0301 Understanding an Opportunity to Raise Rice Sector Productivity

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Presented by: Norman Uphoff

Presented at: National SRI Workshop, CNRRI, Hangzhou

March 2003

Published in: Technology, Education
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  • Prepared with information available as of February 1, 2003. These slides can be used or adapted, even translated, however SRI colleagues would be useful for explaining this methodology to others.
  • Picture provided by Gamini Batuwitage, Sri Lanka, of field that yielded 17 t/ha in 2000.
  • Prepared with information available as of February 1, 2003. These slides can be used or adapted, even translated, however SRI colleagues would be useful for explaining this methodology to others.
  • This figure is from research from the China National Rice Research Institute reported at the Sanya conference in April 2002 and published in the Proceedings. Two different rice varieties were used with SRI and conventional (CK) methods. The second responded more positively to the methods in terms of leaf area and dry matter as measured at different elevations, but there was a very obvious difference in the phenotypes produced from the first variety's genome by changing cultivation methods from conventional to SRI.
  • Summary results from two sets of factorial trials in two different agroecological settings in 2000 and 2001 by honors students in the Faculty of Agriculture at the University of Antananarivo. The first setting was on the west coast of Madagascar, at an agricultural experiment center near Morondava, with a tropical climate, near sea level, and poor sandy soil. (This location was chosen because there are few pest or disease problems during that season which could affect plant performance.) The second was on the high plateau near the village of Anjomakely, 18 km south of Antananarivo, with a temperate climate, about 1200 m elevation, and better soils, comparing results on better clay soil and poorer loam soil. In 2000, Jean de Dieu Rajonarison did trials on 288 plots (2.5x2.5 m) at the Centre de Baobab, with sandy soil [ sable roux], evaluating the effects of five factors: variety – HYV [2798] vs. traditional [riz rouge]; age of seedling [16-day vs. 8-day], seedlings per hill [3 vs. 1], water management [continuous flooding vs. water control, with deliberate aeration of the soil during the vegetative growth period], and nutrient amendments [none vs. NPK vs. compost]. The study was designed with spacing as a sixth factor [25x25 vs. 30x30cm], sok that there were 96 combinations (2x2x2x3x2x2), with three replications. But both spacings were within the SRI range, and the average yield distinguished by spacing [each N = 144] was identical, 3.18 t/ha. So the analysis deals with only five factors, having six replications for each average reported. Plots were randomly distributed according to a modified Fisher bloc design, except for water management, for which the plot with these two different treatments had to be separate to avoid effects of lateral seepage. In 2000, Andry Andriankaja did trials on 240 plots (2.5x2.5m) on a farmer’s fields near Anjomakely, using a traditional rice variety [ riz rouge], evaluating the effects of five factors: soil [clay vs. loam], age of seedling [20-day vs. 8-day – with colder temperatures, the onset of the 4 th phyllochron of growth is later than at Morondava], seedlings per hill [3 vs. 1], water management [continuous flooding vs. water control, with deliberate aeration of the soil during the vegetative growth period], and nutrient amendments [none vs. NPK vs. compost]. The reason why there are only 240 trials rather than 288 is that trials with no amendments were done only on the clay soil plots, not on the poorer loam soil plots, which were known to have low inherent fertility. This made for 40 combinations, with six replications. [The spacing factor as in the Morondava trials was not significant, with a difference of only 80 kg/ha for the two sets, each N = 120.] Again, all yields reported are averages for 6 replicated plots randomly distributed.
