Crop Protection

Key Areas

This programme develops integrated management strategies that minimise the effects of pests and diseases on crop production in a sustainable manner.

Research in this Key Area focuses on:

  • Development of proactive threat specific counter-measures and biosecurity incursions plans;
  • Generation of knowledge of the biology, pathogenicity and epidemiology of pathogens posing potential incursion threats to the industry, as well as the agroecology, behaviour and reproductive biology of new potential pests; and
  • Development of improved procedures and diagnostic technologies to ensure that varieties released or propagated into the industry, or imported via the industry Quarantine Facility, are free of pathogens and pests. The information and knowledge gained in this Key Research Area are applied towards the development of Integrated Management tactics for potential new pathogen and pest incursions into the industry.

Research in this Key Area focuses on:

  • Investigation of the biology and ecology of the primary pathogens and pests of the industry with a view to the development of integrated management tactics and knowledge exchange with the grower community; and
  • Assessment of the impact on crop yield of the primary and emerging pathogens and pests in the industry to facilitate grower decision-making regarding the implementation of management tactics. The information and knowledge gained in this Key Performance Area are applied to the development of integrated management tactics for the major pathogens and pests in the industry.

Research in this Key Area seeks to develop knowledge regarding the biological basis of sugarcane resistance to pathogens and pests in order to develop approaches, resources and technologies to enhance resistance breeding in Commercial Breeding.

Research in this Key Area seeks to develop cost-effective technologies that permit the establishment of sugarcane agro-ecological environments in which pathogens and pests are suppressed to low levels by benign biological or ecological means.

Several complementary habitat management technologies are considered, including:

  • Push-pull technology
  • Biodiversity management, including wetland, riparian zone and vegetation corridor restoration;
  • Crop husbandry, including crop rotation, use of fallow crops, nutrient management and crop residue management;
  • The Sterile Insect Technique; and
  • Parasitoid and entomo-pathogen release.

Investigations in this Key Research Area focus on the development of a suite of effective pathogen and pest control agents that are agriculturally, environmentally, ecologically and economically sustainable.

Research focuses on a series of technologies, including:

  • Development of pheromones and traps to enable monitoring and rational agrochemical application programmes, primarily for eldana;
  • Search for more benign alternative chemistries; and
  • Development of superior application tactics and product formulations.
  • Download list of agricultural remedies registered for use in South Africa.

Dr Lawrence Malinga

Programme Manager: Crop Protection; Senior Research Entomologist

Current Projects

Variety Evaluation – Diseases
Additional chemistries and strategies for sugarcane pest and disease control
Sterile Insect Technique for eldana management: Field release trials
X-Ray Irradiation for Eldana SIT
Comparison of diversity and abundance of non-target organisms on Bt and non-Bt sugarcane.
Effect of genetically modified sugarcane in combination with sterile insect releases to control Eldana saccharina
Development of an IRAC laboratory-based Eldana saccharina resistance monitoring protocol
An investigation of insect trap designs and deployment using eldana attractants to monitor eldana infestation in Bt sugarcane
Agronomic assessment of the herbicide tolerance trait in Bt GM sugarcane
Prediction of quantitative resistance to sugarcane pests and diseases by means near infra-red spectroscopy
Spectroscopic determination of YSA-induced stress in sugarcane
A P&D risk model as a precursor to development of an early warning system (EWS)
Yellow sugarcane aphid and thrips varietal susceptibility
The effect of steel slag amendments on yellow sugarcane aphid infestations and cane yields.
An investigation of the population dynamics of yellow sugarcane aphid with a particular emphasis on movement patterns between plants
Biodiversity management and its place in sugarcane agriculture
The eldana microbiome
Use of boron for the control of Eldana saccharina and Fusarium in sugarcane
Determination of sugarcane yellow leaf virus elimination efficiency using molecular techniques
Protection of NovaCane® plantlets against smut and other fungal diseases
Understanding orange rust in the South African context

Dr Lawrence Malinga

Programme Manager: Crop Protection
Senior Research Entomologist

Tel: 031 508 7400 (Switchboard)
Tel: 031 508 7485 (Direct)
Email: lawrence.malinga@sugar.org.za

