Two field experiments were conducted at EI-Hamoul site, Kafr EL-Sheikh
Governorate during two successive seasons (1999/2000 and 2000/2001, where soil
salinity is the main environmental problem. The experimental materials consisted of
fourty-eight barley genotypes, three forms of nitrogen fertilization (Ammonium
sulphate, ammonium nitrate and urea) and two levels of nitrogen fertilization (70 and
105 kg N/ha).The objectives of this study were to investigate the interaction effects of
salinity and both forms and levels of nitrogen fertilization on yield of some barley
promising genotypes. Also, to select the best genotypes under saline condition, which
characterized by its low requirements of nitrogen fertilization under saline conditions.
The obtained results from the first season proved that applying ammonium nitrate
exceeded significantly both ammonium sulphate and urea in case of biological and
grain yield. The highest level of nitrogen' fertilizer produced the highest values of plant
height, biological and grain yields. Out of the fourty-eight genotypes tested under
saline conditions, nine genotypes were selected according to their performances
under saline condition. The selected nine genotypes produced higher biological and
grain yields than the rest of genotypes. Those selec ten entries were reevaluated
under same condition in the second growing season 2000/2001 with three national
checks; Giza 123, Giza 126 and Giza 2000. Obtained results from the second season
confied the results of the first one and proved that ammonium nitrate as nitrogen form
is recommended for saline soils. Genotypes evaluation under saline conditions and
fertilized with the lowest level of nitrogen fertilization revealed that four genotypes
exceeded significantly the national check Giza 123 in grain yield under the low level of
nitrogen fertilization. Also, the study of genotypic stability proved that two genotypes
seemed to be the most stable genotypes. Those genotypes are of great importance
for breeding to low requirements of nitrogen fertilization under saline conditions and
should be used in the national breeding program.