  • Summary results from two sets of factorial trials in two different agroecological settings in 2000 and 2001 by honors students in the Faculty of Agriculture at the University of Antananarivo. The first setting was on the west coast of Madagascar, at an agricultural experiment center near Morondava, with a tropical climate, near sea level, and poor sandy soil. (This location was chosen because there are few pest or disease problems during that season which could affect plant performance.) The second was on the high plateau near the village of Anjomakely, 18 km south of Antananarivo, with a temperate climate, about 1200 m elevation, and better soils, comparing results on better clay soil and poorer loam soil. In 2000, Jean de Dieu Rajonarison did trials on 288 plots (2.5x2.5 m) at the Centre de Baobab, with sandy soil [ sable roux], evaluating the effects of five factors: variety – HYV [2798] vs. traditional [riz rouge]; age of seedling [16-day vs. 8-day], seedlings per hill [3 vs. 1], water management [continuous flooding vs. water control, with deliberate aeration of the soil during the vegetative growth period], and nutrient amendments [none vs. NPK vs. compost]. The study was designed with spacing as a sixth factor [25x25 vs. 30x30cm], sok that there were 96 combinations (2x2x2x3x2x2), with three replications. But both spacings were within the SRI range, and the average yield distinguished by spacing [each N = 144] was identical, 3.18 t/ha. So the analysis deals with only five factors, having six replications for each average reported. Plots were randomly distributed according to a modified Fisher bloc design, except for water management, for which the plot with these two different treatments had to be separate to avoid effects of lateral seepage. In 2000, Andry Andriankaja did trials on 240 plots (2.5x2.5m) on a farmer’s fields near Anjomakely, using a traditional rice variety [ riz rouge], evaluating the effects of five factors: soil [clay vs. loam], age of seedling [20-day vs. 8-day – with colder temperatures, the onset of the 4 th phyllochron of growth is later than at Morondava], seedlings per hill [3 vs. 1], water management [continuous flooding vs. water control, with deliberate aeration of the soil during the vegetative growth period], and nutrient amendments [none vs. NPK vs. compost]. The reason why there are only 240 trials rather than 288 is that trials with no amendments were done only on the clay soil plots, not on the poorer loam soil plots, which were known to have low inherent fertility. This made for 40 combinations, with six replications. [The spacing factor as in the Morondava trials was not significant, with a difference of only 80 kg/ha for the two sets, each N = 120.] Again, all yields reported are averages for 6 replicated plots randomly distributed.
  • The "economist's $100 bill" refers to the joke about an economist and his friend who were walking together down the street one day when the friend saw a $100 bill on the sidewalk. Thinking that his friend, being concerned with money, would surely pick the bill up, he did not reach down himself. But the economist walked right by. The friend asked, didn't you see that $100 bill on the sidewalk? Why didn't you pick it up? The economist replied,It wasn't a real $100 bill. If it had been genuine, since people are rational, someone would have picked it up by now, so I am sure that it was a counterfeit, and I didn't want to waste any effort on it. Agronomists have regarded SRI with similar skepticism, dismissing it by saying if it were indeed as good as reported, it should have been discovered previously, given the many millions of farmers and thousands of scientists who have worked with rice. So, therefore, SRI must not be genuine. SRI contradicts a number of key concepts held by agronomists and economists, giving them reasons to reject it, without giving it an empirical evaluation. However, the evidence in support of SRI is mounting year by year, month by month.
  • These data from a study done by Fide Raobelison under the supervision of Prof. Robert Randriamiharisoa at Beforona station in Madagascar, and reported in Prof. Robert's paper in the Sanya conference proceedings, give the first direct evidence to support our thinking about the contribution of soil microbes to the super-yields achieved with SRI methods. The bacterium Azospirillum was studied as an "indicator species" presumably reflecting overall levels of microbial populations and activity in and around the plant roots. Somewhat surprisingly, there was no significant difference in Azospirillum populations in the rhizosphere. But there were huge differences in the counts of Azospirillum in the roots themselves according to soil types (clay vs. loam) and cultivation practices (traditional vs. SRI) and nutrient amendments (none vs. NPK vs. compost). NPK amendments with SRI produce very good results, a yield on clay soil five times higher than traditional methods with no amendments. But compost used with SRI gives a six times higher yield. The NPK increases Azospirillum (and other) populations, but most/much of the N that produced a 9 t/ha yield is coming from inorganic sources compared to the higher 10.5 t/ha yield with compost that depends entirely on organic N. On poorer soil, SRI methods do not have much effect, but when enriched with compost, even this poor soil can give a huge increase in production, attributable to the largest of the increases in microbial activity in the roots. At least, this is how we interpret these findings. Similar research should be repeated many times, with different soils, varieties and climates. We consider these findings significant because they mirror results we have seen in other carefully measured SRI results such as the Anjomakely factorial trials (Slide 24) and the previous season's trials with SRI at Beforona (10.2 t/ha).
  • This picture was contributed from Cambodia by Koma Yang Saing (CEDAC). Viewers should try to imagine the very small single young seedling from which this massive plant grew.
  • This is a figure also from research reported by the China National Rice Research Institute to the Sanya conference and published in its proceedings. It shows how the roots of the same variety (two varieties shown) grow deeper into the soil with SRI methods compared to conventional ones (CK).
  • This figure from report by Nanjing Agricultural University researchers to the Sanya conference, and reproduced from those proceedings, shows that the oxygenation ability of rice roots growing under SRI conditions are about double the ability, throughout the growth cycle, compared to the same variety grown under conventional conditions.
