Two field experiments were conducted at Shandweel Research Station
sohagGovermorate, Agricultural Research Center, Egypt, during, summer season~ of
2002 and 2003, to study the performance of soybean genotypes namely: Ls, L_,2• Giza
111 and Clark under four plant population densities, i.e. 105, 140, 175 and 210
thousand plants per feddan using split-plot design.   Results showed that Giza 111 surpassed all the other tested genotypes in
number of branches, pods, seeds and seed yield per plant when sown at the lowest
population density (105.000 plants/fed). Seed yield per feddan significantly increased
by increasing plant density until (175.000 plants/fed.). Generally, increasing plant
density decreased yield components but increased plant height and seed yield per
feddan. Wheares plant height increased with the increase in plant density up to
(210.000 plants/feddan). The greatest yield of seed per feddan was achieved when
sowing Giza 111 cultivar with the population density of 175.000 plants/feddan .   Estimates of genotypic and phenotypic coefficients of variation reveald high
values in number of branches/plant, number of pods/plant, seed weight/plant, number
of seeds/plant and seed weight/plant. All the studied characters recorded high
heritability values (more than 50%). There was highly significant and positively
correlation between number of branches and each of number of pods/plant, number of
seeds/plant, seed weight/plant and 100 seed wight. Path coefficient analysis revealed
that plant height, number of seeds/plant and number of branches/plant had the most
prominent direct effects on seed yield/feddan with relative importance of 15.78%,
8.29% and 7.35%, respectively of the total variation of seed yield/feddan.