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14 Does SRI Work? The first reality check of a low-input rice-growing system took place two years ago and more successes have been documented since. Dr. Mae-Wan Ho reports The clearest sign that SRI works, if not miracles, then certainly well enough, is the number of participants drawn to the first in-depth international assessment of it. Nearly a hundred people from 18 countries were listed as participants in the 192-page proceedings of the 4- day conference, which took place in Sanya, China, in April 2002. More than three-quarters were scientists, with policy-makers, representatives of non-government organisations, international organisations, private companies and farmers making up the rest. Participants from the host country China made up more than half of the total, and all were scientists from prestigious rice research institutes, agriculture academies or universities. The conference was convened, not to assess whether SRI works - for that was the experience of almost everyone who presented papers at the conference - but to assess across nations, "the opportunities and limitations" of a practice that "can give yields about twice the present world average without reliance on new varieties or agrochemicals." The conference did bring together a substantial body of evidence from around the world that SRI can increase yield in a variety of soils, climatic conditions, with various local adaptations, and using both indigenous and commercial 'high yielding' rice varieties. SRI has been "practice-led" thus far, but participants at the conference felt it was time for scientists to catch up and research the knowledge-base, so that a healthy dialectical relationship between practice and knowledge can be achieved to help advance this important project of delivering food security and health to more than half the world's population. Since then, more successes have been reported, leaving the scientific establishment even further behind (see "Fantastic rice yields fact or fallacy?" this series). Super-yields in Madagascar The province of Fianarantsoa, situated in the south-central highlands of SCIENCE IN SOCIETY 23, AUTUMN 2004
15 Above: Professor Yuan Longping and Dr. Monty Jones two rice breeders are joint recipients of 2004 World Food Prize Left: sparser spacing and Right; profusion of roots, both courtesy of Dr. Zhu Defeng, China National Rice Research Institute, Zhejiang. Madagascar, now lays claim to the highest yielding rice-fields in the world since the introduction of SRI in the 1990s. The highlands are subtropical, with annual rainfall averaging 1375mm. The rainy season occurs during the hot months in the year, where the average temperature rises above 20C. The Fianarantsoa region is often affected by cyclones during the rainy season. Fianarantsoa attained rice yields of more than 8 t/ha in the first year of applying SRI methods, up from the 2 t/ha national average. SRI in this region is increasingly linked with the use of compost in rotational cropping with potatoes, beans or other vegetables in the off-season. In the second and succeeding years, the residual and cumulative effects of soil organic matter from composting increased yields still further, to 16 t/ha. By the sixth year, yields as high as 20 t/ha were measured on farmers' fields in Tsaramandroso, Talatamaty and Soatanana. Bruno Andrianaivo, senior agronomist of FOFIFA (National Centre for Applied Research on Rurual Development in Madagascar) emphasized that such high yields cannot be achieved immediately, but requires the cumulative effects of 6 years under SRI. However, simply on the conservative figure of 8 t/ha yield from SRI practice Andrianaivo estimated a net return to the farmer of 5 million Fmg (about US$770), compared with around 250 000 Fmg (less than US$40) for conventional practice. Acceptance in China Professor Yuan Longping of China National Hybrid Rice Research and Development Centre played a key role in creating high-yielding superhybrids throughout the late 1990s and early 2000s by conventional breeding methods. This distinguished researcher, now in his 70s, has a long string of national and international awards behind him, and is joint recipient of this year's World Food Prize. Yuan's Centre had already broken all records in boosting rice-hybrid yields when he first heard about SRI from a paper written by Norman Uphoff of Cornell International Institute for Food, Agriculture and Development (see "Fantastic rice yields fact or fallacy?" this series). Yuan conducted the first trial of SRI in his Centre's station in Sanya from winter 2000 to spring 2001. Only three varieties yielded above 10 t/ha, and SRI gave an average increase of around 10% over the conventional practice. The following year, tests were conducted in the summer at the Centre's station in Changsha. Two varieties yielded 12 t/ha, and one 12.9 t/ha, a record for the Centre so far. This encouraged more Chinese scientists to conduct SRI research. Of the 8 locations in which his Centre was involved, 5 locations got good results, with yields over 12 t/ha. Since then, trials by a private sector company, the Meishan Seed Company in Sichuan Province, using a modified SRI method, achieved yields of 15.67 t/ha and 16 t/ha in two different plots, both new records in Sichuan Province (yield in the conventional field was 11.8 t/ha). Yuan's preliminary evaluation of SRI is enthusiastic: "SRI is a promising way to increase rice yield and to realize the yield potential of any variety…whether high-yielding variety (HYV) or local variety." He confirmed that the method can promote more vigorous growth of rice plants, especially tillers and roots, and noted in addition, less insect and disease problems during the vegetative growth stage, and that there are definite varietal differences in response to SRI practices: those with strong tillering ability and 'good plant type' are more favourable for SRI cultivation. "SRI gives higher output with less input, but requires very laborious manual work which makes it more suitable for small farms in developing countries" he said. Moreover, SRI should be modified and adapted to suit local conditions, and as experience teaches. For China, he recommended a long list of modifications, including using tray nurseries to raise the young seedlings instead of flooded seedbeds, so as to reduce the trauma of transplanting; and controlling tillerformation, for although increased tillering gives many more rice-forming panicles, the percentage of productive tillers falls off with the number of tillers, so there is an optimum maximum number. He definitely thinks there is scope for combining genetic improvement with SRI methods. For example, breeding plants with a strong ability to form tillers would be appropriate for improving the response to SRI. Detailed analyses of the trials were presented in several multiauthor research papers. For example, the economic benefits of applying SRI methods were estimated for the www.i-sis.org.uk
Page 1 and 2: Science in Society ISSUE 23 Autumn
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Page 7 and 8: 7 Figure 1. Maize yields in 5 sites
Page 9 and 10: Rice Wars 9 Fantastic Rice Yields F
Page 12 and 13: 12 New Rice for Africa Dr. Mae-Wan
Page 16 and 17: 16 hybrid rice Liangyoupei 9, which
Page 18 and 19: ier around the field. There is a pa
Page 20 and 21: 20 Chinese researchers have develop
Page 22 and 23: 22 Two Rice Better than One Lim Li
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Page 36 and 37: 36 denum of cattle. The studies wer
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Page 40 and 41: 40 Technology Watch Bio-remediation
Page 42 and 43: Rethinking health Selenium Conquers
Page 44 and 45: 44 Delivering Good Health Through G
Page 46 and 47: 46 process in which new humans are
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Page 50 and 51: 50 Water Forms Massive Exclusion Zo

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