Response of Pigeon Pea Landraces [Cajanus cajan (L.) Millsp.] to Exogenous Application of Plant Growth Regulators

Aim: Optimizing plant growth regulators in the manipulation of growth physiology, development and seed yield of pigeon pea landraces is cardinal, especially as it complements other improvement techniques. The research was aimed at evaluating the effect of IAA, NAA and paclobutrazol singly and in combination, but especially paclobutrazol in reducing plant height.
Methods: Thirty (30) seeds each of brown “Fiofio” [Cajanus cajan (L.) Millsp.] were soaked in 0, 100, and 150mg/l concentration of IAA, NAA, paclobutrazol, paclobutrazol + IAA and paclobutrazol + NAA, respectively for 48 hours.
Results: Results obtained revealed that treating pigeon pea seeds with paclobutrazol caused reduction in plant height and inter-node length, which did not translate to higher yield. However, plants raised from pigeon pea seeds soaked in 100 and 150 mg/l paclobutrazol + NAA did excellently well in both yield and yield – related traits.
Conclusion: The implication of these findings is that though treating seeds with paclobutrazol caused significant reduction in plant height and increased branch numbers, it needed to interact with NAA to cause holistic improvement, especially in seed yield.