Maturity stages and moisture content of sorghum grain damaged by maize weevil.

摘要

The maize weevil, Sitophilus zeamais Motschulsky, a major insect pest of stored grain, infests kernels in the field and is brought into storage where damage continues. To evaluate damage by maize weevils to different maturity stages of kernels of sorghum, Sorghum bicolor (L.) Moench, five adult weevils were put into each of 10 vials with 5 g of kernels collected from 'Pioneer 86G08' sorghum at different stages of maturity in the field. Statistically significant differences were found among the maturity stages of sorghum in the percentage of damaged kernels and numbers of live and dead maize weevils 7 days after infestation. At 7 days after infestation, 6.1, 15.4, 23.1, 17.4, 12.0, and 8.0% of the grains that had 50 (milk), 34 (soft dough), 32 (hard dough), 24, 16, and 14% moisture (physiological maturity), respectively, were damaged by maize weevils. Sorghum grain at the hard-dough stage (approximately 32% moisture) was most vulnerable to maize weevils.