TECHNICAL


immediate situation derived, as it is, from directives, regulations, laws and legislation. However, with a little historical perspective it’s easier to see past the regulations and understand the bigger picture and why things are changing.


A brief history of pesticides…


Our knowledge of the earliest forms of pest control, after the development of agriculture approximately 10,000 years ago, is limited to the evidence that has survived to the present day. Nevertheless, we know that more than 4,500 years ago the Sumerians were using sulphur compounds to control insects and mites, that 3,200 years ago the Chinese were using insecticides derived from plants and, by


2,500 years ago, had appreciated the role of natural enemies and the value of adjusting crop-planting times to avoid pest outbreaks, and that the Greeks and Romans understood the use of fumigants, mosquito nets, granaries on stilts, sticky bands on trees and pesticidal sprays and ointments - although throughout this period and long beyond, such sophisticated practices were accompanied by widespread reliance on offerings to the gods and other superstitions. The Chinese continued to develop their pest-control technology and, by AD 300, they were using biological controls, establishing nests of ants in citrus orchards to control caterpillars and large boring beetles. Meanwhile, the Europeans, after the fall of


the Roman Empire, relied increasingly on religious faith rather than biological knowledge. This decline was reversed by the Renaissance, and the 17th century saw an awakening of interest in biological control and the rediscovery and/or introduction into Europe of a variety of natural pesticides (figure 1 overleaf).


The period from 1750 to 1880 in Europe was a time of the agricultural revolution, but this brought in its wake some of the greatest pest-driven agricultural disasters ever recorded: the potato blight in Ireland, England and Belgium (1840s); the epidemic of powdery mildew in the grape-growing areas of Europe (1850s); the outbreak of fungus leaf spot disease of coffee, after which Ceylon


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