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All Journal Journal of Tropical Soils Biota: Jurnal Ilmiah Ilmu-Ilmu Hayati
Shiddieq, Dja'far
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Agriculture, Biological Sciences & Forestry Biochemistry, Genetics & Molecular Biology Environmental Science

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Sekresi Asam-asam Organik oleh Aspergillus niger YD 17 yang Ditumbuhkan dengan Batuan Fosfat Sastro, Yudi; Widianto, Donny; Shiddieq, Dja'far
Biota : Jurnal Ilmiah Ilmu-Ilmu Hayati Vol 11, No 3 (2006): October 2006
Publisher : Universitas Atma Jaya Yogyakarta

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (446.464 KB) | DOI: 10.24002/biota.v11i3.2544

Abstract

Information on ability of Aspergillus niger to secrete organic acid is important in using A. niger as phosphate rock-solubilizing microorganism. This research was aimed to examine the ability of A. niger YD 17 secreting organic acid when it was grown with phosphate rock. An A. niger YD 17 was obtained from Laboratory of Microbiology, Faculty of Agriculture, GMU. The phosphate rock used was Christmas Island phosphate rock. Organic materials consisted of tapioca waste industry, rice bran, and starch. The study was conducted in Pikovskaya liquid medium and soils that were taken from Jasinga, Banten, West Java (ultisol) and Karang Jati, Ungaran, Central Java (inceptisol). The type and level of organic acid production were determined using high performance liquid chromatography (HPLC). The results indicated that A. niger YD 17 was able to secrete organic acid when it was grown with phosphate rock. The level of organic acid in the Pikovskaya liquid medium reached 255.7 g.ml-1, whereas in the soil reached 2992.5 g.g-1. Malate dominated organic acid in the Pikovskaya liquid medium, while in the soils dominated by oxalate. The type and level of organic acid secreted by A. niger YD 17 were influenced by carbon and phosphorus sources, concentration of inoculums, and characteristic of the soils.
Effect of Coated Urea with Humic-Calcium on Transformation of Nitrogen in Coastal Sandy Soil: A Soil Column Method Sulakhudin, Sulakhudin; Syukur, Abdul; Shiddieq, Dja'far; Yuwono, Triwibowo
JOURNAL OF TROPICAL SOILS Vol 15, No 1: January 2010
Publisher : UNIVERSITY OF LAMPUNG

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.5400/jts.2010.v15i1.11-18

Abstract

Effect of Coated Urea with Humic-Calcium on Transformation of Nitrogen in Coastal Sandy Soil: A Soil Column Method (Sulakhudin, A  Syukur, D  Shiddieq and T  Yuwono):  In coastal sandy soil, mainly nitrogen losses due to leaching resulted to low fertilizer efficiency. Slow-release N fertilizers are proposed to minimize these losses, and humic-calcium coated urea has been examined. A soil column method was used to compare the effects of coated urea with humic-calcium on transformation and leaching loss of N in coastal sandy soil. The experiment aid to compare two kind source humic substances (cow manure and peat) which mixed with calcium as coated urea on transformation, vertical distribution and leaching N in coastal sandy soil. The concentration of humic-calcium coated urea i.e.1%, 5% and 10% based on their weight.  The results showed that urea coated with humic-calcium from cow manure (UCHM) and humic-calcium from peat (UCHP) increased the N total and available N in the soil and decreased leaching loss of N from the soil column. Compare to UCHP, UCHM in all concentration showed N-nitrate higher than N-ammonium on incubation length 2, 4 and 6 weeks. The N leached from a costal sandy soil with application coated urea with UCHM ranged from 21.18% to 23.72% of the total N added as fertilizer, for coated urea with UCHP they ranged between 21.44% and 23.25%, whereas for urea (control) reach 29.48%. Leaching losses of mineral N were lower when urea coated with UCHM compared to urea coated with UCHP or urea fertilizer.  The study concluded that the UCHM is better than UCHP in decreasing N leached from coastal sandy soil.
Effect of Coated Urea with Humic-Calcium on Transformation of Nitrogen in Coastal Sandy Soil: A Soil Column Method Sulakhudin, Sulakhudin; Syukur, Abdul; Shiddieq, Dja'far; Yuwono, Triwibowo
JOURNAL OF TROPICAL SOILS Vol. 15 No. 1: January 2010
Publisher : UNIVERSITY OF LAMPUNG

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.5400/jts.2010.v15i1.11-18

Abstract

Effect of Coated Urea with Humic-Calcium on Transformation of Nitrogen in Coastal Sandy Soil: A Soil Column Method (Sulakhudin, A  Syukur, D  Shiddieq and T  Yuwono):  In coastal sandy soil, mainly nitrogen losses due to leaching resulted to low fertilizer efficiency. Slow-release N fertilizers are proposed to minimize these losses, and humic-calcium coated urea has been examined. A soil column method was used to compare the effects of coated urea with humic-calcium on transformation and leaching loss of N in coastal sandy soil. The experiment aid to compare two kind source humic substances (cow manure and peat) which mixed with calcium as coated urea on transformation, vertical distribution and leaching N in coastal sandy soil. The concentration of humic-calcium coated urea i.e.1%, 5% and 10% based on their weight.  The results showed that urea coated with humic-calcium from cow manure (UCHM) and humic-calcium from peat (UCHP) increased the N total and available N in the soil and decreased leaching loss of N from the soil column. Compare to UCHP, UCHM in all concentration showed N-nitrate higher than N-ammonium on incubation length 2, 4 and 6 weeks. The N leached from a costal sandy soil with application coated urea with UCHM ranged from 21.18% to 23.72% of the total N added as fertilizer, for coated urea with UCHP they ranged between 21.44% and 23.25%, whereas for urea (control) reach 29.48%. Leaching losses of mineral N were lower when urea coated with UCHM compared to urea coated with UCHP or urea fertilizer.  The study concluded that the UCHM is better than UCHP in decreasing N leached from coastal sandy soil.
Co-Authors Abdul Syukur Donny Widianto Sulakhudin Sulakhudin Triwibowo Yuwono Yudi Sastro