In my position at CRI, I am responsible for coordinating research in the Preharvest disease programme, conducting research in the field of citrus fruit and foliar diseases, publication of research results in accredited journals and for ensuring technology transfer and reports of all research projects to the citrus industry in South Africa.
My team
Technical assistant: Lize Rostoll
Post-doctoral fellow: Angel Maduke
PhD student: Angelique de Wet (PhD)
MSc students: Marcelle Booysen (MSc); Lisa Botha(MSc Agric); Streicher Claassens (MSc Agric); Paul Els (MSc); Martin Errenrich (MSc Agric); Alecia Heyns (MSc Agric); Mmamoloko Makwena (BSc Agric); Leanne Meyer (MSc); Tisetso Nkuna (BSc Agric)
BSc Hons student: Leana Pauw (BSc Hons)
My Publications
Journal Articles (18)
Theron, E, van Niekerk, JM, van der Waals, J.E. (2026) In vitro phosphonate sensitivity of South African citrus Phytophthora nicotianae isolates. Acta Horticulturae. 1448. doi: 10.17660/ActaHortic.2026.1448.69
Alabi, GO, Maharaj, V, van der Waals, J.E., Invernizzi, L, Coutinho, TA (2026) Managing Brown Rot Disease of Citrus Fruit Using Plant Extracts. Journal of Phytopathology. 174. doi: 10.1111/jph.70254
Cruywagen, EM, Sutherland, R, Nkosi, BZ, van der Waals, J.E., Truter, M (2026) Multiple large and small-spored Alternaria species causing leaf spot of potato in South Africa.
Theron E, van Niekerk JM, van der Waals JE (2025) A review of the use of phosphonates in the management of Phytophthora nicotianae in citrus in South Africa. Phytoparasitica. 53. doi: 10.1007/s12600-024-01234-7
Strydom RF, Wilson CR, Tegg RS, Balendres MA, van der Waals JE (2024) Advancements in Spongospora subterranea: Current Knowledge, Management Strategies, and Research Gaps. Potato Research. 67. doi: 10.1007/s11540-024-09701-8
Coutinho TA, van der Waals JE (2024) Historical perspective on 120 years of agriculture: Highlights from research published in the SAJS. South African Journal of Science. 120. doi: 10.17159/sajs.2024/18965
Liakos C, Ibanez V, Lebre P, Derie ML, van der Waals JE, du Toit L, Dutta B, Kvitko B, Cowan D, Coutinho TA (2024) The Bacterial and Viral Communities Associated with OnionBacterial Bulb Rot. Phytobiomes Journal. doi: 10.1094/PBIOMES-11-23-0121-R
Gush SL, Lebre P, Coutinho TA, Cowan D, van der Waals JE (2024) Disentangling Shifts in the Soil Microbiome of Potatoes Infected with Rhizoctonia solani Anastomosis Group 3-PT in Search of Potential Biocontrol Agents. Phytobiomes Journal. 8. doi: 10.1094/pbiomes-06-23-0046-r
Theron E, Bophela K, Bisschoff J, Shin G, Coutinho TA, van der Waals JE (2022) Survey of Soft Rot Pectobacteriaceae Infecting Potatoes in South Africa. Potato Research. 66. doi: 10.1007/s11540-022-09598-1
van der Waals JE, Kruger K (2020) Emerging potato pathogens affecting food security in southern Africa: Recent research. South African Journal of Science. 116. doi: 10.17159/sajs.2020/8055
Simango K, Slabbert C, van der Waals JE (2020) Alternative hosts of Spongospora subterranea f. sp. subterranea in southern Africa. European Journal of Plant Pathology. In Press. doi: 10.1007/s10658-020-01993-z
Mushonga K, Steyn JM, Swart WJ, van der Waals JE (2020) Plant-soil feedback responses of four dryland crop species under greenhouse conditions. Plant-Environment Interactions. doi: 10.1002/pei3.10035
Moleboheng M, Modisane KJ, Apostolides Z, van der Waals JE (2020) Metabolomic Fingerprinting of Potato Cultivars Differing in Susceptibility to Spongospora subterranea f. sp. subterranea Root Infection. International Journal of Molecular Sciences. 21. doi: 10.3390/ijms21113788
