A research entomologist at the South African Sugarcane Research Institute (SASRI), Mr Lawrence Malinga, can now add the honorific “Dr” to his name after graduating with a PhD in Plant Pathology.
Dr Malinga researched one of the world’s most important fibre crops – cotton – advancing sustainable approaches to managing the many factors that impact the production of the important crop, particularly major insect pests.
Cotton is highly susceptible to pest damage, and up to 80% of cotton harvests would be lost annually without the use of pesticides which account for 16% of global insecticide releases – more than any other crop.
The global challenge of reducing the use of chemical pesticides which have detrimental effects on human health and the environment drives investigations into biologically-derived pesticides, which could play a vital role in integrated programmes to address the production challenges that affect farmers’ profits.
Malinga worked at the Agricultural Research Council (ARC) as a researcher for 16 years, managing sustainable rural livelihood projects in three provinces. He was intrigued by the preliminary results emerging from his research projects on the biological control of cotton pests and decided to further this research through a PhD which he hoped would produce more information to aid farmers. He chose to study at UKZN for his doctorate because of the support offered to postgraduate students.
With the encouragement of colleagues, Dr Graham Thompson and the late Dr Habtom Tesfagiorgis from the ARC Institute for Industrial Crops, Malinga enrolled under the supervision of Professor Mark Laing who has extensive knowledge of biopesticides. He thanked Laing for his insightful feedback as well as his invaluable expertise, and Thompson for his encouragement and assistance.
In his thesis, Malinga unpacked the current status of pests on cotton and production practices in South Africa as well as evaluating the efficacy of biopesticides in comparison with conventional insecticides in the control of cotton pests under field conditions. The cost benefits of biopesticides compared to conventional agrochemicals was also an important aspect of Malinga’s research.
He hoped to reveal insights that would build a foundation for the management of major cotton insect pests. While the costs of combining a spectrum of biocontrol agents exceeded the costs of a single broad-spectrum pesticide, his findings will be significant in developing integrated programmes.
Malinga used the COVID-19 lockdown period to write up his thesis from which a peer-reviewed chapter and a book chapter have been published in international journals.
He says attaining his PhD will assist in his mentorship of postgraduate students and help his efforts in sugarcane research. At SASRI, he works on research, technology development and knowledge exchange projects that require entomological expertise in the control of sugarcane pests.
Malinga manages projects on Eldana sterile insect technique and biodiversity of non-target organisms on Bt and non-Bt sugarcane.
Malinga was born in Mkhondo, Mpumalanga, and completed his undergraduate studies in Entomology and Zoology and his Honours and Master’s degree studies in Entomology at the University of Fort Hare.
He is a reviewer for the Crop Protection journal and the American Journal of Agriculture and Forestry and IntecOpen Book Publisher, and a member of the Editorial Board of the Journal of Modern Agriculture and Biotechnology. He was a Southern and Eastern African Cotton Forum Secretary and currently serves on the Advisory Board for Biological Sciences at the University of the Free State. In addition to his peer-reviewed publications, he has presented numerous papers at local and international conferences.
Malinga thanked his mother, Ms Thembi Joyce, for being there for his family when he needed to travel and also thanked his wife, Thobile Lorraine, his daughter Laurencia Nomathemba, his son Stanley Unathi and his granddaughter Mbalenhle for their love, support and patience, without which, he says, he could not have completed his thesis.
Words: Christine Cuénod
Photograph: Abhi Indrarajan