Evaluation of random dwarf (Rht) and tall (rht) wheat lines under irrigated (nonstress)
and rainfed (water stress) environments showed that Rhtl and Rht2 dwarfing genes
have negative effect on grain yield under water stress conditions. The greater decline
in the grain yield of Rht lines was due to significant and greater reduction in
biological yield caused by reduced number of lighter tillers and yield per spike
due to reduction in number of florets and grains per spike (Rhtl) or grain weight
(Rht2) and early maturity. It is concluded that the poor biological and grain yields
of Rht dwarf lines under water stress may emanate from their greater sensitivity
to the factors associated with diminished soil moisture content. However, in Rht
dwarf lines under water stress conditions, variability for stress susceptibility index
(S) and its negative association with grain yield were noted. This suggested that it
should be possible to select Rht containing semidwarf lines with high yield potential
and greater tolerance to water stress conditions.
Keywords: Wheat, Rht genes, pleiotropic effects, grain yield, sensitivity, water stress.
Year: 1998
Volume: 58
Issue: 2
Article DOI: NA
Print ISSN: 0019-5200
Online ISSN: 0975-6906
H. S. BALYAN AND R. S. LOHIA info_circle