  • Here we look just at the effect of young seedlings, on better and poorer soil, at Anjomakely. The synergistic effect of compost with aerated soil is seen in the bottom three lines. Compost with saturated soil does less well (7.7 t/ha) than NPK with aerated soil (8.77 t/ha), but compost with aerated soil does by far the best (10.35 t/ha) on better soil. The same relationship is seen on poorer soil (right-hand column).
  • This picture from Sri Lanka shows two fields having the same soil, climate and irrigation access, during a drought period. On the left, the rice grown with conventional practices, with continuous flooding from the time of transplanting, has a shallower root system that cannot withstand water stress. On the right, SRI rice receiving less water during its growth has deeper rooting, and thus it can continue to thrive during the drought. Farmers in Sri Lanka are coming to accept SRI in part because it reduces their risk of crop failure during drought.
  • This helps to explain our problem of "the agronomists' $100 bill." SRI is quite "counterintuitive." Indeed, it even sounds crazy. But we have experience and evidence that this "less is more" dynamic operates, and subsequent slides provide a number of scientific explanations for why fewer or smaller inpouts produce more in the case of irrigated rice
  • This helps to explain our problem of "the agronomists' $100 bill." SRI is quite "counterintuitive." Indeed, it even sounds crazy. But we have experience and evidence that this "less is more" dynamic operates, and subsequent slides provide a number of scientific explanations for why fewer or smaller inpouts produce more in the case of irrigated rice
  • This helps to explain our problem of "the agronomists' $100 bill." SRI is quite "counterintuitive." Indeed, it even sounds crazy. But we have experience and evidence that this "less is more" dynamic operates, and subsequent slides provide a number of scientific explanations for why fewer or smaller inpouts produce more in the case of irrigated rice
  • This was one of the first data sets that began laying a scientific foundation for SRI. Data were gathered from 76 farmers around Ambatovaky, a town on the western side of the peripheral zone around Ranomafana National Park in Madagascar, during the 1996-97 season. We had confidence in the field worker who collected the data, Simon Pierre, who had worked with Fr. de Laulanie before his death. The correlation between number of tillers per plant and number of grains per panicle was +.65, rather than the negative one expected from the literature. We have seen this positive relationship many times since this first analysis was done.
  • Dr. Janaiah visited Sri Lanka the last week of October, 2002, and talked with 30 farmers in four villages who had been practicing SRI and who could give him detailed data. He had previously done such an evaluation for IRRI of the costs and benefits of adopting hybrid rice, having been on the IRRI staff in Los Banos from 1999 to 2002. He found SRI to be a much more profitable innovation for rice production than adoption of hybrids. We have found that SRI methods give the highest yields with hybrid varieties so there is not necessary contradiction or competition between the two. The SRI results reported from the Philippines, by the Agricultural Training Institute of the Department of Agriculture, from trials with three varieties at its Cotobato center in Mindanao (slide 20), calculated that the cost of production per hectare was 25,000 pesos, while the value of the rice yield with SRI was 96,000 pesos, a return of almost four times. Thus there are other evaluations of net profit from SRI that are even more favorable than Janaiah's calculation.
  • Dr. Janaiah visited Sri Lanka the last week of October, 2002, and talked with 30 farmers in four villages who had been practicing SRI and who could give him detailed data. He had previously done such an evaluation for IRRI of the costs and benefits of adopting hybrid rice, having been on the IRRI staff in Los Banos from 1999 to 2002. He found SRI to be a much more profitable innovation for rice production than adoption of hybrids. We have found that SRI methods give the highest yields with hybrid varieties so there is not necessary contradiction or competition between the two. The SRI results reported from the Philippines, by the Agricultural Training Institute of the Department of Agriculture, from trials with three varieties at its Cotobato center in Mindanao (slide 20), calculated that the cost of production per hectare was 25,000 pesos, while the value of the rice yield with SRI was 96,000 pesos, a return of almost four times. Thus there are other evaluations of net profit from SRI that are even more favorable than Janaiah's calculation.
  • The "economist's $100 bill" refers to the joke about an economist and his friend who were walking together down the street one day when the friend saw a $100 bill on the sidewalk. Thinking that his friend, being concerned with money, would surely pick the bill up, he did not reach down himself. But the economist walked right by. The friend asked, didn't you see that $100 bill on the sidewalk? Why didn't you pick it up? The economist replied,It wasn't a real $100 bill. If it had been genuine, since people are rational, someone would have picked it up by now, so I am sure that it was a counterfeit, and I didn't want to waste any effort on it. Agronomists have regarded SRI with similar skepticism, dismissing it by saying if it were indeed as good as reported, it should have been discovered previously, given the many millions of farmers and thousands of scientists who have worked with rice. So, therefore, SRI must not be genuine. SRI contradicts a number of key concepts held by agronomists and economists, giving them reasons to reject it, without giving it an empirical evaluation. However, the evidence in support of SRI is mounting year by year, month by month.
