Insects at the Frontline

How University of KwaZulu-Natal Research is Shaping Our Future

From sustainable pest control to pollinator conservation, discover how UKZN's entomology research is addressing some of South Africa's most pressing challenges.

Introduction

From the tiny pollinators that sustain our food systems to the crop-destroying pests that threaten agricultural economies, insects play an often invisible yet crucial role in human affairs. At the University of KwaZulu-Natal (UKZN), researchers are harnessing the power of entomology—the scientific study of insects—to address some of South Africa's most pressing challenges.

Pest Control

Developing innovative methods to protect vital crops from destructive insects.

Pollinator Conservation

Safeguarding essential pollinators that support our food systems.

Cutting-Edge Research

Combining traditional entomology with modern technology for sustainable solutions.

The work emerging from UKZN's laboratories and fields represents a fascinating convergence of traditional entomology with cutting-edge technology, offering sustainable solutions that balance ecological concerns with human needs.

Sugarcane Savior: Sterile Insect Technique to the Rescue

South Africa's sugarcane industry faces a formidable enemy: Eldana saccharina, commonly known as the African sugarcane stalk borer. This indigenous moth species wreaks havoc on gramineous crops including sugarcane, maize, sorghum, and millet across multiple African countries.

$60M+

Annual losses caused by the African sugarcane stalk borer in South Africa alone 1

1939

First major outbreak recorded in South African sugarcane 1

The South African Sugarcane Research Institute (SASRI), which has strong research connections with UKZN, has pioneered a revolutionary approach: using the Sterile Insect Technique (SIT) against this damaging pest 1 .

How SIT Works
Mass Rearing

Large numbers of target insects are reared in specialized facilities.

Sterilization

Insects are sterilized using precise radiation doses.

Release

Sterile insects are released into infested areas.

Population Control

Mating with wild insects produces no offspring, reducing pest populations over time.

What makes the approach to Eldana saccharina particularly innovative is the use of F1 sterility, a variation especially effective for moth species that tend to be radiation-resistant. Instead of completely sterilizing insects, researchers apply lower radiation doses that create "partially sterile" males 1 .

Inside the Groundbreaking F1 Sterility Experiment

The Methodology: A Step-by-Step Process

UKZN-associated researchers have developed a sophisticated protocol for implementing F1 sterility against the African sugarcane stalk borer.

Mass Rearing

The process begins with mass rearing of Eldana saccharina colonies under controlled laboratory conditions at SASRI. The insects progress through their complete life cycle—from egg to larva to pupa—in specialized rearing facilities 1 .

Transportation

The critical sterilization phase presents a unique challenge. In the absence of a local irradiator, researchers must transport pupae to a commercial SIT facility (XSIT) in Citrusdal, Western Cape—a journey of hundreds of kilometers 1 .

Irradiation

At the irradiation facility, emerging male moths receive a carefully calibrated dose of 200 Grays of gamma radiation—enough to induce the F1 sterility effect without significantly compromising their fitness or competitiveness 1 .

Release

These sterile insects are then released in target areas at overflooding ratios to ensure they outnumber the wild population, maximizing the chance that wild moths will mate with sterile counterparts rather than fertile ones 1 .

Results and Analysis: Promising Outcomes

The research has yielded exceptionally promising results. Confined cage experiments demonstrated that releasing sterile F1 moths at appropriate ratios significantly reduces crop damage caused by Eldana saccharina 1 .

Life Stage Radiation Dose Effect Application
Adult male 200 Grays Partial sterility Used for initial matings to produce F1 generation
F1 offspring Inherited effects Complete sterility Primary field release stage
F1 adults N/A (inherited) Normal fitness & competitiveness Effective mating with wild population

Table 1: Radiation Effects on Eldana saccharina at Different Life Stages 1

Perhaps most remarkably, researchers found that irradiation does not significantly affect the fitness of the F1 moths, meaning they can compete effectively with wild males for mates 1 .

Future Directions: Transition to X-ray Irradiation

Ongoing research is now focused on transitioning from gamma rays to X-ray irradiation for sterilization, part of a global initiative to replace radioactive sources with safer alternatives. This research, supported by Sandia National Laboratories, involves determining optimal dose positions and rates for X-ray irradiation and investigating its suitability for bulk processing 1 .

