During the 1960s Bennett worked at the (now-defunct) Scottish Plant Breeding Station, where she studied micro-evolution and the origins of genetic diversity, with a focus on forage and seed crops. Her work included expeditions around the world to collect plant samples.
In 1964 she wrote the internationally influential paper “Plant Introduction and Genetic Conservation: Genecological aspects of an urgent world problem”. In it, she coined the term "genetic resources" to express the idea that genes themselves are a resource - one that has been disappearing rapidly, as diverse traditional peasant seeds have been replaced by uniform modern, elite seeds.
In traditional, peasant crop varieties, or landraces, each plant is a bit different from the others, and this genetic diversity means that when new plant diseases or pests appear, at least some of the plants will likely be resistant. By contrast, in modern pedigree or elite crop varieties each plant is the same, and while these elite crops are often high-yielding, their lack of genetic diversity makes them particularly vulnerable to attacks by new strains of disease. When an elite variety stops giving acceptably high yields due to disease, or some other factor, the plant breeders turn to the traditional varieties, or even to wild relatives, in search of genes that can confer the necessary resistance.[1]
