet

9.8 Pokkah Boeng

Pokkah boeng (a Javanese term for twisted top) is a common and generally mild disease, the symptoms of which can be seen on most South African varieties. Susceptible varieties can, however, be severely affected. It is caused by a complex of common Fusarium species.

View Information Sheet

9.12 Roguing

The removal of diseased plants from the field (roguing) is an important measure for the management of smut in commercial fields. Roguing is also an essential, routine practise for the removal of stools infected with systemic diseases such as smut and mosaic, as well as off-types from seedcane nurseries.

View Information Sheet


Sugarcane diseases in Southern Africa

Disease control in sugarcane and the maintenance of optimum productivity depends on planting resistant or tolerant varieties; planting good quality, disease-free seedcane; eliminating volunteers before replanting; inspecting and roguing cane fields regularly; eradicating severely infected fields; and managing the crop well. The various diseases occurring in sugarcane in southern Africa are described, together with recommendations for their control.

View Book

Pest and Disease Guide

This is a handy pocket guide for easy identification of pests and diseases occurring in the South African sugar industry. The guide comes complete with pictures, descriptions of symptoms and brief related notes, and is available in both English and IsiZulu.

English | isiZulu

View Books

Seedcane Production

Planting good quality seedcane is a crucial step in profitable sugarcane production, reducing the incidence of serious systemic diseases such as ratoon stunt (RSD), smut and mosaic in commercial fields. By March 2023, only Certified and Approved Seedcane may be used to plant commercial fields in South Africa.

This manual outlines the importance of good quality seedcane and the procedures that need to be followed to produce Certified and Approved Seedcane.

View Book


To view any of the items below, please see the Illustrative Guides section of our eLibrary.

Sugarcane Diseases

English | isiZulu

Rust Identification
English | Afrikaans

Rust Biosecurity Alert
English  |  Afrikaans

Sugarcane Diseases

English | isiZulu

Rust Identification
English | Afrikaans

Rust Biosecurity Alert
English  |  Afrikaans


Ratoon Stunt Diagnosis

Ratoon Stunt (RSD), a major sugarcane disease which causes substantial yield loss, can only be reliably diagnosed in a properly equipped laboratory. SASRI offers a diagnostic service to farmers and also provides advice on the management of the disease.

Extension and Biosecurity Service

Together with Local Pest, Disease and Variety Control Committees, SASRI acts to monitor diseases and implement procedures to mitigate damage and loss. They also ensure that only gazetted varieties are planted in each control area.

Special Advisory Requests

Service to investigate new products on behalf of commercial companies to facilitate registration. Investigations can include testing of herbicides, fungicides, ripeners, fertilisers and pesticides.


Research in Disease Control investigates the biology and ecology of the primary pathogens of the industry and their impact on crop yield, with a view to developing management strategies. Visit CROP PROTECTION for more info.

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