Modification Vegetative of Plant Height in Paddy After Pbz Application with Rice – Oil Palm Planting System

Paclobutrazol (PBZ) is one of the hormone that acts by inhibiting activity of biosynthetic pathway of GAs, resulting in retardation if internodes in paddy. The aim of this experiment to find out concentration of Paclobutrazol (PBZ) suitable application in paddy with planting rice-oil palm system. This research was conducted using Split Plot Design factorial in four replicated which main plot were varieties IR 64, Mekongga, Inpari Sidenuk and Ciherang, whereas sub plot were used to concentration of PBZ with  0, 200, 400 and 600 ppm and was applied at panicle initiation (PI). Paddy varieties were planted with transplanting after 3 weeks in the seedling. Measuring plant height was conducted at three times, before application, two weeks after application and at harvesting. The result was shown that plant height before application was no signifant for among varieties and concentration, unlike plant height at two weeks after application and harvest time, following increase of concentration PBZ, plant height was decreased and significantly, respectively. The reduction of plant height with concentration PBZ at 400 ppm was found to be optimum as compare that ones. There was no interaction between varieties and concentrations of PBZ