Harjono Harjono
Fakultas Kehutanan Universitas Gadjah Mada

Published : 3 Documents Claim Missing Document
Claim Missing Document
Check
Articles

Found 3 Documents
Search

Pengendalian Hayati Penyakit Akar Merah pada Akasia dengan Trichoderma S. M. Widyastuti; Sumardi Sumardi; A. Sulthoni; Harjono Harjono
Jurnal Perlindungan Tanaman Indonesia Vol 4, No 2 (1998)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/jpti.9901

Abstract

The experiment was aimed to measure the distribution and intensity of root rot disease of Acacia spp. in the urban forest at the campus of Gadjah Mada University, to isolate and identify the causal organism and to select Trichoderma sp. as biological agent for controlling the disease. The pathogenicity of the causal organism was tested using Crotalaria juncea L. and trunk of A. mangium Willd. (10 cm diameter, 8 cm length) as indicator plant. The ability of Trichoderma sp. as antagonist was tested in vitro. It was concluded that the pathogen of the root rot disease was Ganoderma philippii. The pathogen attacked for species of Acacia spp. in the location namely A. auriculiformis, A. mangium, A. oraria, and A. crassicarpa. Of the total individual trees of those species in the campus, as much as 38.6%, 22.2%, and 66.7% were attacked by the root rot pathogen respectively. Of the 20 Trichoderma spp. isolate capable to inhibit the pathogen in vitro, three isolates were found as promising agents for biological control of the pathogen. The promising isolates were T. resei/T23, T. koningii/T1, and T. koningii/T16 with inhibition effectivity of 94.58%; 93.66%; and 91.76% respectively.
Optimasi Produksi Endokitinase dari Jamur Mikoparasit Trichoderma reesei Harjono Harjono; Siti Muslimah Widyastuti
Jurnal Perlindungan Tanaman Indonesia Vol 7, No 1 (2001)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (6505.487 KB) | DOI: 10.22146/jpti.10021

Abstract

The objective of the experiment was to select optimal medium composition to induce endochitinase production of Trichoderma reesei. Growing media were prepared by substitution of 0.5% colloidal chitin, 0.5% colloidal chitin and 1% Polyvinyl Pyrrolidon (PVP), 1% crab shell chitin (Sigma), 1% crab shell chitin and 1% PVP into Richard’sMedium (RM). Selected bioagent T. reesei isolate 13 was grown onto the media and the specific activity of endochitinase was measured. The results showed that T. reesei grown in all media performed enzyme expression. The highest specific activity of endochitinase was detected on T. reesei grown in RM medium substituted with colloidal chitin and PVP, followed by the same fungi in RM medium substituted with crab shell chitin plus PVP, colloidal chitin and crab shell chitin alone.
Pemurnian dan Karakterisasi Enzim Endokitinase dari Agen Pengendali Hayati Trichoderma reesei Harjono Harjono; S. M. Widyastuti; S. Margino
Jurnal Perlindungan Tanaman Indonesia Vol 7, No 2 (2001)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (9594.734 KB) | DOI: 10.22146/jpti.10074

Abstract

This experiment was aimed to purify and characterize the endochitinase of Trichoderma reesei. Extracellular endochitinase was produced by T. reesei strain T13, a fungal biocontrol agent in colloidal chitin medium as sole carbon source. The enzyme was purified by ammonium sulfate precipitation, followed by gel filtration chromatography and chromatofocusing. The results showed that T. reesei produced endochitinase with molecular weight of 32 kDa and the activity was optimum at pH of 5,5 and temperature of 30 to 35oC.