When farmers face pests that damage their crops, many turn to chemical sprays. They often do not realise that indigenous plant-based practices can protect crops naturally, and that pest-control solutions already exist within traditional farming knowledge.
The use of chemicals is one of the common ways of managing pests. However, these chemicals have negative effects on the environment, are expensive, and often unaffordable for small-scale farmers.
Yet, we have knowledge that was applied for centuries by local farmers to manage pests. Despite the existence of this alternative, we currently have limited records of these plants and how they are applied. In addition, evidence on how these plants exert their effects is often lacking.
One researcher who is bringing this knowledge to light is Dr Kutullo Nick Shai from the North-West University’s (NWU’s) Indigenous Knowledge Systems (IKS) Centre at the Mahikeng Campus.
Through research funding from the National Department of Agriculture via Agricultural Research Council Pretoria and National Research Foundation, the project was supported from 2022 to 2025.
Dr Shai’s project on IKS systems of plants used for crop protection, focuses on identifying plants that smallholder farmers use to control pests and diseases.
The research revealed that a variety of locally known plants contain natural compounds that help manage crop infections. Extracts from Eucalyptus diversicolor, commonly known as the Karri tree, Dichrostachys cinerea, commonly known as Sickle bush, and Manihot esculenta, commonly known as Cassava, were found to have strong antifungal properties that can inhibit harmful fungi affecting maize and other crops.
“These plants demonstrated measurable antifungal activity,” Dr Shai explains. “Their bioactive compounds could support eco-friendly pest control approaches.”
Natural solutions are healthier
He says overreliance on chemical pesticides has led to major environmental and economic concerns. “Prolonged use of synthetic chemicals harms soil and water quality and can make pests more resistant. Natural plant-based solutions can reduce these risks and support healthier farming systems.”
Dr Shai notes that indigenous knowledge plays a crucial role in understanding local ecosystems. “Communities have developed their farming knowledge through experience and observation. They know which plants work best under certain conditions. That wisdom is valuable and deserves recognition.”
By analysing the biological effectiveness of traditional plants, the study bridges local experience and modern science. “Combining scientific testing with what farmers
already know allows us to identify plants that can be developed further into safe and affordable pest control products,” Dr Shai says.
He believes this approach could strengthen food security while reducing pressure on the environment. “Farmers often face crop losses from pests and diseases. If they can use natural methods that are accessible and affordable, it benefits both farming communities and the environment.”
Dr Shai says further work will focus on identifying the specific chemical compounds responsible for the antifungal activity found in these plants. “Understanding how these compounds work can help in developing natural products for agricultural use.”
His research shows the value of integrating traditional wisdom with modern science to create sustainable agricultural solutions. “The knowledge of farmers is not outdated,” Dr Shai concludes. “It remains an essential part of finding answers to current challenges in food production.”
Dr Kutullo Nick Shai
