No Blade of Grass (1970)

 No Blade of Grass (1970)

A strange new virus has appeared, which only attacks strains of grasses such 

as wheat and rice, and the world is descending into famine and chaos. Architect 

John, along with his family and friends, is making his way from London to his 

brother's farm in northern England where there will hopefully be food and safety 

for all of them. Along the way, they encounter hostile soldiers, biker gangs, 

and all manner of people who are all too willing to take advantage of travelers 

for a mouthful of food. (Jean-Marc Rocher IMDB)