The results showed that the use of both susceptible wheat cultivars to wheat stem sawfly Cephus pygmaeus (NN25, 12167) beside a cultivated wheat variety (ICPW 13172) reduce damage proportion by European wheat stem sawfly to cultivated variety 7.2-18.
2% when the experiment was carried out within the cages and 2.6 to 5.9% in field conditions. While the variety 12167 affect negatively on the life and fitness of this insect compared with variety NN25 where it cause of killing most of the larvae within its stems (54.03% in 2011 and 70.72% in the 2012) during its development, It also reduced the fertility of females, which followed its development and emerged in the following season, it was significantly less than the fertility of female emerging of NN25. Where the average female fertility of NN25 in two seasons 47.48, 48.32 egg, while the
average fertility of female of 12167 in two seasons 28.32 and 28.36 egg.
This research was conducted in a field of wheat located at Suran
(20 kilometers to the north of Hama city). The aim was to study
the influence of wheat planting date on wheat stem sawflies
infestation levels.
The research showed that the early wh
eat seeding led to
breaking the synchronization between the sensitive wheat
development period suitable for the wheat stem sawfly infection and
the existence of the insects in the fields.
