Effect of Soil Moisture Content on Seedling Emergence and Early Growth of Some Chickpea (Cicer arietinum L.) Genotypes

At the crop level, the drought stress accounts for most variations in yield. A controlled glasshouse investigation at day/night temperatures of ۲۲/۱۵°C based at Perth City, Western Australia was performed (in ۲۰۰۶) 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 con-tent as the main treatment and genotype as sub-treatment. Significant differences (P < ۰.۰۰۱) as regards plant emergence and early growth were observed among different soil moisture contents (from ۱۰۰ to ۵۰, then to ۲۵% field capacity). This brought about a quad-ratic reduction in mean emergence percentage, delayed the first day to emergence and sup-pressed 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= - ۰.۸۷**) and above-ground biomass (r= -۰.۸۴**) 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 av-erage 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 reduc-tion in seedling parameters as compared to the resistant genotypes. Final average above-ground biomass (plant size) and plant height under the limited soil moisture content, as op-posed to adequate moisture level (F. C. ۲۵% vs. ۱۰۰%), were reduced ۷۹-۸۵% in Kabuli and ۷۷-۷۹% in Desi types, respectively.

Keywords:

Chickpea genotypes , Early seedling growth , Emergence percentage , First day to emergence , Soil moisture content