Abstract

Water availability influences seedling growth and rhizosphere bacterial communities in nursery systems. This study evaluated the effects of watering frequency on growth, leaf development, biomass characteristics, and cultivable rhizosphere bacterial populations of Terminalia ivorensis seedlings during a 42-day nursery experiment. Twelve seedlings were assigned to daily watering and watering every four days, with six seedlings per treatment. Height, collar diameter, leaf characteristics, leaf biomass, moisture content, dry matter, and bacterial abundance were monitored at seven-day intervals, while isolates were provisionally characterized using cultural, morphological, and biochemical methods. Initial measurements were comparable, with seedling height of 42.50 ± 7.04 cm and 44.00 ± 7.45 cm, respectively, and identical leaf numbers of 314.50 ± 62.49. By day 42, daily watering produced greater height (61.00 ± 2.86 cm), collar diameter (12.50 ± 1.51 mm), and leaf number (554.50 ± 99.00) than four-day watering (54.50 ± 13.02 cm, 8.00 ± 0.76 mm, and 411.50 ± 1.00, respectively). Daily watering also increased leaf length, width, individual leaf area, and total leaf area. Fresh and dry leaf biomass, moisture, and dry matter did not differ significantly. Bacterial abundance increased to 1.61 × 10⁷ CFU/g (7.21 Log₁₀ CFU/g) under daily watering but declined to 8.50 × 10³ CFU/g (3.93 Log₁₀ CFU/g) under four-day watering. Bacillus spp. predominated among recovered isolates, although bacterial genus distribution did not differ significantly between treatments.  Principal Coordinates Analysis demonstrated separation between watering regimes-(94.52% of variation). Findings indicate that consistent water availability promotes vegetative development and maintains higher rhizosphere bacterial abundance during nursery establishment.