Sustainable Strategies for Enhancing Vegetative Propagation Efficacy and Yield in Sweet Basil (Ocimum basilicum L.)

Sweet basil (Ocimum basilicum L.) is an important aromatic, medicinal and culinary herb valued for pleasant fragrances and therapeutic properties. It is commonly used in perfumes, cosmetics, aromatherapy, flavoring, and herbal medicines. Vegetative propagation assures maintenance of desirable traits; however, rooting efficiency and initial establishment can be limiting factors. This study, carried out at College of Agriculture, Vellayani, Kerala Agricultural University, evaluated the influence of types of cuttings (terminal vs. semi-hardwood) and bioinoculants (arbuscular mycorrhizal fungi (AMF), Piriformospora indica, and plant growth promoting rhizobacteria consortium (PGPR Mix 1), on rooting, growth, and yield of sweet basil. A factorial experiment (2 × 3) was conducted using a completely randomized design. Semi-hardwood cuttings produced significantly longer roots and higher root biomass, whereas terminal cuttings developed more branches and yielded more fresh herbage and essential oil. Among the bioinoculants, P. indica significantly enhanced root number, root biomass, plant growth parameters, herbage yield, and essential oil yield, followed by AMF. PGPR Mix 1 exhibited comparatively lower performance. The interaction effects indicated that both the types of cuttings, when treated with P. indica, achieved superior rooting traits, plant growth, and oil yield. These findings suggest that use of either type of cuttings pretreated with bioinoculant P. indica, offers a practical approach for improving propagation efficiency and productivity in O. basilicum.