Agricultural biocontrol — Wolbachia for crop pest management

The pest

The brown planthopper is the most destructive insect pest of rice in Asia.

Nilaparvata lugens damages rice in two ways. It feeds directly on the plant and at high densities causes hopperburn, where whole stands wilt and collapse. It also transmits Rice ragged stunt virus (RRSV) and Rice grassy stunt virus (RGSV), two diseases that can devastate a harvest.

Control has historically relied almost entirely on synthetic insecticides. That strategy is increasingly undermined by widespread pesticide resistance, leaving farmers with fewer effective tools each season.

It is precisely the kind of problem Wolbachia biocontrol is suited to: a sap-feeding insect that multiplies rapidly and carries plant pathogens, where suppressing the population and blocking the virus matter equally.

Brown planthopper (Nilaparvata lugens) on a leaf

Published evidence

First

Stable Wolbachia introduction into a hemipteran crop pest, a result not previously achieved.

wStri

Strain used. Showed high cytoplasmic incompatibility and drove rapid invasion through laboratory populations over successive generations.

2

Viruses spread by the pest. wStri inhibited Rice ragged stunt virus (RRSV) infection and transmission, and mitigated virus-induced symptoms in the rice plants themselves.

Current Biology · 2020 · doi.org/10.1016/j.cub.2020.09.033 ↗

A scientific first

In 2020, our science team published the first demonstration of its kind.

The study showed that a Wolbachia strain (wStri) could be stably introduced into the brown planthopper, where it behaved exactly as the principle predicts, and went further by protecting the plant itself.

"...the first novel stable artificial Wolbachia infection of a hemipteran insect, N. lugens. Importantly, this novel Wolbachia infection... has characteristics suitable for pest and disease control."

Current Biology · 2020 · doi.org/10.1016/j.cub.2020.09.033 ↗

The three outcomes

1

Establish

wStri was stably introduced into the brown planthopper, a hemipteran crop pest long considered difficult to infect with Wolbachia.

2

Spread

The strain showed high cytoplasmic incompatibility, driving rapid invasion through laboratory populations over successive generations.

3

Protect

wStri inhibited infection and transmission of Rice ragged stunt virus (RRSV), and mitigated virus-induced symptoms in the rice plants themselves.

What this means

The same two effects that make Wolbachia valuable against mosquitoes appear here together: incompatibility that can suppress or replace a population, and pathogen blocking that interrupts transmission.

What is new is the host and the target. The pathogen being blocked is not a human disease but a plant virus, and the beneficiary is the rice crop. It is the first demonstration of Wolbachia-mediated plant-virus inhibition in a rice pest.

Where this goes

A foundation for the next use case, handled with the same honesty as our mosquito work.

Stage of work

This is early-stage research. The results above are peer-reviewed laboratory findings, and we would design any programme alongside agricultural and regulatory authorities.

The same rearing infrastructure, strain science, and quality control behind our mosquito programmes provides a meaningful head start for this new target.

Next steps

1.

From lab to glasshouse

Replicate invasion and virus-inhibition results in contained glasshouse conditions on rice plants under realistic pest pressure.
2.

Partner with agricultural agencies

Work with ministries of agriculture and rice-research institutes to assess feasibility, biosafety, and fit within integrated pest management.
3.

Shared platform

Rearing, strain science, and quality control draw on the same infrastructure behind our mosquito programmes, a head start for a new target species.

The same biology that suppresses mosquitoes can protect crops.

The brown planthopper is the most destructive insect pest of rice in Asia.

In 2020, our science team published the first demonstration of its kind.

A foundation for the next use case, handled with the same honesty as our mosquito work.

Exploring crop protection? Let's discuss a pilot.