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Seeds of hope Results of the System of Rice Intensification (SRI) in Cambodia have consistently proven that small farmers can increase rice production while reducing fertilizer, seed and water inputs. SRI has led to significant yield increases with both traditional and international rice varieties. Role of rice In Cambodia, rice is the main staple food, and rice farming provides income and an employment opportunity for around 65% of the population. Officially, the national average yield of rice is estimated to be between 1.65 and 1.80 tons per hectare in the wet season, (low compared with other countries in the region). During the last three decades, a great deal of effort has gone into improving traditional rice farming. This has focused on developing and disseminating recommendations for fertilizer applications, introducing improved, high-yielding varieties, and using integrated pest management. Rising costs Although this approach can help farmers to increase their yields, the environmental sustainability and economic advantages of this for small farmers and for Cambodia still remain an issue. Rice productivity is still relatively low compared to the growing demand, while farmers' costs of production are increasing, mainly due to the cost of fertilizer and fuel for pumping water. Finding solutions During the wet season of 2000 CEDAC(1), a Cambodian NGO working to develop and disseminate innovations in ecological agriculture, integrated the elements of SRI into their sustainable rice intensification program. This story summarizes CEDAC’s results and experiences of SRI adaptation in Cambodia and concludes with a perspective on its future. What is SRI? SRI seeks to increase rice production through the improvement of practices in plant, water, soil and nutrient management, rather than through the use of new or purchased inputs.(2) SRI discoveries go against some of the accepted beliefs in traditional and conventional rice farming. The main differences, especially in terms of water and plant management, are explained briefly as follows. A. Plant Management Rice plants by themselves have great natural potential to produce a lot of tillers (stalks) and grain when certain associated practices are employed. This was discovered by Father de Laulanié, a French priest living in Madagascar, and was proven by scientific experimentation conducted by Katayama, a Japanese scientist, in the 1920s and 1930s. Conventional management practices for transplanted rice seedlings suppress or ignore this capability while SRI practices help farmers to capitalize upon this biological potential effectively. (The model of rice tillering developed in the 1920s and 1930s by T. Katayama was explained in the book written by Didier Moreu, GRET 1987, quoted in Rafaralahy, 1999) B. Water management Rice is not an aquatic plant, and its root development under flooded conditions is inhibited and ultimately reduced. Most of the rice roots growing in flooded soil degenerate by the time of panicle initiation (30 days prior to flowering, Kar et al. 1974). Rice fields are traditionally maintained continuously flooded, while with SRI, farmers avoid continuously saturating soil during the vegetative growth period. Table 1 presents the main differences between SRI and the usual system of rice cultivation. Table 1: Differences between SRI and Common Traditional Practices in Rice Cultivation
C. Soil/Nutrient and Pest Management In addition, SRI involves a set of improved practices for better soil, nutrient and pest management that are developed by farmers on a case-by-case basis. Most of the ideas and techniques are based on the principles and techniques of ecological soil and pest management. Results and Experience of SRI Evaluation SRI evaluation under rainfed conditions Rainfed rice cropping makes up around 80-85% of the total rice area cultivated in Cambodia. In the wet season of 2000, 28 farmers experimented with the principles and techniques of SRI within four provinces of Cambodia. The total area under SRI was 1.57 ha. Their average yield was 5 tons per ha, which is 150 % higher than with traditional practices. The most important advances were made by two farmer brothers in Kampong Thom who harvested more than 7 tons per ha, and by one farmer in Prey Veng who was able to harvest more than 10 tons per ha (11.8 to 13. 7 tons per ha). Even though the plots of the latter were small (11 and 8 m²), this showed that a traditional variety could have very high yield potential when grown within SRI principles. In 2001, about 500 farmers adapted SRI in Cambodia. These farmers were supported by CEDAC, PRASAC (the programme for the agricultural sector in Cambodia, supported by European Commission ) and GTZ. According to the data collected from 393 farmers in 6 provinces of Cambodia, the yield under SRI varies considerably, mainly depending on how many elements of SRI are adapted by farmers (see Table 2). Even in the same village, there is one farmer who harvested just 2 tons per ha while another farmer received 10 tons per ha. This implies that SRI is not a fixed technology, but rather a set of principles that farmers can adapt to their own specific needs, preferences and circumstances. It should be noted that the yield obtained from SRI adaptation is dependent on farmer skills and knowledge in managing their plants, water, soil and nutrients. Table 2: Number of Farmers and Yield Harvested under SRI in the Wet Season 2001
