Optical pest control: Study finds switching to red nets helps protect crops better

Embracing sustainable agricultural practices and seeking alternatives to chemical pesticides is crucial for the future of farming. (Photo credit: Tom Fisk via Pexels)

A study by researchers from the University of Tokyo has revealed that the colour of nets used to protect crops can drastically enhance their effectiveness in deterring pests. By switching to red nets, rather than conventional white or black ones, farmers can potentially reduce their reliance on pesticides while safeguarding their crops from destructive insects.

In the study, red nets were found to significantly suppress invasion rates and minimise damage (white spots on the leaves) caused by onion thrips—the main vector of the Iris Yellow Spot Virus and the Tomato Spotted Wilt Virus (TSWV) that cause serious damage to various vegetables. The research was conducted in a Welsh onion greenhouse with minimum use of pesticides.

Surprisingly, even when the mesh size of the red nets was larger, they outperformed traditional nets in both laboratory and field tests. This innovative approach, termed “optical pest control”, leverages insect colour vision and behavioural responses to provide more sustainable crop protection solutions.

The benefits of red nets extend beyond pest deterrence. In practical field trials, onion crops partially or fully covered by red nets required 25 percent to 50 percent less insecticide compared to unprotected fields. This reduction in pesticide use not only mitigates environmental impact but also supports more sustainable agricultural practices.

The study emphasises the economic viability of red nets. While they may initially cost more than pesticides, their long-term usability and effectiveness make them a cost-effective solution for farmers. They are also labour-saving. Additionally, red nets with larger mesh sizes offer improved breathability, reduced risk of fungal infections, and better sunlight penetration due to their larger holes.

Ultimately, embracing sustainable agricultural practices and seeking alternatives to chemical pesticides is crucial for the future of farming. With continued research and adoption of solutions like red nets, farmers can protect their crops effectively while minimising environmental impact and ensuring food security for generations to come.