Asian Journal of Crop Science1994-78792077-2041Asian Network for Scientific Information10.3923/ajcs.2014.142.149Abdel-MoneamM.A. SultanM.S. SalamaS.M.G. OrabyA.M. El 2201462A half diallel cross among 5 inbred lines of maize was evaluated under two
different nitrogen rates for yield and yield components characters i.e., ears
No. plant-1, ear length, ear diameter, 100-kernel weight, grain yield
plant-1 and shelling percentage to evaluate the role of GCA and SCA
of inbred lines in hybrids performance under normal and stress of nitrogen levels
and to establish the magnitude of heterosis. Mean squares of genotypes were
highly significant for all studied traits under both nitrogen levels, except
shelling percentage under normal nitrogen level. General and specific combining
ability (GCA and SCA) mean squares were significant or highly significant for
all studied traits, except shelling percentage under normal nitrogen level at
GCA and SCA. GCA/SCA ratios revealed that the non-additive gene action for all
studied traits under both nitrogen levels was detected. The best combiners were
P4 (Inb.204) and P5 (Inb.213) for most of studied traits
under normal and stress nitrogen levels. This result indicated that these inbred
lines could be considered as good combiners for improving these traits. The
best crosses for ears No. plant-1 were P1 (Inb.84) xP3
(Inb.144) and P3 (Inb.144) xP4 (Inb.204), for ear length
was P2 (Inb.95) xP4 (Inb.204), for ear diameter was P1
(Inb.84) xP5 (Inb.213), for 100-kernel weight was P2 (Inb.95)
xP4 (Inb.204) and for grain yield plant-1 was P1
(Inb.84) xP3 (Inb.144) under both nitrogen levels. These crosses
could be selected and used in breeding programs for improving these traits.
Results showed significant or highly significant heterosis over mid or better
parents for all studied traits, except shelling percentage under normal nitrogen
level. The best crosses over both their mid-parents and better-parent for ears
No. plant-1 was P3 (Inb.144) xP4 (Inb.204),
for ear length was P2 (Inb.95) xP4 (Inb.204), for ear
diameter was P1 (Inb.84) xP5 (Inb.213), for 100-kernel
weight was P2 (Inb.95) xP4 (Inb.204), for grain yield
plant-1 was P1 (Inb.84) xP3 (Inb.144) under
both nitrogen levels and for shelling percentage was P1 (Inb.84)
xP3 (Inb.144) under stress nitrogen level.]]>Abdel-Moneam, M.A.,20002000Abdel-Moneam, M.A., A.N. Attia, M.I. El-Emery and E.A. Fayed,200912433438Ahmed, M.A., M.H. El-Sheikh and S.A. Shamarka,20002537173726Akintoye, H.A., J.G. Kling and E.O. Lucas,199960189199Alamnie, A., M.C. Wali, P.M. Salimath and R.C. Jagadeesha,2006191316Al-Naggar, A.M., M.S. Radwan and M.M.M. Atta,20026179198Barakat, A.A. and M.M.A. Osman,20083346674679Dadheech, A. and V.N. Joshi,2007Zea mays L.).]]>41210214El-Absawy, E.A.,20022713631373El-Badawy, M.E.M.,2006Zea mays L.) over two years.]]>44911922El-Badawy, M.E.M.,20135113El-Hosary, A.A., M.K. Mohamed, S.A. Sedhom and G.K.A. Abo-El-Hassan,199432203215Gado, H.E., M.S.M. Suliman and M.A.K. Shalaby,2000Zea mays L) inbred lines.]]>2537693779Griffing, B.,19569463493Hoballah, A.A. and M.S. Radwan,1996Zea mays L.) by inbred and broad base testers.]]>2116391645Irshad-Ul-Haq, M., S.U. Ajmal, M. Munir and M. Gulfaraz,20104210211030Soares, M.O., G.V. Miranda L.J.M., Guimaraes, I.E. Marriel and C.T. Guimaraes,201142168174Raun, W.R. and G.V. Johnson,199991357363Sallah, P.Y.K., N.J. Ehlke and J.L. Geadelmann,19961996pp: 502507Sedhom, S.A.,199432119130