The majority of farmers harvested 3 tons per ha or more while rice yields under traditional practice vary between 1 and 2 tons per ha. The most interesting result occurred when 57 farmers harvested more than 5 tons per ha, and among these, 3 farmers harvested more than 10 tons per ha. The yield record for 2001 was 14 tons per ha, achieved by a single woman-farmer in the Kampong Thom provinc. Varieties There were 70 rice varieties used by farmers (the majority were traditional). Data from Table 3 illustrates that with SRI, a higher yield is possible with any variety. However, improved local varieties do better than both traditional and international rice (IR) varieties. This implies that the improvement of seed selection of traditional varieties, which is one of the important elements of SRI, is crucial for maximizing productivity. With SRI, farmers need only a small quantity of seed, allowing them to manage their own seed selection based on the most effective improved traditional variety. Table 3: Yield Variation according to Variety
SRI in flood recession In 2001 CEDAC worked with 6 farmers from the Prek Lovea village in the Kandal Province to test SRI under flood recession conditions in the dry season. The average yield achieved under SRI was 6 tons per ha, which is about 50 % higher than with traditional practices. In 2002, around 40 farmers evaluated SRI under these conditions. Preliminary data indicates that these farmers harvested yields ranging between 5 to 10 tons per ha. Most farmers are using international rice varieties, but in 2002 at least 3 farmers evaluated SRI with a local variety. The first result obtained from one farmer showed that with SRI, the traditional variety could produce 7 tons per ha. This will be a big advantage for farmers with IR varieties. Other SRI advantages observed by flood-recession rice farmers:
Sustainable intensification SRI opens the way for a sustainable system of intensification and diversification of rice-based farming systems in the rainfed lowlands. Cambodian farmers who have adapted SRI have considered it to be a good solution because they gain higher yields with less expenditure on inputs and seeds. The enthusiasm for SRI is very strong in all villages, and it is expected that around 2,000 farmers will adapt SRI in the 2002 wet season. (Note that the conventional term “adopt” is avoided because farmers are expected to be making adaptations in the basic SRI system to fit their own conditions.) Diversification Many rice farmers consider SRI to be an important means for diversifying their rice-based farming systems. As soon as they can harvest higher rice yields from their small plot, farmers can covert some of their rice fields to grow upland crops or dig a pond and canal to produce fish. In partnership with farmers, CEDAC is developing SRI into a System of Intensification and Diversification of production in the rice field, or SID. Currently 180 farmers have started to develop this system. As farmers realize that there is a high return from investing in rice farming, they are more likely to invest in an increase of biomass applied to the soil. This is achieved by doubling efforts to collect organic matter, growing green manure crops in the rice field, and growing trees for producing green leaves to add as mulch or compost. When SRI is achieved with a local variety, there is an abundance of rice stubble after harvest. This stubble if used for mulching the rice field and allows farmers to practice minimal tillage or zero tillage. During the coming wet season, at least 10 farmers will be testing this practice as part of SRI. Conclusion and Future Perspectives SRI shows that there is huge biological potential in the rice plant that remains to be tapped. This potential can be effectively exploited if knowledge to improve plant, water, soil, nutrient and pest management is shared with farmers. Better management captures synergies between root and tiller growth, which in turn lead to greater grain filling. Farmers see SRI as not just a way to maximize rice yield, but also as a way to diversify their rice-based farming systems in the rainfed lowlands. This is essential for the improvement of nutrition, income, and landscape diversity. CEDAC are convinced that SRI is a good solution for millions of Cambodian farmers. Thus, they are reinforcing their efforts to develop and diffuse SRI and SID in Cambodia. Collaboration with other organisations is needed so that as many farmers as possible have an opportunity to learn about SRI. CEDAC are making efforts to ensure that by 2010, all rice farmers in the lowlands of Cambodia will have had the opportunity to learn about SRI. Source: Yang Saing Koma, CEDAC Field Document, April 2002 CEDAC address: Street 223, House No 1, Psar Depot I, Phnom Penh Fax/Phone: 855 23 880 916/23 880 916 Email: Cedac@camnet.com.kh Notes: 1. CEDAC - Center for Cambodian Agricultural Development Studies: a Cambodian non-profit, non-governmental organization. The Center was formed in August 1997 by a group of Cambodian agriculturists with initial support from GRET and Oxfam. 2. SRI principles were first developed in Madagascar - see LEISA newsletter for a full description. << country/story review |
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