  • This picture was provided by Koma Yang Saing (CEDAC) of a pleased Cambodian farmer, showing the size of a massive root ball with a SRI rice plant.
  • These are just the most obvious contributions. Our understanding of this netherworld is limited, though fortunately there are a growing number of microbiologists using very advanced modern techniques, such as DNA analysis, to map and track what is going on in the soil. The discussion that follows is can be viewed as introductory or superficial, or both.
  • Most people know that leguminous plants "fix" N in their roots through nodules on the roots inhabited by certain bacteria, rhizobia. And by implication, most thinks that non-leguminous plants "do not fix nitrogen." This is correct in terms of locus, but it misleads. All of the gramineae species (rice, wheat, sugar cane, etc.) have free-living bacteria in their root zones (referred to as 'associated' microbes) that fix N. Even in fertilized crops, a majority of the N taken up by the roots is from organic sources. And there is evidence that adding inorganic N to the root zone inhibits or suppresses the roots' and microbes' production of nitrogenase, the enzyme needed to fix N. So there is a tradeoff, in that adding inorganic N fertilizer reduces the N that is produced by natural biological processes. Or most relevance to SRI is research published more than 30 years ago reporting that when aerobic and anaerobic horizons of soil are mixed, BNF increases greatly compared to that originating from either aerobic or anaerobic soil. This suggests that the water management and weeding practices of SRI could be actively promoting N production in the soil. We have no research results to support this inference (though see data in Slide 49), but the yield increases with SRI practices require large amounts of N. BNF is the most plausible explanation.
  • Here we look just at the effect of young seedlings, on better and poorer soil, at Anjomakely. The synergistic effect of compost with aerated soil is seen in the bottom three lines. Compost with saturated soil does less well (7.7 t/ha) than NPK with aerated soil (8.77 t/ha), but compost with aerated soil does by far the best (10.35 t/ha) on better soil. The same relationship is seen on poorer soil (right-hand column).
  • Summary results from two sets of factorial trials in two different agroecological settings in 2000 and 2001 by honors students in the Faculty of Agriculture at the University of Antananarivo. The first setting was on the west coast of Madagascar, at an agricultural experiment center near Morondava, with a tropical climate, near sea level, and poor sandy soil. (This location was chosen because there are few pest or disease problems during that season which could affect plant performance.) The second was on the high plateau near the village of Anjomakely, 18 km south of Antananarivo, with a temperate climate, about 1200 m elevation, and better soils, comparing results on better clay soil and poorer loam soil. In 2000, Jean de Dieu Rajonarison did trials on 288 plots (2.5x2.5 m) at the Centre de Baobab, with sandy soil [ sable roux], evaluating the effects of five factors: variety – HYV [2798] vs. traditional [riz rouge]; age of seedling [16-day vs. 8-day], seedlings per hill [3 vs. 1], water management [continuous flooding vs. water control, with deliberate aeration of the soil during the vegetative growth period], and nutrient amendments [none vs. NPK vs. compost]. The study was designed with spacing as a sixth factor [25x25 vs. 30x30cm], sok that there were 96 combinations (2x2x2x3x2x2), with three replications. But both spacings were within the SRI range, and the average yield distinguished by spacing [each N = 144] was identical, 3.18 t/ha. So the analysis deals with only five factors, having six replications for each average reported. Plots were randomly distributed according to a modified Fisher bloc design, except for water management, for which the plot with these two different treatments had to be separate to avoid effects of lateral seepage. In 2000, Andry Andriankaja did trials on 240 plots (2.5x2.5m) on a farmer’s fields near Anjomakely, using a traditional rice variety [ riz rouge], evaluating the effects of five factors: soil [clay vs. loam], age of seedling [20-day vs. 8-day – with colder temperatures, the onset of the 4 th phyllochron of growth is later than at Morondava], seedlings per hill [3 vs. 1], water management [continuous flooding vs. water control, with deliberate aeration of the soil during the vegetative growth period], and nutrient amendments [none vs. NPK vs. compost]. The reason why there are only 240 trials rather than 288 is that trials with no amendments were done only on the clay soil plots, not on the poorer loam soil plots, which were known to have low inherent fertility. This made for 40 combinations, with six replications. [The spacing factor as in the Morondava trials was not significant, with a difference of only 80 kg/ha for the two sets, each N = 120.] Again, all yields reported are averages for 6 replicated plots randomly distributed.
