Pakistan Journal of Biological Sciences1028-88801812-5735Asian Network for Scientific Information10.3923/pjbs.2008.1234.1239SepaskhahA.R. GhasemiM.M. 92008119The water stress effects caused by every-other-furrow irrigation on
yield may be alleviated by more frequent irrigation intervals. This research
was conducted to determine yield and water use efficiency of grain sorghum
under fixed and variable every-other-furrow and every furrow irrigations
at different irrigation intervals and shallow and deep water table conditions.
Water needs of grain sorghum grown on a fine-texture soil may not be met
by using Every-Other Furrow Irrigation (EOFI) especially under 15 and
20 day irrigation intervals. The water stress decreased the grain yield
mainly through decreasing the number of grains per cluster and in a lesser
degree by decrease in 1000-seed weight. The clay soil with a layer of
high clay content at depth of 70-100 cm and shallow water table may restrict
the root growth and consequently the longer irrigation intervals with
greater soil water stress can cause lower grain yield in these conditions.
However, more frequent EOFI using 10 day intervals has produced very similar
results with only a marginal reduction in crop yield. Furthermore, there
was no statistically significant difference in grain yield between fixed
and variable every-other -furrow irrigations. In general, at given applied
water, the relative grain yield with respect to the maximum grain yield
of sorghum at EOFI was higher than those at EFI. At relative applied water
of 85% (mild deficit irrigation), EOFI may be recommended to obtain the
same grain yield as that of EFI with full irrigation. Furthermore, it
may result in 23% more grain yield than that obtained by EFI with the
same amount of applied water as deficit irrigation.]]>Doorenbos, J. and A.H. Kassam, 19791979Jensen, M.E.,1973pp: 215pp: 215Kashefipour, S.M. and A.R. Sepaskhah,199514203216Lyle, W.M. and J.P. Borodovsky,199538455462Samadi, A. and A.R. Sepaskhah,1984395115Sepaskhah, A.R. and A.A. Kamgar-Haghighi,1997347179Sepaskhah, A.R. and M.H. Khajehabdollahi,2005Zea mays L.).]]>8592600Sepaskhah, A.R. and A.R. Parand,2006Zea mays L.).]]>9415421Stone, J.F. and D.L. Nofziger,1993242738Tsegaye, T., J.F. Stone and H.E. Reeves,199357240245