Hostname: page-component-586b7cd67f-t7czq Total loading time: 0 Render date: 2024-11-22T20:15:09.384Z Has data issue: false hasContentIssue false

Soil fertility management for organic rice production in the Lao PDR

Published online by Cambridge University Press:  15 March 2007

W. Roder*
Affiliation:
CIP/CFC, PO Box 670, Thimphu, Bhutan.
S. Schürmann
Affiliation:
Swiss College of Agriculture, Zollikofen, Bern, Switzerland.
P. Chittanavanh
Affiliation:
Project for the Promotion of Organic Farming and Marketing in Lao PDR, Vientiane, Lao PDR.
K. Sipaseuth
Affiliation:
Project for the Promotion of Organic Farming and Marketing in Lao PDR, Vientiane, Lao PDR.
M. Fernandez
Affiliation:
Project Promotion of Organic Rice from Lao PDR, Vientiane, Lao PDR.
*
*Corresponding author: [email protected]

Abstract

Rice is the most important agricultural commodity of the Lao People's Democratic Republic (Lao PDR), produced largely using traditional methods with limited inputs of fertilizers and other chemicals. The country has a wide diversity in rice production systems and rice varieties, with over 3000 different varieties recorded. The rich diversity and the production environment and methods are favorable for organic rice production. Investigations were carried out to describe soil fertility conditions, management practices, opportunities and problems associated with organic production methods for rice. Soils used for rice production are mostly of low fertility, with low organic matter and N-availability. In spite of this, virtually no fertilizer inputs are used for upland rice production. Inorganic fertilizer inputs for lowland rice production have increased rapidly over the past decade, but are still below 20 kg ha−1. The most important nutrient sources are rice straw and manure from buffalo and cattle. Chromolaena odorata plays an important role in nutrient cycling in upland rice systems and is sometimes added to lowland fields. In a range of fertility management studies, yield increase ranged from 2 to 89% for manure, straw or rice husk applied at modest rates (3 t ha−1), 32–156% for modest rates of inorganic fertilizer (60 kg N ha−1) and 36–167% for combined application of manure or crop residues with inorganic fertilizer. The response to locally produced commercial organic fertilizer was poor. The most promising inputs and strategies available to optimize yields in organic rice production systems are (1) optimizing use of locally available nutrients, mostly from manure, crop residues and weed biomass, (2) N addition through green manure and legumes growing in rotation and (3) additions of P through guano or rock-phosphate. The Lao PDR is fortunate to have substantial bat guano deposits in limestone caves. Extensive experience is available on straw and husk management for lowland systems and green manure species for upland production systems.