  • This is a SRI rice nursery in Sri Lanka, showing one way (but only one of many ways) to grow young seedlings. The soil in this raised bed was a mixture of one-third soil, one-third compost, and one-third chicken manure. (The flooding around it is because the surrounding field is being readied for transplanting; normally there would not be so much water standing around the nursery.)
  • Here the seedlings are being removed. We would recommend that they be lifted with a trowel, to have minimum disturbance of the roots, but these seedlings are so vigorous that this manual method is successful. This farmer has found that his seedlings, when transplanted with two leaves at time of transplanting, already put out a third leave the next day after transplanting, indicating that there was no transplant 'shock.'
  • Here the field is being 'marked' for transplanting with a simple wooden 'rake.' If the soil is too wet, these lines will not remain long enough for transplanting. There are drains within the field to carry excess water away from the root zone.
  • Here are seedlings being removed from a clump for transplanting. Note that the yellow color comes from the sunlight reflecting off the plant. The plant's color is a rich green, indicating no N deficiency.
  • Here the seedlings are being set into the soil, very shallow (only 1-2 cm deep). The transplanted seedlings are barely visible at the intersections of the lines. This operation proceeds very quickly once the transplanters have gained some skill and confidence in the method. As noted already, these seedling set out with two leaves can already have a third leaf by the next day.
  • The SRI field looks rather sparse and unproductive at first. Up to the 5th or 6th week, SRI fields look rather miserable, and farmers can wonder why they ever tried this method and 'wasted' their precious land with such a crazy scheme. But the SRI plot here will yield twice as much rice as the surrounding ones once the rapid tillering (and root growth) begins between 35 and 45 days.
  • This is one of many happy Sri Lankan farmers with his SRI field nearing harvest time. Some young farmers have taken up growing "eco-rice," i.e., traditional varieties grown organically to be sold for a much higher price than conventional HYV rice, because of better texture, taste, smell and aroma and more assurance of healthy food. SRI in this way is starting to contribute to the preservation of rice biodiversity. As noted above, SRI methods work well with hybrid varieties and HYVs. These give the highest yields with SRI methods. But as SRI methods can double or triple traditional-variety yields, these old varieties become economically more advantageous with SRI. Much more remains to be learned about and from SRI. But we have now enough accumulated evidence, based on experience in farmers' fields, not just on experiment stations, and consistent with what is known in the literature (though often not previously connected up to promote increased rice productivity), to have confidence that this methodology will contribute to greater food security and a better environment. SRI, developed by Fr. de Laulanie and promoted by his friends in Association Tefy Saina, and by a growing number of colleagues in many countries around the world, could help to improve other crop production. The world does not need a doubling of rice production, but it does need increased productivity in the rice sector, as this is the largest single agricultural sector in the world in terms of the resources devoted to it. By raising the productivity of land, labor, water and capital in the rice sector, we should be able to meet our staple food needs with less of these resources, which have significant opportunity costs. We hope that SRI methods will enable farmers to redeploy some of their land, labor, water and capital to producing other, higher-value and more nutritious crops, thereby enhancing the well-being of rural households and urban populations. The urban poor should benefit from lower prices for rice that will follow from higher productivity. SRI is not a labor-intensive method that will 'keep rice production backward,' as was alleged by its critics in Madagascar for many years, but a strategy for achieving diversification and modernization in the agricultural sector.
