Biology and population fluctuation of broom corn aphids in Miyaneh region, Iran

Broom corn is one of the most important crops in Miyaneh region, Iran. Aphids are major pests of the crop and farmers use different chemicals to their control in several times. In this research, broom corn aphids were collected and identified. Population fluctuation of the aphids was also investigated by weekly sampling and their biological characteristics were studied using leaf cages. The results revealed that, there were two species including Schizaphis graminum and Rhopalosiphum maidis in broom corn fields. Population peak of S. graminum (mean number of 0.75 aphids per tiller) was observed in June and decreased rapidly in July. R. maidis appeared later than S. graminum, but it was the most injurious aphid species of broom corn during all growing season. R. maidis population and it’s honeydew covered some plants and caused necrosis so that it’s number reached more than 000 aphids per tiller. Mean number of this species reached to 4.75 aphids per tiller and then decreased rapidly. In laboratory studies, mortality rate of S. graminum and R. maidis on broom corn leaves was relatively low (. and 5.6 percent). Nymphs of both species matured in less than 0 days. Mean longevity and mean fertility of mentioned aphid species was 8. and. 6 days and 4.84 and 49.7 nymphs per female respectively. Mean generation time of S. graminum and R. maidis was also. and 0.9 days respectively.