A field trial was carried out during 2008 and 2009 summer
seasons at the Experimental Farm of the Faculty of Agriculture,
Fayoum University. The aim work was to study the effect of
farmyard manure (FYM) and mineral N fertilizers on yield and its
components of "TWC310" maize hybrid. Three FYM rates, i.e., 15
(M1), 30 (M2) and 45 (M3) m3/fed. and three levels of mineral
nitrogen, i.e., 90 (N1), 120 (N2) and 150(N3) kg N/fed. of ammonium
nitrate were examined. The field was prepared as recommended and
the experiment was laid out in a split plot arrangement in RCBD with
four replications. Results revealed increasing positive response of
maize to FYM up to the largest amount of M3 that seemed to be large
enough to release N throughout the growing season and produced the
highest values of all the studied traits. The second rate of FYM (M2)
showed similar values for some traits which initiated at early time of
development. Whereas, the smallest rate of FYM produced relatively
inferior trait values. Grain yield of M3 surpassed those of M2 and M1
by 5.24 and 16.61%, respectively. Intermediate mineral fertilizer (N2)
application produced the tallest plants with the highest ear position.
However, N3 resulted in superior values of other traits, with
insignificant differences for grain weight/ear and grain yield/faddan
of those of N2. Grain yield produced with M1, M2 and M3 of FYM
applications were respectively comparable to those of N1, N2 and N3
indicating that mineral fertilizer (N) could be replaced by FYM in
such soil. The N1 application combined with either M2 or M3
improved plant and ear heights. The M2N3 and M3N3 interactions
were of the highest and had similar effects on ear weight (92.63 and
90.88g) grain weight/ear (75.88 and 72.13g) and grain yield/faddan
(1745.1 and 1658.9 kg). The M3N2 and/or M2N3 combinations
produced higher grain yield than those of sole application of either
organic or inorganic N fertilizer.