Role & Overall Purpose
To initiate and conduct research, technology development and knowledge exchange projects to ultimately enable the integrated pest management (IPM) of current and emerging pests of sugarcane by small- and large-scale growers.
Expertise
Biological Control, Entomology, Nematology, Organic Control, Technology Transfer, Project Management.
Research Focus
Eldana F1 Sterile Insect Technique: Assessment of X-ray irradiation as an alternative to gamma irradiation

Sterile Insect Technique F1 Eldana saccharina management: Cage and field release proof-of-concept studies

Comparison of diversity and abundance of non-target organisms on Bt and non-Bt sugarcane

Effect of genetically modified sugarcane in combination with sterile insect releases to control Eldana saccharina: a cage trial

Development of an IRAC laboratory-based Eldana saccharina resistance monitoring protocol

Technology Development for Small-scale Growers: Pest, Disease, Weed and Variety Management

Key Publications
Journal Publications
  • Karabo, B. and Malinga, L.N., 2025. Research Advancements on the Application of Sterile Insect Technique for the Control of Lepidopteran Pests Over the Past Two Decades: A Systematic Review. bioRxiv, 2025-01.DOI: 10.1101/2025.01.17.633492
  • Mawcha, K.T., Malinga, L., Muir, D., Ge, J. and Ndolo, D., 2024. Recent Advances in Biopesticide Research and Development with a Focus on Microbials. F1000Research, 13, 1071. DOI: 10.12688/f1000research.154392.5
  • Malinga L.N. and Laing, M.D. 2024. A Review of Pesticides for the Control of Some Cotton Pests. Annals of Agricultural & Crop Sciences, 9(1): 1148. DOI: 10.26420/annagriccropsci.2024.1148
  • Malinga L. 2024. A Novel Approach to the Sterile Insect Technique (SIT) for Eldana saccharina Management in South Africa. Sugar Tech, 26: 629–634. DOI: 10.1007/s12355-024-01378-0
  • Malinga L. and Laing, M.D. 2024. Lifecycle, Hosts and Importance of Some of the Major Cotton Insect Pests in South Africa: A Review. Asian Journal of Biological Sciences, 17(4): 624-639. DOI: 10.3923/ajbs.2024.624.639
  • Malinga, L. and Laing, M. 2023. Farmers' Production Practices, Incidence and Management of Pests and Diseases, Extension Services, and Factors Limiting Cotton Production and Quality in South Africa. South African Journal of Agricultural Extension, 51(3): 79–99. DOI: 10.17159/2413-3221/2023/v51n3a14462
  • Malinga L, Laing M. 2023. Cost Analysis of Biopesticides and Chemical Insecticides: Implications for Cotton Farmers in South Africa. Entomology and Applied Science Letters, 10(4): 44-55. DOI: 10.51847/YA2wqC4r3i
  • Malinga, L.N. and Laing, M. D., 2022. Role of Microbial Biopesticides as an Alternative to Insecticides in Integrated Pest Management of Cotton Pests. In: D. R. Eduardo (ed.), Insecticides - Impact and Benefits of Its Use for Humanity, IntechOpen, London. DOI: 10.5772/intechopen.100400.
  • Malinga, L.N. and Laing MD. 2022. Efficacy of Biopesticides in the Management of the Cotton Bollworm, Helicoverpa armigera (Noctuidae), under Field Conditions. Insects, 13 (8): 673. DOI: 10.3390/insects13080673
  • Malinga, L.N. and Laing, M.D., 2021. Efficacy of Three Biopesticides Against Cotton Pests under Field Conditions in South Africa. Crop Protection, 145: 105578. DOI: 10.1016/j.cropro.2021.105578
  • Malinga, L. 2021. The Importance and Economic Status of Cotton Production. Academia Letters, 2317: 1-8. DOI: 10.20935/AL2317
  • Malinga L. 2019. Southern and Eastern African Cotton Forum: Platform for the Advancement of Cotton Production in Africa. South African Journal of Science, 115 (9/10): 6-8. DOI: 10.17159/sajs.2019/6358
  • Malinga, L.N. 2017. Evaluation of Plant Extracts for the Control of Helicoverpa armigera, Diparopsis castanea, and Earias insulana in Cotton for Small-Scale Farmers. Cotton Research Journal, 8 (1): 12-19.
 
