September 2018

LISA ROTHMANN, Plant Sciences Department, University of the Free State and MIEKIE HUMAN, research assistant, Grain SA

Sclerotinia sclerotiorum is the causal agent of Sclerotinia stem rot on soybean and Sclerotinia head rot on sunflower. The fungus can infect more than 400 host species and can survive in the soil for up to eight years (depending on environmental conditions) – thus making this disease a challenge to manage.

No resistant soybean or sunflower cultivars are available and only a few chemical control products are registered for use against Sclerotinia.

In the light of the above challenges and after attending the National Sclerotinia Initiative in Minnesota in January last year, we created a platform for young researchers to assist one another and share their experiences with Sclerotinia research in South Africa. However, there was significant interest from beyond academic institutions, and so the South African Sclerotinia Research Network (SASRN) was born.

SASRN is a virtual community of practice for Sclerotinia researchers in South Africa and serves as a platform where collaborations can be established, and parallel and comprehensive research goals can be met that benefit multiple investigators and the public. We aim to generate social and academic capital where experienced investigators can exchange knowledge gained with peer investigators.

In September last year, SASRN had its inaugural meeting and has since then continued working with Grain SA as well as industry and academic partners. Currently, SASRN is applying for research funding to investigate solutions for Sclerotinia diseases of soybean and sunflowers and, in future, canola.

Prediction model
Researchers at the University of the Free State are developing a prediction model to assist producers in identifying the risk of Sclerotinia disease developing at critical growth stages during the cropping season.

Disease forecast models serve as an early warning system to assist producers in optimising the timing of fungicide applications to ensure optimal efficiency. In Europe, canola field experiments between 1981 and 2004 indicated that fungicide sprays were only 27% to 33% cost-effective against Sclerotinia stem rot (Koch et al., 2007).

In South Africa, chemical agents represent a significant portion of a producer’s production costs, and forecast models can assist producers in either minimising fungicide applications or increasing the efficacy of the application without compromising the degree of control.

Thus the objective is to accurately predict when the host, environment and pathogen interact in such a manner that disease can occur and can cause economic loss. The effects of other driving variables such as resistance, planting dates and cropping practices are also considered.

There are three key issues which SASRN would like to focus on:

  • Generate a local centre of excellence and expertise.
  • Be the ‘face’ for Sclerotinia researchers nationally and inform the international community of the role South Africa can play in Sclerotinia research.
  • Finding practical solutions for South African producers against diseases caused by Sclerotinia spp.

While producer-focused research to develop practical management strategies to Sclerotinia diseases is the main focus of the network, the collaborations established by the network is also a crucial aspect. The collaborations promote communication between parties involved, preventing duplication and allowing researchers to inform industry directly of findings, and vice versa.

This network is also a platform where industry and academia can listen to the needs of producers with a view of actively resolving issues through applied and directed research questions. The community of practice established will drive the communication between producers and network members.

If you are a researcher or producer and you are interested in connecting with us and growing our network, please contact Lisa at Please support our Facebook page, South African Sclerotinia Research Network, tag us @sclerotiniaza, use the #sclerotiniaZA or contact if you are interested in more information.

Publication: September 2018

Section: Focus on integrated pest control