Since 1940 the use of agrochemicals has increased dramatically, especially in the developed world and large scale producers in the developing world. Fungicides prior to 1940 were restricted to orchards, market gardening and vineyards, but are now used much more universally. The long term effects of fungicides and other agrochemicals is poorly understood, especially concerning the area of mycorhizal fungi and their symbiotic relationships with crops and other soil organisms which are vital in the roles of decay, nitrogen fixation, and the sulphur cycle.