06/12/2019
The African armyworm is a migratory moth, the larvae (caterpillars) of which are important pests of pastures and cereal crops, predominantly in Africa south of the Sahara, Yemen, and certain countries of the Pacific region.
Normally, only small numbers of this pest occur, usually on pastures. However, periodically the populations increase dramatically and mass migration of moths occur, covering many thousands of square kilometres and traversing international boundaries. They travel from field to field in great numbers, hence the name "armyworm".
Outbreaks follow the onset of wet seasons when dry grasslands produce new growth and cereal crops are planted. The severity and extent of outbreaks are increased by extended drought followed by early season rainstorms, which concentrate egg-laying moths and provide flushes of new grass as food for newly hatched caterpillars, and dry and sunny periods during the caterpillar development, which promote survival and rapid development. Therefore, major upsurges occur in seasons of sporadic rainstorms and long sunny periods throughout the outbreak period.
Caterpillars are major pests in outbreak years, causing significant losses on a local, national and regional scale. During outbreaks, caterpillars occur in such high numbers that they have to travel in masses from one field to another in search of food to complete their development, devastating crops as they move. Significant losses are most consistently reported from eastern and southern Africa. However, in recent decades, the frequency of reports from West Africa has increased, possibly due to the extension of suitable grassland habitats following forest and bush clearance for agriculture.
The economic importance of the African armyworm is due to its rapid development (short life cycle), high reproductive capacity, and mobility by migration. Moreover, there is little time to react as infestations frequently go unnoticed, since young caterpillars are difficult to detect.
What else would you lime to learn to know about army worm?