Biology of the Spider Mite Eutetranychus sudanicus1

The biology of E. sudanicus Elbadry (Acarina: Tetranychidae) was studied in the greenhouse, using Citrus aurantiflora leaves, placed in petri dishes, as food. The incubation period averaged 5.7 and 4.3; larval period 3.7 and 2.9; protonymphal period 2.4 and 1.7; deutonymphal female period 2.7 and 2.2; and deutonymphal male period 2.4 and 2.0 days, in winter and summer, respectively. The preoviposition, oviposition, and postoviposition periods averaged 2.4 and 1, 12.2 and 10.4, and 3 and 2.4 days, in winter and summer, respectively. Fertilized fema0les laid an average of 22 and 32 eggs and lived an average of 15.2 and 12.8 days and males an average of 11.9 and 10.3 days, in winter and summer, respectively. The generation period lasted for 14.5 and 11.2 days in winter and summer, respectively. E. sudanicus had 27 generations per year. The sex ratio was 2.5 females:1 male.