Type
Research Article
Copyright
Copyright © Cambridge University Press 2006

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

1 National Statistical Center. 2005. Statistics Lao PDR 1975–2005. Committee for Planning and Investment, National Statistics Centre, Vientiane.Google Scholar
2 Schiller, J.M., Rao, S.A., Hatsadong, P.H., and Inthapanya, P. 2001. Glutinous rice varieties of Laos, their improvement, cultivation, processing and consumption. In Chaudhary, R.C. and Tran, D.V. (eds). Specialty Rices of the World: Breeding, Production and Marketing. Science Publishers, Enfield, NH. p. 1934.Google Scholar
3 Chittanavanh, P., Sommani, P., Sanaphanh, K., and Roder, W. 2005. Opportunities for organic products in Vientiane— perceptions of consumers and traders Consumer and trader awareness and interest. In Proceedings of the IFOAM Organic World Congress, Adelaide, South Australia.Google Scholar
4 Raupp, J. 2001. Zwanzig Jahre Langzeit-Düngungsversuch. Oekologie & Landbau 118(2):2931.Google Scholar
5 Mäder, P., Fliebach, A., Dubois, D., Gunst, L., Fried, P., and Niggli, U. 2002. Soil fertility and biodiversity in organic farming. Science 96:16941696.CrossRefGoogle Scholar
6 Lao-IRRI. 1996. Annual report. Lao-IRRI, Vientiane.Google Scholar
7 Lao-IRRI. 1997. Annual report. Lao-IRRI, Vientiane.Google Scholar
8 Lao-IRRI. 1998. Annual report. Lao-IRRI, Vientiane.Google Scholar
9 Lao-IRRI. 1999. Annual report. Lao-IRRI, Vientiane.Google Scholar
10 Lao-IRRI. 2000. Annual report. Lao-IRRI, Vientiane.Google Scholar
11 Lao-IRRI. 2001. Annual report. Lao-IRRI, Vientiane.Google Scholar
12 Lao-IRRI. 2002. Annual report. Lao-IRRI, Vientiane.Google Scholar
13 Lao-IRRI. 2003. Annual report. Lao-IRRI, Vientiane.Google Scholar
14 Lao-IRRI. 2004. Annual report. Lao-IRRI, Vientiane.Google Scholar
15 Linquist, B. and Sengxua, P. 2001. Nutrient management of rainfed lowland rice in the Lao PDR. International Rice Research Institute, Los Banos, the Philippines.Google Scholar
16 Pandey, S. and Sanamongkhoun, M. 1998. Rainfed lowland rice in Laos: a socio-economic bench-mark study. International Rice Research Institute, Los Banos.Google Scholar
17 FAO. 2005. FAOSTAT on-line statistical service. FAO, Rome, Italy. Available at Web site: http://apps.fao.org (verified 2006).Google Scholar
18 Roder, W. 2001. Slash-and-burn rice systems in the hills of northern Lao PDR: description, challenges and opportunities. International Rice Research Institute, Los Banos.Google Scholar
19 George, T., Magbana, R., Roder, W., Van Keer, K., Trébuil, G., and Reoma, V. 2001. Upland rice response to phosphorus fertilization in Asia. Agronomy Journal 93:13621370.Google Scholar
20 Fahrney, K. 1999. Research priorities for upland rice-based agroecosystems in northern Laos. Completion of Service Report. International Rice Research Institute, Los Banos.Google Scholar
21 Roder, W., Keoboulapha, B., Phengchanh, S., Prot, J.C., and Matias, D. 1998. Effect of residue management and fallow length on weeds and rice yield. Weed Research 38:167174.CrossRefGoogle Scholar
22 Roder, W., Maniphone, S., and Keoboulapha, B. 1998. Pigeonpea for fallow improvement in slash-and-burn systems in the hills of Laos. Agroforestry Systems 39:4557.CrossRefGoogle Scholar
23 Roder, W., Maniphone, S., Keoboulapha, B., and Fahrney, K. 2006. Fallow improvement with Chromolaena odorata in upland rice systems of northern Laos. In Cairns, M. (ed.) Voices from the Forest: Integrating Indigenous Knowledge into Sustainable Farming. RFF Press, Washington, DC. Chapter 14. p. 146157.Google Scholar
24 FAO. 2004. Report of National Workshop on outcomes and impacts of the LAO-FAO TCP/LAO/2901 (A). Promotion of Organic Fertilizers at Plant Protection Center, Salakham. FAO, Field Document No. 9, Vientiane.Google Scholar
25 IFOAM. 2005. The IFOAM norms for organic production and processing. IFOAM, Bonn.Google Scholar
26 Goubeaux. 1930. Rapport agricole du Laos pour l'année 1929. Inspection générale de l'agriculture de l’élevage et des forêts, Hanoi, Vietnam.Google Scholar
27 Roder, W., Phengchanh, S., Maniphone, S., Songnhikongsuathor, K., and Keoboulapha, B. 1995. Weed management strategies aimed at reducing labor for upland rice production. In: Fragile Lives in Fragile Ecosystems. Proceedings of the International Rice Research Conference, February 13–17, 1995. International Rice Research Institute, Los Banos. p. 395405.Google Scholar
28 Roder, W. and Maniphone, S. 1998. Shrubby legumes for fallow improvement in northern Laos: establishment, fallow biomass, weeds, rice yield, and soil properties. Agroforestry Systems 39:291303.Google Scholar
29 Roder, W. and Maniphone, S. 1995. Forage legume establishment in rice slash-and-burn systems. Tropical Grasslands 29: 8187.Google Scholar