Cited research: PLoS Pathog. 6, e1000905 (2010)

The insecticidal bacterium Bacillus thuringiensis has been much used in biopesticides and its toxins are produced by many genetically modified crops. But little is known about the ecology of this soil- and plant-dwelling microbe.

Ben Raymond at the Royal Holloway University of London in Surrey, UK, and his colleagues studied a natural B. thuringiensis population in test cabbage fields. They found that an insect-killing strain, ST8, was the most common and the one most associated with plant leaves, where typical insect hosts feed. ST8 was also better than other strains at moving from soil to seedlings, showing specific adaptations.

The researchers demonstrate that the proportion of the population producing insecticidal toxins increased when more insect larvae were added. C.L.