The effect of carrier material and moisture potential on the quality of legume inoculants

Simanungkalit, R. D. M., Roughley, R. J . and Indrasumunar, A. (1999) The effect of carrier material and moisture potential on the quality of legume inoculants. Jurnal Penelitian dan Pengembangan Pertanian, 18 1: 64-70.

Author Simanungkalit, R. D. M.
Roughley, R. J .
Indrasumunar, A.
Title The effect of carrier material and moisture potential on the quality of legume inoculants
Journal name Jurnal Penelitian dan Pengembangan Pertanian
ISSN 0216-9959
0216-4418
Publication date 1999
Sub-type Article (original research)
Volume 18
Issue 1
Start page 64
End page 70
Total pages 7
Place of publication Bogor, Indonesia
Publisher Indonesia Agency for Agricultural Research and Development
Language eng
ind
Formatted abstract
Some experiments have been conducted in the Laboratory of Australian Inoculant Research and Control Services, Gosford, NSW, Australia and in the Soil Microbiology Laboratory of the Research Institute for Food Crops Biotecnology, Bogor, Indonesia to determine the effect of five Indonesian peat sources and their moisture potential on the quality of legume inoculants. Peat deposits from 5 swamps in Indonesia were sampled, milled, and their pH adjusted with lime using a pre-determined neutralisation curve. The pH of the carrier after equilibration was within the range pH 6.2-6.6 (CaCl2). The peat from Australia has the better moisture characteristic in requiring a greater loss of water to change their moisture potential to a level likely to affect rhizobia. To test the general suitability of these peats as carriers for legume inoculants, 40 g samples of each were packed in polyethylene bags and sterilised with 50 kGy gamma radiation. These were inoculated with Bradyrhizobium japonicum strain CB 1809 at a moisture potential of-log 10 4.5 Pa. While not necessarily the optimum for each carrier, it was a suitable compromise. The numbers of CB 1809 were counted. These inoculants were also used to test the survival of Bradyrhizobia inoculated onto polyethylene beads. With the exeption of lakbok peat, the other four Indonesian peat sources (Rawa Pening, Dieng, Rawa Jitu and Rawa Sragi) were suitable as carrier materials for Bradyrhizobia inoculants. From these experiments, peat from Rawa Pening was selected to determine the optimum moisture potential for CB 1809, USDA 110, and FCB 26. Treatments compared were -log 10 3.5 (Australian) 3.7 (Rawa Pening) 4.0. 4.5, 5.4 dan 6.0 Pa. At 4 weeks numbers of Bradyrhizobia depended on interactions between strain and moisture potential and between peat source and moisture potential. CB 1809 was the most sensitive strain at the least negative potential in comparison to USDA 110 and FCB 26. Numbers of CB 1809 were only 11.7 percent of the other strains and at that potential would fail Indonesia and Australian Quality control standards. All strains were more affected by differences in moisture potential when in Australian peat. The difference in numbers across moisture potentials at 4 weeks was log 10 0.88 for Australian peat and log 10 0.44 g-1 carrier for Rawa Pening peat.

Beberapa percobaan telah dilakukan di Australian Inoculant Research and Control Services (AIRCS) di Gosford, NSW, Australia dan Laboratorium Mikrobiologi Tanah Balai Penelitian Bioteknologi Tanaman Pangan, Bogor, Indonesia untuk melihat pengaruh berbagai sumber gambut dari Indonesia dan potensial kelembabannya terhadap daya hidup bradyrhizobium. Contoh gambut dari lima lokasi di Indonesia diambil, dikeringkan, digiling halus pHnya disesuaikan dengan pemberian kapur yang jumlahnya didasarkan pada kurva netralisasi yang sudah ditetapkan sebelumnya. Nilai kemasaman (pH) bahan pembawa setelah mencapai keseimbangan berkisar 6,2-6,6 (CaCl2). Gambut dari Australia memiliki karakteristik kelembabannya yang lebih baik karena membutuhkan kehilangan air yang lebih besar agar dapat mengubah potensial kelembabannya ke suatu tingkat yang mungkin mempengaruhi bradyrhizobia. Untuk menguji kesesuaian gambut-gambut ini sebagai bahan pembawa inokulan legum, contoh-contoh gambut seberat 40 g dibungkus dalam kantong polietilen lalu disterilisasi dengan gamma radiasi 50 kGy. Kantong-kantong ini selanjutnya diinokulasi dengan Bradyrhizobium japonicum strain CB 1809 dan potensial kelembabannya disesuaikan pada -log 10 4,5 Pa. Jumlah CB 1809 dihitung pada 14 dan 28 hari setelah inokulasi. Inokulan-inokulan ini juga dipakai untuk menguji daya hidup bradyrhizobia pada manik-manik polietillen. Kecuali gambut dari Lakbok, gambut dari empat lokasi lain (Rawa Pening, Dieng, Rawa Jitu, Rawa Sragi) sesuai untuk dipakai sebagai bahan pembawa inokulan legum. Dari hasil percobaan ini, gambut dari Rawa Pening dipilih untuk percobaan menentukan potensial kelembaban optimum bagi CB 1809, USDA 110 dan FCB 26. Perlakuan kelembaban yang diberikan adalah -log 103,5 (Australia), 3,7 (Rawa Pening), 4.0; 4,5; 5,4; 6,0 Pa. Pada umur 4 minggu jumlah bradyrhizobia tergantung pada interaksi strain x potensial kelembaban. CB 1809 merupakan strain yang paling sensitif pada potensial yang paling negatif (-log 10 6.0 Pa) dibandingkan dengan USDA 110 dan FCB 26. Jumlah CB 1809 hanya 11,7 persen dari kedua strain lain dan pada potensial tersebut jumlah ini tidak memenuhi standar mutu Indonesia dan Australia. Semua strain lebih dipengaruhi oleh perbedaan potensial kelembaban tertinggi dan terendah pada umur 4 minggu log 10 0,88 untuk gambut Australia dan log 10 0,44g-1 bahan pembawa untuk gambut Rawa Pening.
Q-Index Code C1
Q-Index Status Provisional Code
Institutional Status Unknown
Additional Notes Abstract only in Indonesian.

Document type: Journal Article
Sub-type: Article (original research)
Collection: Faculty of Science Publications
 
Versions
Version Filter Type
Citation counts: Google Scholar Search Google Scholar
Created: Thu, 24 Feb 2011, 13:41:42 EST by Dr Arief Indrasumunar on behalf of Central Glasshouse Services