Parameter Gamma Irradiation X-ray Irradiation
Source Radioactive isotopes Electricity
Safety concerns Radioactive material handling No radioactive materials
Infrastructure requirements Significant regulatory requirements Less complex regulation
Effectiveness for Eldana Proven effective Under investigation

Table 2: Comparison of Irradiation Technologies for SIT 1

The Entomologist's Toolkit: Essential Research Equipment

The sophisticated research conducted at UKZN and partner institutions like SASRI relies on an array of specialized entomological equipment. These tools enable everything from basic insect collection to advanced reproductive studies.

Field Collection

Field Collection Equipment forms the foundation of entomological work. Insect nets with extendable aluminum handles and fine mesh bags allow researchers to capture flying specimens. For smaller insects, aspirators (sometimes called "pooters") create suction through gentle inhalation, safely drawing tiny specimens into collection chambers without damage 2 .

Laboratory Equipment

Laboratory and Rearing Equipment enables the maintenance of insect colonies for experimentation. Insect rearing cages provide controlled environments for studying life cycles and behaviors. These cages come in various configurations, including specialized designs like the green leaf hopper insect rearing cage made of teakwood with polished surfaces and fine mesh ventilation 2 .

Observation Tools

Observation and Analysis Tools are crucial for detailed examination. Magnifying glasses and dissecting microscopes enable close study of morphological features. Display cases with glass tops and airtight seals protect collected specimens from pests and environmental damage, often lined with insecticide strips to prevent infestation of preserved insects 2 .

Equipment Category Specific Tools Primary Function
Field Collection Insect nets, Aspirators, Light traps Capturing insect specimens from their natural habitats
Laboratory Maintenance Rearing cages, Climate chambers Maintaining insect colonies under controlled conditions
Specimen Preservation Killing jars, Preservation boxes, Pinning blocks Preparing and storing insect specimens for study
Observation & Analysis Magnifiers, Dissecting microscopes, Display cases Examining physical characteristics and behavior

Table 3: Essential Entomology Research Equipment 2

Beyond Pest Control: Pollinators and Sustainable Development

UKZN's entomological research extends far beyond agricultural pests. In a recent hybrid seminar co-hosted by UKZN's College of Agriculture, Engineering and Science and the South Africa Sweden University Forum (SASUF), researchers explored the critical role of pollinators in achieving Sustainable Development Goals 3 .

Bees and Food Security

Research presented by Vidushi Patel from the University of Western Australia highlighted that bees visit 90% of the world's top 107 edible crops, making them indispensable to global food security. Beyond food production, pollinators contribute to at least 15 of the 17 Sustainable Development Goals and 30 of their specific targets through ecological, economic, and cultural contributions 3 .

Evolutionary Solutions

UKZN's Professor Timo van der Niet presented his work on evolutionary-inspired solutions to the crop pollination crisis. By studying fundamental ecological and evolutionary processes in natural systems, researchers can develop innovative approaches to address pollination limitations in agricultural settings 3 .

"We are studying agriculture as a force for environmental change," explained Dr. Margarita López-Uribe of Penn State University. "So we are interested in understanding how the specific context of these agricultural systems not only shapes ecological interactions between pollinators and plants, but also the evolutionary trajectories of pollinators" 3 .

This pollination research highlights a crucial balance: while some insects like Eldana saccharina require control, others desperately need conservation. UKZN's entomology work addresses both priorities, developing sustainable pest management while protecting beneficial insects.

Conclusion: Small Creatures, Big Impact

The entomological research emerging from the University of KwaZulu-Natal demonstrates that insects are far more than simple pests or beneficial creatures—they are powerful tools for addressing complex challenges. From the sterile insect technique protecting sugarcane crops to pollinator research supporting sustainable development, UKZN scientists are showing how understanding insect biology and behavior can lead to innovative solutions.

Collaborative Approach

Perhaps most inspiring is the interdisciplinary and collaborative nature of this work. UKZN researchers regularly partner with international institutions, industry bodies, and government agencies, creating a rich ecosystem of knowledge sharing and innovation.

Training Future Scientists

As this research advances, UKZN continues to train the next generation of entomologists, ensuring that Africa will have the scientific expertise needed to balance insect management and conservation for years to come.

In the delicate dance between humans and insects, research institutions like UKZN play the vital role of choreographer, guiding us toward steps that benefit both people and the planet.

References