Muzhinji N, van der Waals JE (2019) Population biology and genetic variation of Spongospora subterranea f. sp. subterranea, the cause of powdery scab and root galls on potato in South Africa.. Phytopathology. doi: 10.1094/PHYTO-12-18-0467-R
Gush, S, Muzhinji, M, Truter, M, Van der Waals, J. E. (2019) First Report of Rhizoctonia solani AG 2-2IIIB Causing Elephant Hide on Potato Tubers in South Africa. Plant Disease. 103. doi: 10.1094/pdis-10-18-1850-pdn
Mbedzi PP, Van den Hooven L, Vorster BJ , Van der Waals J (2019) Screening for Sclerotinia sclerotiorum resistance using detached leaf assays and simple sequence repeat markers in soybean cultivars. Crop Protection. 215. doi: 10.1016/j.cropro.2019.104909
Shutt VM, Shin G, van der Waals JE, Goszczynska T, Coutinho T (2018) Characterization of Ralstonia strains infecting tomato plants in South Africa. Crop Protection. 112. doi: 10.1016/j.cropro.2018.05.013
Amy Charkowski, Carlos Blanco, Guy Condemine, Dominique Expert, Thierry Franza, Christopher Hayes, Nicole Hugouvieux-Cotte-Pattat, Emilia L´ opez Solanilla, David Low, Lucy Moleleki, Minna Pirhonen, Andrew Pitman, Nicole Perna, Sylvie Reverchon, Pablo Rodr´ıguez Palenzuela, Michael San Francisco, Ian Toth, Shinji Tsuyumu, Jacquie van der Waals, Jan van der Wolf, Fr´ed´erique Van Gijsegem, Ching-Hong Yang, Iris Yedidia (2012) The role of secretion systems and small molecules in soft rot Enterobacteriaceae pathogenicity. Annual Review of Phyotopathology. 50. doi: 10.1146/annurev-phyto-081211-173013
My Publications
Theron, E, van Niekerk, JM, van der Waals, J.E.. (2026) In vitro phosphonate sensitivity of South African citrus Phytophthora nicotianae isolates. Acta Horticulturae 10.17660/ActaHortic.2026.1448.69
Alabi, GO, Maharaj, V, van der Waals, J.E., Invernizzi, L, Coutinho, TA. (2026) Managing Brown Rot Disease of Citrus Fruit Using Plant Extracts. Journal of Phytopathology 10.1111/jph.70254
Cruywagen, EM, Sutherland, R, Nkosi, BZ, van der Waals, J.E., Truter, M. (2026) Multiple large and small-spored Alternaria species causing leaf spot of potato in South Africa. Journal of Plant Pathology 10.1007/s42161-025-02082-y
Theron E, van Niekerk JM, van der Waals JE. (2025) A review of the use of phosphonates in the management of Phytophthora nicotianae in citrus in South Africa. Phytoparasitica 10.1007/s12600-024-01234-7
Strydom RF, Wilson CR, Tegg RS, Balendres MA, van der Waals JE. (2024) Advancements in Spongospora subterranea: Current Knowledge, Management Strategies, and Research Gaps. Potato Research 10.1007/s11540-024-09701-8
Coutinho TA, van der Waals JE. (2024) Historical perspective on 120 years of agriculture: Highlights from research published in the SAJS. South African Journal of Science 10.17159/sajs.2024/18965
Liakos C, Ibanez V, Lebre P, Derie ML, van der Waals JE, du Toit L, Dutta B, Kvitko B, Cowan D, Coutinho TA. (2024) The Bacterial and Viral Communities Associated with OnionBacterial Bulb Rot. Phytobiomes Journal 10.1094/PBIOMES-11-23-0121-R
Gush SL, Lebre P, Coutinho TA, Cowan D, van der Waals JE. (2024) Disentangling Shifts in the Soil Microbiome of Potatoes Infected with Rhizoctonia solani Anastomosis Group 3-PT in Search of Potential Biocontrol Agents. Phytobiomes Journal 10.1094/pbiomes-06-23-0046-r
van der Waals JE, Kruger K. (2020) Emerging potato pathogens affecting food security in southern Africa: Recent research. South African Journal of Science 10.17159/sajs.2020/8055
