This study aimed to determine the growth of leaves and roots in the pakcoymustard (Brassica rapa) using hydroponic system with the AB Mix nutrition fertilizer. The data analysis used was to measure the number of leaves (Jd), leaf width (Ld), leaf length (Pd), number of roots (Ba), root length (Pa), and plant weight (Bt). Plant tools and media used were pipes, net pots, panel cloth, rockwool, TDS/EC, and water. The results of the analysis showed that the treatment of AB Mix nutrition gave a significant effect on the meter observing the number of leaves, leaf width, leaf length, number of roots, and root length. At the age of one week the number of leaves consists of three, leaf width: 0.5 cm, leaf length: 1.5 cm, there are 3 roots with the root length: 1 cm. At the age of two weeks, the number of leaves consists of 6, wide: 2 cm, long: 5 cm, there are 5 roots with the long: 3.5 cm. At the age of three weeks the number of leaves consists of 9 leaves, wide: 4 cm, long: 8 cm, there are 9 roots with the long root: 7.5 cm. At the age of four weeks the number of leaves consists of 11 leaves, leaf width: 8 cm, leaf length: 12 cm, there are 13 roots with the root length is 12 cm and a weight plant is 100 gram/plants to use AB Mix nutrients. It is showed that the growth and development of mustard pakcoy ( Brassica rapa ) hydroponic system with AB Mix nutrition has a significant effect on the growth of leaf number (Jd), leaf width (Ld), leaf length (Pd), number of roots (Ba), root length (Pa) and plant weight (Bt).

Acid sulphate soil has several problems such as low pH, low P-availability, and high solubility of Al. Efforts to optimize the productivity of acid sulphate soils are through the utilization of tolerant acid sulfur plants, soil microorganisms and organic fertilizers. This study aims were to determine the effect of applying azolla and the solubilizing phosphate bacteria on the growth and production of paddy (Oryza sativa L.) on acid sulphate soil. This research was conducted in greenhouse of Faculty of Agriculture, University of Sumatera Utara, from September to December 2017. The design used was factorial randomized block design with 4 replications. The first factor was fresh azolla with 4 levels viz A0=0, A1=30, A2=60 and A3=90 g/pot and the second factor was solubilizing phosphate bacteria with 2 levels,viz P0 = without solubilizing phosphate bacteria and P1 = application of solubilizing phosphate bacteria. The results showed doses of azolla 90 g/pot increased the growth of paddy, however the highest was found at treatment azolla with dosage 30 g/pot. Application of solubilizing phosphate bacteria increased the growth and production of paddy. Application 60 g fresh azolla/pot and inoculation of solubilizing P bacteria was the best treatment treatment that is (number of tiller 4 tiller, number of panicle 8,25 panicles, total grain amount 272,5 grain, dry weight of dry grain 6,75 g, dry straw weight 18, 27 g).

Used cooking oil is oil that comes from two or more frying food ingredients. This used cooking oil produces methyl esters with glycerol as a by-product through a transesterification reaction. The goal of this study was to convert and utilize used cooking oil into glycerol, as well as to demonstrate the similarity of functional groups and components found in commercial glycerol using IR and GC-MS spectroscopy. The results of the study found that using cooking oil glycerol and commercial glycerol showed that there were similarities in the 1,2,3 propanetriol groups with retention times that were close to 9.6-10.3 minutes and 9.6-10.13 minutes. The IR spectrum showed the presence of OH, CH, C=O, and C-O groups as well as those found in commercial glycerol, and the glycerol content obtained was 90.17%