Competition between larvae of Sitophilus oryzae (L.) and Sitotroga cerealella (Oliv.) within sorghum grains was studied at 30°C and 70% r.h. Newly hatched S. cerealella larvae (0 - 24 hr) were allowed to infest single sorghum grain having one S. oryzae egg deposited either on the endosperm half or the germ half. S. cerealella larvae were obtained from eggs of the same age as those of the weevil. The moth larvae entered the grain through the germ half. When S. oryzae egg was deposited in the germ half, S. cerealella survival probability was 0.78. However, when S. oryzae egg was deposited in the endosperm half, S. cerealella survival probability was 0.47. When the data for the two sites were combined the probability that the moth larvae will survive competition (P = 0.58) was not significantly different from that of the weevil. Hence, both larvae have similar chances of surviving competition within the sorghum grain.
