Influence of plant growth regulators and foliar nutrients on growth and yield of chilli

Application of growth promoters and stimulants containing plant growth regulators is a common practice among chilli farmers in Sri Lanka. An experiment was conducted in Yala season 2017 (minor season; May to September) and Maha season 2017/18 (Major season; October to February) to identify the influence of analytical grade plant growth regulators Gibberellic Acid (GA3), Naphthalene Acetic Acid (NAA) and one commercial product containing of 10% GA3, 6% Ca and 2% B, followed by Albert solution as a foliar nutrient spray, on growth and yield of hybrid chilli (Capsicum annuum L), variety MICH hy 1. The experiment consisted of two factors, (1) application of different plant growth regulators, i.e. T1 - 50 ppm GA3, T2 - 100 ppm GA₃, T3 - 50 ppm commercial product, T4 - 100 ppm commercial product, T5 - 50 ppm NAA, T6 - control with distilled water spray) and (2) two levels of Albert solution (with or without). The treatments were applied at the flower initiation stage. The Albert solution was applied three days after application of the plant growth regulator. Another dose of Albert solution was applied 20 days later. Application of GA₃ and the commercial product significantly increased the plant height and canopy width while it reduced the SPAD meter value, which is an indication of the chlorophyll content. Application of plant growth regulators did not influence the green chilli yield.