Popular Publications
  • Malinga, L. and Smith, R. 2025. What insects are there in my field? The Link, 34 (2).
  • Mofurutsi, T., Mchunu, L., Buthelezi, K., Jithoo S. and Malinga, L.2024. Sustainable sugarcane farming: Empowering small-scale growers. The Link, 33 (5).
  • Malinga L. 2024.Sterile insect technique application against sugarcane stalk borer Eldana saccharina. ISSCT Bulletin, 7. October 2024. https://issct.org/2024/10/22/issct-bulletin-october-2024/
  • Malinga L. 2024. Second Research Coordination Meeting of the Food And Agriculture Organization of The United Nations (FAO) and the International Atomic Energy Agency (IAEA) Coordinated Research Project - Vienna, Austria. Rostrum, 2024 (113), 13-15.
  • Malinga, L. and Rutherford, S., 2022. F1 – Fast-tracking the sterile insect technique for eldana control. The Link, 31 (1): 12-13.
  • Van der Westhuizen, M. and Malinga, L. 2021. Cotton: (Gossypium hirsitum L.) (American Upland cotton) Breeding desktop study – A short review. Cotton South Africa. chrome-extension://efaidnbmnnnibpcajpcglclefindmkaj/https://cottonsa.org.za/wp-content/uploads/2021/03/7.-Breeding-desk-top-study.pdf
  • Malinga L. 2019. Overview and outlook for South Africa's cotton sector. Cotton: Review of the world situation, 73 (2): 5-8.
  • Kranthi, K. R., Malinga, L. and Mubvekeri, W. 2018. Perspectives on cotton research and ideas for Africa- Proceedings & recommendations of the XIV Meeting of the Southern & Eastern Africa Cotton Forum (SEACF). The ICAC Recorder, 36 (3): 4-13.
 
