Effects of humic acid, paclobutrazol and boron on growth of tabernaemontana coronaria (crape jasmine)‎ plants

Abstract EN

A pot experimental study was carried out during the two successive seasons of 2019/2020 and 2020/2021to evaluate the effect of paclobutrazol (PP333) at 0.0, 20 and, 40 ppm, Humic acid (H) at 0.0 and 2gl^-1 and Boron(B) at 0.0, 2 and 4 mg/l on growth of potted Tabernaemontana coronaria plants.

The obtained data showed that: All PP333 and B concentrations decreased plant height, especially PP 333 at 40ppm in both seasons.

On contrary, all applied treatments of PP 333 and B significantly increased the root size, root and leaves fresh weight to reach its maximum by using humia acid at 2gl^-1, boron at 2 mg/l and 40ppm pp333-sprayed plants in the two seasons.

Furthermore, PP333 and B combined with H treatments significantly increased total chlorophylls contents as compared with un- sprayed plants in the two seasons.