Much of the credit for increased crop yields in the past 50 years has been assigned to the use of fertilizers. However, the full value of fertilizers can only be realized if crop pests are controlled. For example, without herbicides to control weeds, much of the fertilizer would simply be used up by weeds and the crops would not receive the full benefit. A UK researcher made this point in an article on 21st century crop improvements…

“Advances in agronomy have stemmed from the continued use of fertilizers, … the true value of which could only be realized in the presence of suitable varieties and in the absence of competition from weeds, pest and diseases. The latter protection of crops has depended on the developments of the agrochemical industry which has developed sophisticated chemical syntheses and screening technologies. … These improvements have brought large social gains, for example, in greater food security, lowering of malnutrition, lower prices freeing up income for other discretionary activities, vastly greater food choices, and safer foods…”

Author: Ben Miflin
Affiliation: IACR Rothamsted
Title: Crop improvement in the 21st century
Publication: Journal of Experimental Botany. 2000. 51(342):1-8.