Two field experiments were conducted during 2002/2003 and 2003/2004
winter growing seasons at EI-Salhia, Sharkia Governorate Egypt. The aim of this
investigation was study the response of four Egyptian wheat cultivars viz. Sids 1,
Sakha 93, Gemmiza 9 and Giza 168 to three nitrogen levels (60, 80 and 100 kg N.fad)
with three nitrogen split application (1/4 at sowing + 1/4 at tillering + 1/4 at Jointing .•.
1/4 at heading), (1/4 at sowing + 1/2 at tillering + 1/4 at Jointing) and (1/3 at sowing +
1/3 at tillering + 1/3 at Jointing) in newly cultivated sandy soils. A split-split plot design
with three replicates was used in both seasons. The results revealed significant
difference's among studied wheat cultivars in all studied traits. Over the two studied
seasons, grain yield/fad was significantly varied among cultivars. This was arranged in
descending order as follows, Sakha 93. Giza 168, Sids 1 and Gemmiza 9. Increasing nitrogen level from 60 to 100kg N/fad significantly increased all
studied characters, except harvest index in the second season. Splitting nitrogen rates into three equal doses (1/3 at sowing + 1/3 at tillering
+ 1/3 at Joining) caused an increase in all studied characters, except harvest index in
both seasons and over them. Grain yield/fad was significantly and positively
correlated with plant height, number of spikes/m² , spike length, number of
spikelets/spike, umber of grains/spike, 1000 - grain weight and straw and biological
yields/fad.