  • 0301 Understanding an Opportunity to Raise Rice Sector Productivity

    1. 1. The System of Rice Intensification (SRI): Understanding an Opportunity to Raise Rice Sector Productivity Norman Uphoff, CIIFAD Cornell University, USA
    2. 2. For Centuries, Even Millennia, We Have Been ABUSING and MISTREATING the Rice Plant <ul><li>We have FLOODED it – drowning its roots </li></ul><ul><li>We have CROWDED it – inhibiting the growth potential of its canopy and roots </li></ul><ul><li>Now we apply FERTILIZERS and chemical BIOCIDES – that suppress or kill soil biota which provide many services to the plants </li></ul><ul><li>Bacteria, fungi, etc. provide N fixation, P solubilization, disease protection, etc. </li></ul>
    3. 3. The System of Rice Intensification <ul><li>Evolved in Madagascar over 20-yr period by Fr. Henri de Laulanié, S.J. – through working with farmers, observing, doing experiments, also having some luck </li></ul><ul><li>SRI synthesized 20 years ago (1983-84) – now spreading around the world </li></ul><ul><li>SRI is a set of principles and insights translated into certain practices that change the growing environment of rice to get healthier, more productive plants </li></ul><ul><li>These principles were developed in China as the ‘3S system’ – same ideas/concepts </li></ul>
    4. 4. Canopy of an individual rice plant grown under SRI conditions; this variety (Swarna) is normally ‘shy-tillering’ Andhra Pradesh, India, Rabi season, 2003-04
    5. 5. Roots of a single rice plant (MTU 1071) grown at Agricultural Research Station Maruteru, AP, India, Kharif 2003
    6. 6. SRI field in Sri Lanka -- yield of 13 t/ha with panicles having 400+ grains
    7. 7. CFA Camilo Cienfuegos, Cuba 14 t/ha -- Variety Los Palacios 9
    8. 8. SRI (3S) in Summary : A set of principles/methods to get more productive PHENOTYPES from any existing GENOTYPE of rice. SRI (3S) changes the management of plants, soil, water, and nutrients to (a) induce greater ROOT growth and (b) nurture more abundant and diverse populations of SOIL BIOTA
    9. 9. Plant Physical Structure and Light Intensity Distribution at Heading Stage (CNRRI Research --Tao et al. 2002)
    10. 10. Dry Matter Accumulation between SRI and Control (CK) Practices (kg/ha) at Full Heading (Zheng et al., SAAS, 2003)
    11. 11. Dry Matter Accumulation between SRI and Control (CK) Practices (kg/ha) at Maturity (Zheng et al., SAAS, 2003)
    12. 12. Table 2. Different sizes of the leaf blade (cm) (Zheng et al., SAAS, 2003) 11.98 15.95 7.96 18.49 19.11 14.97 9.79 14.59 % 0.20 8.86 0.16 9.00 0.30 9.29 0.14 8.18 +/- 1.67 55.56 2.01 48.67 1.57 62.03 1.43 56.07 CK 1.87 64.41 2.17 57.67 1.87 71.32 1.57 64.25 SRI Width Length Width Length Width Length Width Length Average Flag leaf 2 nd leaf 3 rd leaf Item
    13. 13. Figure 1. Change of leaf area index (LAI) during growth cycle (Zheng et al., 2003)
    14. 14. Different P aradigms of Production <ul><li>The GREEN REVOLUTION paradigm: </li></ul><ul><li>(a) Change the genetic potential of plants, and </li></ul><ul><li>(b) Increase the use of external inputs -- more water, fertilizer, insecticides, etc. </li></ul><ul><li>SRI changes certain management practices for plants, soil, water and nutrients so that: </li></ul><ul><li>(a) Root growth is promoted , and </li></ul><ul><li>(b) Abundance & diversity of soil microbial populations -- also soil fauna – are increased </li></ul><ul><li>Reduce WATER and COSTS OF PRODUCTION </li></ul>
    15. 15. Greatest Benefit Is not YIELD <ul><li>Yield varies , often widely -- besides, for farmers, profitability is more important </li></ul><ul><li>From society’s perspective, what is most important is factor productivity – kg per land, labor, capital, and water ! </li></ul><ul><li>Rather than focusing on yield, I want to consider possible explanations for SRI results – try to advance science for rice </li></ul><ul><li>Some of what I say will have evidence & support -- otherwise strong hypotheses </li></ul>
    16. 16. SRI Practices Should Always be Varied to Suit Conditions <ul><li>Four basic elements of SRI practice: </li></ul><ul><li>Young seedlings are used -- DS an option </li></ul><ul><li>Wide spacing – single plants, square pattern </li></ul><ul><li>Soil aeration – thru water management and weeding, so aerobic conditions prevail in soil </li></ul><ul><li>Organic matter to be enhanced in the soil – fertilizer not needed if compost is used </li></ul><ul><li>Recommend weed control with ‘rotating hoe’ </li></ul><ul><li>These are the basic ideas for SRI practice </li></ul>
