Keywords : N fertilizer
journal of kerbala university,
Volume 13, Issue 1, Pages 171-177
A field experiment was carried out during the autumn season of 2015 in Abu Gharaq area, (10 km west of the Hillah city) to study the response of four maize genotypes to nitrogen fertilizer levels as whole or split application. Factorial experiment was carried out in split plot arrangement within randomized complete block design (RCBD) with three replications . Four genotypes of maize (US hybrid , Hispanic hybrid , Euphrates hybrid and popcorn ) put insub-plot and main main-plot included nitrogen fertilizer (urea 46%N) in five treatments (0 , 100 kg N.ha-1as whole or split application , 200 kg N.ha-1as whole or split application) . Maize genotype were differ significantly in most of the traits , popcorn was superior in plant height (186.03 cm), number of leaves (16.22 ) ,plant leaf area (6671 cm 2) , leaf area index (3.55). American hybrid was superior in stem diameter (15.07 mm) .Nitrogen fertilizer treatments were differ in their effect , in which 100 kg application as one timewas superior in plant height (161.05 cm). Nitrogen fertilizer treatments did not differ in number of leaves , leaf area , leaf area index, stem diameter , days number to 50% female flowering. The interaction between popcorn (surur var.) with the addition of 200 kg N.ha-1(as split application in two parts) in plant height (191.33 cm) and leaf area (6805 cm 2). And the same genotype with 100 kg N.ha-1(as whole) in the number of leaves (16.66) and leaf area index (3.7). American hybrid interaction with the addition of 200 kg N.ha-1(as split in two parts)was superior in stem diameter (15.40 mm).