Effect of Water Stress on Growth Peformance of Synsepalum dulcificum (Schum. & Thonn.) Daniell Seedlings

Miracle plant (Synsepalum dulcificum) is an important protein sweetener with potential for use in a food industry. There is however the problem of its susceptibility to drought. The study was conducted to determine the effect of water stress on the growth performance of the seedlings. Seedlings were raised from seeds extracted from matured berries in a 30 cm × 19 cm polythene bags. Four months after planting, seedlings were subjected to three moisture regimes of 25%, 50%, 75% and compared with the control 100% (field capacity). Treatments were replicated five times and arranged in a Completely Randomized Design (CRD). The growth parameters measured were plant height, primary root length, number of leaves per plant, leaf area per plant, root and shoot dry weights at 7 days interval for 42 days. Dry weight and leaf area taken at 7, 21, 42 days (t1, t2 and t3) after application of treatments were used to calculate the Relative Growth Rate (RGR), Net Assimilation Rate (NAR) and Leaf Area Ratio (LAR). Data obtained were analysed using one-way analysis of variance (ANOVA). The RGR (0.0172 ± 0.0100 g¹ week⁻¹), NAR (0.0013 ± 0.0200 gcm^2–1 week⁻¹) and LAR (197.80 ± 0.01 cm² g⁻¹) obtained at 75% field capacity showed the fastest growth rate while the slowest growth rate was obtained at 25% field capacity with RGR (0.0077 ± 0.0100 g⁻¹ week⁻¹), NAR (0.0005 ± 0.0300 gcm^2–1 week⁻¹) and LAR (269.70 ± 0.01 cm² g⁻¹). Moisture regime of 25% field capacity significantly (P<0.05) reduced leaf area, number of leaves and total dry weight per plant. The study showed that S. dulcificum seedlings could be cultivated productively at 75% moisture regime.