<P> Because of their food preferences, fall armyworm larva can wreak havoc on a wide range of human crops . The first historical account of the fall armyworm's destruction was in 1797 in Georgia . Destruction can happen almost over night, because the first stages of a caterpillar's life require very little food, and the later stages require about 50 times more . Because of this rapid change in food consumption, the presence of larva will not be noticed until they have destroyed almost everything in as little as a night . Some examples of targeted crops include cotton, grass, tobacco, sweet corn, rice, peanuts, and even fruits such as apples, oranges, and many more . The list of possible food sources for the worms is extensive, so crop damage is wide ranging . It is estimated that almost 40% of those species that armyworms target are economically important . Because the larva eat so much of the plant, they are very detrimental to crop survival and yield . In corn, larvae will even burrow into the corn ear to eat the kernels . </P> <P> Because of their great destruction, farmers must go to great lengths to deter fall armyworms . Insecticide is a widely used form of protection; in Southern regions farmers may have to apply insecticide to corn every day . Another strategy is planting crops earlier, because armyworm numbers increase as the summer progresses . </P> <P> In early 2017 armyworms infested large swathes of corn crops across Southern Africa, devastating the livelihood of many farmers . It is thought they arrived as an invasive species from the Americas as armyworm eggs in imported produce . Many African countries have agreed to take urgent actions against armyworms . </P> <P> S. frugiperda cells (Sf9 and Sf21 cell lines) are commonly used in biomedical research for the purpose of recombinant protein expression using insect - specific viruses called baculoviruses . </P>

What is the life cycle of army worms