Pengaruh Aplikasi Paclobutrazol dan KNO3 Terhadap Pertumbuhan dan Pembungaan Anggrek Tebu (Grammatophyllum speciosum blume)

The Grammatophyllum speciosum is a rare orchid and it is protected. It has a big clump, with the numbers of buds about 50-100 in each stem and its flower has yellow color with red brownish spots. The sugarcane orchid is very good to be used for the parent in producing hybrid orchid, however Grammatophyllum speciosum is very difficult to bloom, so that it requires a flowering induction. The objective of this research was to find out whether the paclobutrazol and KNO3 application can accelerate the flowering of Grammatophyllum speciosum. This research used completely randomized design with some factorials. The first factor was the concentrations of paclobutrazol of 0 mg.1-1, 1000 mg.1-1, 2000 mg.1-1, and 3000 mg.1-1. The second factor was the concentrations of KNO3 of 0 mg.1-1, 500 mg.1-1, 1000 mg.1-1, and 2000 mg.1-1. Each treatment combination was repeated three times. The treatment application was started from the 1 week orchid after the orchid was moved from one pod to another. The paclobutrazol spraying was conducted 4 times in 2 weeks interval, and KNO3 spraying was conducted 8 times in 1 week interval. The observation was made a day before application and 1 month after application. Variables to observe included numbers of vegetation, buds, vegetation height, bulb stem height, bud height, stem circumference, and numbers of leafs. The research result showed that the paclobutraziol and KNO3 applications were not able to induce flowering of Grammatophyllum speciosum. The treatment with 3000 mg.1-1 paclobutrazol was able to improve the stem circumference. Keywords : growth, flowering, Grammatophyllum speciosum, paclobutrazol, KNO3