پديد آورندگان :
Siddique K. H. M. نويسنده , Palta J. A. نويسنده , Majnoun Hosseini N. نويسنده , Berger J. نويسنده
چكيده لاتين :
At the crop level, the drought stress accounts for most variations in yield. A controlled
glasshouse investigation at day/night temperatures of 22/15°C based at Perth City, Western
Australia was performed (in 2006) to assess the influence of different soil moisture contents
(field capacity percentage basis) on emergence as well as early plant growth in twenty
chickpea genotypes. The experiment was laid out in split plot design with soil moisture content
as the main treatment and genotype as sub-treatment. Significant differences (P <
0.001) as regards plant emergence and early growth were observed among different soil
moisture contents (from 100 to 50, then to 25% field capacity). This brought about a quadratic
reduction in mean emergence percentage, delayed the first day to emergence and suppressed
the early growth in all the chickpea genotypes. Highly significant differences were
also noticed among the genotypes for mean emergence percentage, first day to emergence,
plant height, leaf area, total above-ground biomass (plant size) as well as specific leaf area.
Significant interaction effect of soil moisture contents and genotypes were observed only for
some of the characteristics. Inverse relationship between first day to emergence with plant
height (r= - 0.87**) and above-ground biomass (r= -0.84**) were observed, indicating that
the chickpea genotypes which emerged sooner produced greater plant size. Seed size and
density were found to have no relationship with plant size. Although the Kabuli types on average
germinated faster and produced larger plants as opposed to the Desi types under the
limited soil moisture content, but there was no consistency observed among the chickpea
genotypes. Susceptibility of the genotypes to limited soil moisture condition was shown
through relatively longer delays in time to emergence (lower germination rate) and reduction
in seedling parameters as compared to the resistant genotypes. Final average aboveground
biomass (plant size) and plant height under the limited soil moisture content, as opposed
to adequate moisture level (F. C. 25% vs. 100%), were reduced 79-85% in Kabuli and
77-79% in Desi types, respectively.