Conference Proceedings
  • Smith, R.; Malinga, L.N.; Bouwer, G. 2025. Arthropod diversity and abundance under irrigated and rainfed conditions in South Africa sugarcane, in Proceedings of the 2nd International Electronic Conference on Entomology, 19–21 May 2025, MDPI: Basel, Switzerland.
  • Malinga, L. N. 2025. Application of sterile insect technique for the management of Eldana saccharina in South Africa: Two decades of research. Proceedings of the Third International Conference on Applications of Radiation Science and Technology (ICARST-2025), Vienna, Austria.
  • Malinga, L. N. 2025. Impact of sterile insect technique (SIT) against Eldana saccharina Walker (Lepidoptera: Pyralidae) in sugarcane. Proceedings of the Combined Congress, University of Limpopo, Polokwane, January 2025.
  • Mathonsi, S., Malinga, L. and Bambo, K. 2024. Selection of oviposition substrate by the sugarcane stalk borer Eldana saccharina Walker (Lepidoptera: Pyralidae) females for sterile insect technique. Proceedings of the ISSCT XIII Pathology and XI Entomology Joint Workshop, Salta, Argentina.
  • Lauchande, V., Malinga, L. and Munyai C. 2024. Effect of genetically modified sugarcane in combination with sterile insect releases to control Eldana saccharina: a shade house trial. UKZN Postgraduate Research & Innovation Symposium Proceedings.
  • Msele, K., Malinga, L. and Munyai C. 2024. Baseline susceptibility of laboratory-reared Eldana saccharina larvae to Bacillus thuringiensis Cry toxins and the Coragen insecticides. UKZN Postgraduate Research & Innovation Symposium Proceedings.
  • S Singh, L Malinga, C Weldon, D Conlong. 2024. Dose mapping of an X-ray irradiator with application to the sterile insect technique for the control of Eldana saccharina in sugarcane. Proceedings of The South African Sugar Technologists' Association, 96: 139.
  • S Singh, L Malinga, C Weldon, D Conlong. 2024. Effect of X-ray irradiation on the sterility of Eldana saccharina for the sterile insect technique in sugarcane. XXVII International Congress of Entomology Proceedings.
  • Johnson J, du Toit G, Asia H, Conlong D, Malinga L. 2024. Sterility and flight ability of Ceratitis capitata using X-ray irradiation as an alternative to gamma irradiation for the sterile insect technique. XXVII International Congress of Entomology Proceedings.
  • Beukes PR, Conlong D, Singh S, Malinga L, Munhenga G, Mulcahy M, Johnson J, Hlatshwayo N, Lieberman J. 2024. The importance of dosimetry in optimizing radiation doses received by insects for sterile insect technique. XXVII International Congress of Entomology Proceedings.
  • Malinga, L.N. 2023. A novel approach to the sterile insect technique (SIT) for the management of Eldana saccharina in South Africa. Proceedings of the International Society of Sugarcane Technologists, India, 31: 686–691.
  • Singh S., Malinga L., Weldon C. and Conlong D. 2023. Dose mapping of an X-ray irradiator with application to sterile insect technique (SIT) for the control of Eldana saccharina Walker (Lepidoptera: Pyralidae) in sugarcane. Proceedings of the 2023 ESSA Congress, July 2023.
  • Smith, R., Malinga, L. and Bouwer, G. 2023. Abundance and diversity of ground-dwelling arthropods under rain-fed and irrigated sugarcane in South Africa. Proceedings of the South African Sugar Technologists' Association, 95: 187.
  • Malinga, L. and Laing, M. 2023. Efficacy of microbial biopesticides on the control of cotton pests in South Africa. Proceedings of ICGEB 'Trends in Microbial Solutions for Sustainable Agriculture' Workshop in Belgrade, Republic of Serbia
  • Lauchande, V., Malinga, L. and Munyai C. 2023. Effect of genetically modified sugarcane in combination with sterile insect releases to control Eldana saccharina: a Cage Trial. UKZN Postgraduate Research & Innovation Symposium Proceedings.
  • Malinga, L.N. and Laing, M. 2023. Farmers' production practices, incidence and management of pests and diseases, extension services, and factors limiting cotton production and quality in South Africa. Proceedings of the 2nd International Electronic Conference on Agriculture, 1–15 November 2023, MDPI: Basel, Switzerland.
  • Malinga, L. 2016. Efficacy of organic nematicides on Meloidogyne javanica for small-scale cotton farmers in South Africa. Proceedings: World Cotton Research Conference – 6 and 2016 Biennial Conference of the ICGI, Goiânia, Brazil.
  • Malinga, L. 2015. Efficacy of biopesticides for pest control in cotton. Proceedings: 19th Congress of the Entomological Society of South Africa, Rhodes University: Grahamstown, South Africa.
  • Thompson G., and Malinga, L. 2014. The role of scientific research in making cotton a sustainable and profitable business in Africa. Proceedings: XII Meeting of the Southern and Eastern African Cotton Forum: Maputo, Mozambique
  • Malinga, L. 2011. Quantitative assessment of insect pests and predatory arthropods on intercropped organic cotton in South Africa. Proceedings: 17th Congress of the Entomological Society of South Africa, University of Free State: Bloemfontein, South Africa.
  • Malinga, L. 2010. South African cotton production and research report integrated pest management in cotton. Proceedings: 9th & 10th Meetings of the Southern and Eastern African Cotton Forum and the IPM Workshop, Lusaka, Zambia.
  • Malinga, L. and E. Eulitz. 2008. Organic insecticides and nematicides for small-scale cotton farmers. 23rd International Congress of Entomology, Durban, South Africa.
  • Malinga, L. 2007. Efficacy of natural substances for pest control in organic cotton by small-scale farmers. Proceedings: 16th Congress of the Entomological Society of South Africa, Stellenbosch University: Stellenbosch, South Africa.
  • Malinga, L. 2005. Constraints of cotton pest control in small-scale farming systems. Cotton Workshop, ARC-IIC: Rustenburg, South Africa.
  • Malinga, L. 2005. Cotton pests and their lifecycle. Cotton Extension Workshop, ARC-IIC: Rustenburg, South Africa.
Qualifications
  • BSc in Zoology and Entomology, University of Fort Hare
  • BSc (Hons) in Entomology, University of Fort Hare
  • MSc in Entomology, University of Fort Hare
  • PhD in Entomology, University of KwaZulu-Natal