Abstract

The declining natural regeneration of Pterocarpus santalinoides due to habitat degradation and crude oil pollution necessitates the development of efficient propagation techniques for its conservation and restoration. This study evaluated the influence of stem cutting length and soil condition on the vegetative regeneration of P. santalinoides under crude oil-contaminated and uncontaminated soils. The experiment was arranged in a Completely Randomized Design (CRD) with four stem cutting lengths (15, 25, 30, and 40 cm) and three replicates. Regeneration performance was assessed using sprouting percentage, mean sprouting time, sprout emergence, cumulative leaf length, and cumulative dry biomass. The 25 cm stem cuttings grown in crude oil-polluted soil consistently exhibited superior regeneration performance, recording the highest sprouting percentage (160%), mean sprouting time (0.71 days), cumulative sprout emergence (40 sprouts), cumulative leaf length (163 cm), and cumulative dry biomass (45.1 g). In contrast, the 30 cm stem cuttings generally exhibited the poorest regeneration performance. The findings demonstrate that P. santalinoides possesses considerable tolerance to crude oil-polluted soil during early establishment and that stem cutting length is a critical determinant of successful vegetative propagation. It is therefore recommended that 25 cm stem cuttings be adopted for nursery propagation and ecological restoration of crude oil-degraded environments, while further studies should evaluate their long-term field performance under varying levels of petroleum contamination.