She turns into a brown cyst by the end of plant growth season, as her external surface hardens and her internal parts die.

[5] The cysts can withstand harsh conditions and can be spread in soil, by agricultural machinery, by animals, by wind, by dust storms or other means.

The weather conditions and soil types are also an important factor, with infections being increased in damp, warm growing seasons.

[5] The symptoms of infection include stunting and yellowing of the visible parts of the plant which may give the crop an uneven appearance.

[7] The roots of infested plants develop a tangle of branches and swellings which are white when young but turn dark brown with age.