Category: LW
Minimum Life Cycle: 25 days.
Distribution: Central America, parts of Africa. Thirty-four percent loss in maize after three to six months storage.
Biology:
Eggs - Laid in stored maize on the cob or bulk maize.
Larvae - Feed on grain.
Adults - Feed on grain.
a. Lesser grain borer.
b. Larger grain borer.
c. Larger grain borer (characteristic truncated posterier).
Larger Grain Borer (Prostephanus truncatus). The larger grain borer usually is restricted to corn (maize) and does not commonly occur north of Mexico. In recent years, new infestations have occurred in Africa. The insect is larger and darker in color than the lesser grain borer. It is extremely damaging to maize when dried and stored on the cob (Figure 5).
(Slide and top caption courtesy of GASGA Publication.)