الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
 |  | from | 148 |  |  |
| | | from | 148 | | |
Abstract
Planting dates, sorghum varieties and nitrogen fertilization were studied to see its effect on sorghum insects. The results showed that: the first planting date harboured the lowest mean number of aphid. H. zea: the results generally indicated that the differences between the 1st planting date and the two other planting dates were significant in both 2005 and 2006 seasons. The data clear that the infestation by R. maidis began at the same time in all tested genotypes.The maximum numbers of S. cretica larvae were found in all tested genotypes during the 4th week of July in 2005 season. The data clear that in both seasons of 2005 and 2006 Shandweel6 Hybrid was the highest susceptible genotypes for H. zea. Five nitrogen fertilization levels were studied (40, 70, 100, 130 and 160 units).