    17. 17. Explanations: 1. Above-Ground Environment <ul><li>Create ‘ the edge effect ’ for the whole field </li></ul><ul><li>Only avoid edge effect for measurement; promote it agronomically (triangle spacing) </li></ul><ul><li>Too close spacing affects photosynthesis within canopy: measurements at AARD (Sukamandi, Indonesia) found that with normal spacing, lower leaves had to be ‘subsidized’ by upper leaves; but wider spacing enables whole plant to contribute </li></ul>
    18. 18. Explanation: 2. Nitrogen Provision <ul><li>Rice yields increased 40-60% when same amount of N provided equally in both NO 3 and NH 4 forms vs. when all N is provided as NH 4 (Kronzucker et al., 1998) </li></ul><ul><li>BNF increases greatly with alternated aerobic/anaerobic conditions (Magdoff and Bouldin, Plant and Soil , 1970) </li></ul><ul><li>Contributions of protozoa to N supply? </li></ul><ul><li>Also contributions from endophytes ? </li></ul>
    19. 20. Explanations: 3. Phosphorus Solubilization <ul><li>This nutrient is often limiting factor </li></ul><ul><li>Large amounts of P in soil (90-95%) are in ‘unavailable’ form </li></ul><ul><li>Alternating wetting and drying of soil increased P in soil solution by 85-1900% compared with soils just wet or just dry (Turner and Haygarth, Nature , May 2001) </li></ul><ul><li>Aerobic bacteria acquire P from ‘unavailable’ sources during dry phase; during wet phase they lyse and release P into the soil solution </li></ul>
    20. 21. Explanations: 4. Mycorrhizal Fungi <ul><li>90+% of terrestrial plants derive benefits from and even depend on mycorrhizal associations (infections) </li></ul><ul><li>Mycorrhizal hyphae (filaments) extend into soil and expand volume accessible to the plant by 10-100x , acquiring water, P and other nutrients , also providing protective/other services </li></ul><ul><li>Flooded rice forgoes these benefits </li></ul>
    21. 22. Explanations: 5. Phytohormones <ul><li>Aerobic bacteria and fungi produce auxins, cytokinins, gibberellins , etc. in the rhizosphere </li></ul><ul><li>Huge literature has documented effects of microbially-produced phytohormones (e.g., Frankenberger and Arshad, 1995) </li></ul><ul><li>Root growth in SRI plants probably are not just due to physiological processes within the plants, but are stimulated by aerobic microorganisms? Roots are key </li></ul>
    22. 23. Single Cambodian rice plant transplanted at 10 days
    23. 24. Cuba -- Variety VN 2084 (Bolito) -- 52 DAP
    24. 25. Dry Matter Distribution of Roots in SRI and Conventionally-Grown Plants at Heading Stage (CNRRI research: Tao et al. 2002) Root dry weight (g)
    25. 26. Table 13: Root Length Density (cm. cm -3 ) under SRI, ‘Modern’ (SRA) and Conventional Practice (from Barison, 2002) Results from replicated on-station trials 0.06 0.13 0.36 1.19 1.28 4.11 Conventional practice 0.07 0.15 0.31 0.55 0.85 3.24 SRA without fertilization 0.09 0.18 0.34 0.65 0.99 3.73 SRA with NPK and urea 0.20 0.25 0.32 0.57 0.71 3.33 SRI -- without compost 0.23 0.30 0.33 0.61 0.75 3.65 SRI -- with compost 40-50 30-40 20-30 10-20 5-10 0-5 Soil layers (cm) Treatments
    26. 27. Figure 8: Linear regression relationship between N uptake and grain yield for SRI and conventional methods, using QUEFTS modeling (from Barison, 2002) Results are from on-farm comparisons (N = 108)
    27. 28. Figure 9: Estimation of balanced N uptake for given a grain yield for rice plants with the SRI and conventional systems, using QUEFTS modeling (same for P and K) (Barison, 2002) Results are from on-farm comparisons (N = 108)
    28. 29. Root Oxygenation Ability with SRI vs. Conventionally-Grown Rice Research done at Nanjing Agricultural University, Wuxianggeng 9 variety (Wang et al. 2002)
    29. 30. What Are Problems for SRI? <ul><li>Labor Requirements – initially more labor-intensive -- 25-50% </li></ul><ul><li>As farmers gain skill & experience, this is reduced, and SRI can even become labor-saving </li></ul><ul><li>GTZ evaluation of SRI in Cambodia: no difference in labor requirements (305 vs. 302 hrs/ha) – better timing </li></ul><ul><li>CEDAC evaluation: 55% say ‘easier’ </li></ul>
    30. 31. Roller-marker devised by Lakshmana Reddy, East Godavari, AP, India, to save time in transplanting operations; his yield in 2003-04 rabi season was 16.2 t/ha paddy (dry weight)
    31. 32. 4-row weeder designed by Gopal Swaminathan, Thanjavur, TN, India
    32. 33. Motorized weeder developed by S. Ariyaratna Sri Lanka
    33. 34. Adjustable-width weeder designed by Hari R., Moramanga, Madagascar (from IRRI design)
