EFEKTIVITAS PUPUK DAUN DAN WAKTU PEMBERIAN PACLOBUTRAZOL PADA STEK PLANTLET KENTANG (Solanum tuberosum L.) TERHADAP PRODUKSI TUBERLET KENTANG VARIETAS GRANOLA KEMBANG

The main obstacle in the production of potatoes is the lack of supply of high quality quantities of potato seeds. The availability of high quality potato seeds in Indonesia is only 7.4% far from the needs of 140,000 ton/year (including import), resulting in an average national production of only 12 ton/ha from the potential yield of 40 ton/ha. The solution of rapid propagation of high quality potato seeds is by way of propagation in vitro which will get disease-free plants and then acclimatization is done. This process is no less important in producing quality seeds. This study aims to determine the effect of foliar fertilizer and time of paclobutrazol on growth and production of tuberlet potatoes of Granola Kembang varieties. The experiment was conducted in greenhouses in Pujon Kidul village in July 2016 - November 2017. Experiments using Factorial Design were prepared in Group Random Design. Plant without treatment as a control. First factor, type of foliar fertilizer (2 ppm) (3 types of foliar fertilizer having different NPK composition is NPK 60%, NPK 20% and NPK 50%) Second factor, paclobutrazol (100 ppm) (30 HST, 35 HST and 40 HST). So obtained 9 treatment combinations and 1 control (P0W0) and each repeated 3 times. Each replication of each 5 samples of plants, So that the number of all samples used as much as 150 samples. Variant analysis done on the observations obtained and continued with 5% BNJ test if there is a real difference between treatments. Differences in the effects of control and treatment combinations were analyzed by Orthogonal Contrast Test. The results showed that foliar fertilizer with 20% NPK content combined with paclobutrazol when 40 days after planting resulted in the content of chlorophyll a, chlorophyll b, total chlorophyll and the best leaf area. Early paclobutrazol administration greatly reduces plant height and leaf count. The number of potato tubers per plant was generated at most on the administration of paclobutrazol when the plant was 30 days after planting with an average of 6.67 potato tubers. Paclobutrazol feeding on 30 days after planting combined with the type of foliar fertilizer with the content of NPK 60% and NPK 50 % produces more tuber class S (