Effect of Pinching and Paclobutrazol on Growth, Flowering, Chemical Constituents, and Histological Features ofTecoma capensis(Thunb.) Lindl

Abstract

This work aimed to evaluate pinching and paclobutrazol effects on potted Tecoma capensis (Thunb.) Lindl plant growth, flowering, and chemical composition. Assessed the growth, flowering, and chemical characteristics of Tecoma capensis transplants treated with and without pinching and paclobutrazol foliar spray (0, 75, 150, and 200 mg/l). Pinching and paclobutrazol treatments, and particularly the combined treatment of 200 mg/l paclobutrazol with pinching, reduced plant height and improved branch growth and root parameters. After 150 days, leaf midrib anatomy measurements increased significantly with the application of 200 mg/l paclobutrazol and pinching compared to the controls. The highest flower numbers, flower fresh and dry weight, and show value were achieved with the combination treatment of pinching and 200 mg/l paclobutrazoL. In addition, leaf nitrogen, Phosphorus, potassium, total carbohydrates, total chlorophyll, and leaf phenol contents were statistically increased by the interaction between pinching and 200 mg/l paclobutrazol. Moreover, applications of paclobutrazol at 150 mg/l with pinching and 200 mg/l without pinching significantly increased all aforementioned parameters. Pinching and paclobutrazol treatments were effective for achieving desired growth patterns in Tecoma capensis plants, particularly with paclobutrazol concentrations of 200 mg/l.