In the early summer of 1968, farmers in Louisiana noticed small, elongated brown lesions running down green leaves of corn. These plants quickly died or experienced extensive rot that rendered the vegetable inedible. By 1970, these symptoms could be seen on acre after acre of corn from Florida to North Dakota. The disease soon had a name: southern corn leaf blight (SCLB). The fungal pathogen that caused SCLB, although virulent, could only infect a specific hybrid of corn. This hybrid, which was bred to develop a more efficient ear, was one of the most planted seeds in the country at the time. Once the cause of the vulnerability was discovered, seed companies simply switched hybrids. By 1972, the American corn market rebounded—although not before suffering major economic losses.
The world is now more cognizant of catastrophic biological risk. However, the focus is mainly on direct impacts to human health. The 1970 SCLB epidemic (technically termed epiphytotic) is a prime example of a fast moving plant disease that can inflict sudden and outsized damage to the agricultural industry. Is there significant biorisk to America’s food production and supply? In light of increasing food demand for a growing population and the easy conveyance of biological threats via global trade/travel, let’s explore potential biosecurity vulnerabilities in America’s agricultural industry and discuss possible solutions to mitigate these vulnerabilities.