The combination of plant growth regulators (GA3 and Gracilaria sp. extract) and several fertilisers in Salak Pondoh fruit production

Plant growth regulators (PGRs) and proper fertilisers are used to increase quality of the Salak Pondoh, such as in the plant production, fruit number and size. This study aims to determine the type and dosage of PGRs and the best type of fertiliser to increase the production bunch and fruit of Salak Pondoh. The method used was a Factorial Completely Randomised Design (FCRD) with 36 treatments (excluding the control) and 3 replications. Three treatments were conducted: first, as a control, no PGR treatment + fertilisation (no fertilisation, manure, and NPK). Second, a 3 × 3 factorial scheme. Treatment of PGR GA3 (50, 100, 150 ppm) + fertilisation (no fertilisation, manure, and NPK). Third, a 3 × 3 × 3 factorial scheme was used. Treatment of PGR Gracilaria sp. extract (50, 100, 150 ppm) with different solvents (n-Hexane, methylene-chloride, ethanol) + fertilisation (no fertilisation, manure, and NPK). The parameters observed were the number length, area of the bunch, length and area of the fruit. The results showed the highest number of bunches was found in PGR GA3 50 ppm. While, the highest bunch area was found in PGR Gracilaria sp. ethanol 150 ppm. The PGRs only increased the formation of the bunches and did not increase the length and width of the bunches and the fruit size. Fertilisation affected the Salak production in the form of the number, length and width of the bunches, and the fruit size. In addition, the fertiliser increased the number of the bunches, bunch area, and length and area of the fruit. The interaction of the PGR and fertilisation had no significant effect on increasing the Salak Pondoh production. The best result in increasing the Salak Pondoh production was PGR Gracilaria sp. ethanol 100 ppm with manure fertilisation.