Effect of Boron Spray and BiO-NPK Application on Vegetative and Flowering Characteristics of Petunia (Petunia hybrida)

A factorial experiment was conducted at the nursery of the Agricultural Division, University of Kufa, during the 2024-2025 season. The study aimed to investigate the effect of foliar application of three boron concentrations (0, 50, and 100 mg.L⁻¹) and the addition of three BiO-NPK concentrations (0, 1, and 2 ml.L⁻¹) on the vegetative and flowering characteristics of petunia plants. The experiment used a randomized complete block design and lasted for four months. Eighty-one seedlings were transplanted into 3 kg plastic pots and placed in a wire house covered with a 25% shade net. The results showed a significant positive effect of both boron and BiO-NPK, with the highest concentrations of each alone (100 mg.L⁻¹ and 2 ml.L⁻¹, respectively) significantly increasing all vegetative and floral traits. A significant interaction effect was also observed, with the combined application of 100 mg.L⁻¹ of boron and 2 ml.L⁻¹ of BiO-NPK yielding the best results in all studied traits, outperforming all other treatments.