ESTIMATING THE DAMAGE CAUSED BY THE CORN STEM BORER, SESAMIA CRETICA LED. (LEPIDOPTERA: NOCTUIDAE) TO SOME MAIZE VARIETIES

A field study was conducted at the College of Agricultural Engineering at the University of Baghdad to assess the susceptibility of maize varieties (Baghdad, Fajr and Maha) to the corn stem borer, Sesamia cretica. The results showed that the varieties differed in their susceptibility to the corn borer, with a significant difference between the Baghdad variety, which was the most susceptible variety, and the other varieties. The highest infestation rate was 30.49% on the Baghdad variety, and the lowest infestation rate was 9.84% on the Maha variety. The highest percentage of dead heart was 17.63% on the Baghdad variety, and the lowest percentage was 12.57% on the Maha variety. The results showed that the Baghdad variety had the highest percentage of loss in plant height 16.86% , number of larvae 2.90 larvae/plant, number of tunnels 5.86 tunnel/plant, tunnel length 15.79 cm/tunnel, and percentage of excavated area 11.01%. The lowest percentages were for the Maha variety, which were 10.5%, 1.57 larvae/plant, 3.81 tunnel/plant, 9.24 cm/tunnel, and 6.51%, respectively.