    34. 35. Labor-Saving Methods of Crop Establishment <ul><li>Tray methods – being developed in China, also in Cuba </li></ul><ul><li>Sowing/Thinning methods – started in India and Sri Lanka – broadcasting pregerminated seed (25 kg/ha) or young seedlings -- then ‘weed’ as usual , creating wide spacing with a square pattern (sacrifice seed for labor) </li></ul>
    35. 36. Seeder Developed in Cuba
    36. 37. What Are Problems for SRI? <ul><li>2. Water Control – needed to get the best results with SRI methods </li></ul><ul><li>This constraint but can be reduced by investment in physical facilities or in organization and management </li></ul><ul><li>Most rice-growing countries will need to reduce the allocations of water for rice sector in coming yrs </li></ul><ul><li>SRI can help reduce water demand </li></ul>
    37. 38. Emerging Benefits of SRI? <ul><li>1. Resistance to Abiotic Stresses – climate becoming more ‘extreme’ and more unpredictable </li></ul><ul><li>Observed resistance to drought (Sri Lanka, several years) , hurricane (Sichuan – Sept. 2002) , typhoon (AP, India – Dec. 2003) , cold spell (AP, India – February 2004) </li></ul><ul><li>Resistance to lodging due to roots? </li></ul>
    38. 39. Two rice fields in Sri Lanka -- same variety, same irrigation system, and same drought : conventional methods (left), SRI (right)
    39. 40. Emerging Benefits of SRI? <ul><li>2. Resistance to Pests and Diseases – widely reported by farmers – probably reflecting the protective services of soil microorganisms </li></ul><ul><li>3. Higher Milling Outturn by ~ 15%: SRI paddy raises outturn in India from 66 to 75%; and in Cuba, from 60 to 68-71% </li></ul><ul><li>Fewer unfilled grains (less chaff) </li></ul><ul><li>Fewer broken grains (less shattering) </li></ul>
    40. 41. Emerging Benefits of SRI? <ul><li>4. Higher Nutritional Value of Rice? </li></ul><ul><li>Can have ‘organic rice’ that is free from agrochemical residues </li></ul><ul><li>Quite possibly also higher nutritional quality in terms of micronutrients – needs to be evaluated scientifically </li></ul><ul><li>Larger root system gives higher grain weight (usually 5-15% higher), also greater grain density and nutrients? </li></ul>
    41. 42. Emerging Benefits of SRI? <ul><li>5. Conservation of Rice Biodiversity ? </li></ul><ul><li>Highest SRI yields come with HYVs and hybrids – all of the yields >15 t/ha </li></ul><ul><li>Traditional / local varieties respond very well to SRI, can produce yields of 6-10 t/ha, and even more </li></ul><ul><li>Traditional rice receives higher price; higher SRI yields make them popular; ‘organic’ premium is good for export </li></ul>
    42. 44. SRI sounds ILLOGICAL <ul><li>BUT LESS CAN PRODUCE MORE by utilizing biological potentials & processes </li></ul><ul><li>Smaller, younger seedlings become larger, more productive mature plants </li></ul><ul><li>Fewer plants per hill and per m 2 will give higher yield if used with other SRI practices </li></ul><ul><li>Half as much water produces more rice because aerobic soil conditions are better </li></ul><ul><li>Greater output is possible with use of </li></ul><ul><li>fewer or even no external/chemical inputs </li></ul><ul><li>Get a different phenotype from rice genome </li></ul>
    43. 45. SRI RAISES MORE QUESTIONS THAN WE HAVE ANSWERS FOR <ul><li>This should please scientists – lot of interesting new work ahead </li></ul><ul><li>At present, Chinese scientists have done more scientific research on SRI than anybody else </li></ul><ul><li>Hope to accelerate this and link with more work around the world </li></ul>
    44. 46. SRI Experience Could Help to Us to Improve 21 st Century Agriculture <ul><li>Nurturing of roots and soil biota is relevant for most of agriculture </li></ul><ul><li>Need agriculture that is </li></ul><ul><ul><li>Less ‘thirsty’ -- better roots will help </li></ul></ul><ul><ul><li>Less dependent on fossil-fuel energy sources -- fertilizer, mechanization </li></ul></ul><ul><ul><li>Less dependent on agrochemicals -- for sake of soil & water quality, for health </li></ul></ul>
    45. 47. Thank You for Opportunity to Share Ideas With You <ul><li>More information can be obtained from SRI web site: </li></ul><ul><ul><li>http://ciifad.cornell.edu/sri/ </li></ul></ul><ul><li>Or from Association Tefy Saina: </li></ul><ul><ul><li>[email_address] </li></ul></ul><ul><li>Or from CIIFAD/Norman Uphoff: </li></ul><ul><ul><li>[email_address] </li></ul></ul>
    46. 50. SRI Data from Sri Lanka <ul><li> SRI Usual </li></ul><ul><li>Yields (tons/ha) 8.0 4.2 +88% </li></ul><ul><li>Market price (Rs/ton) 1,500 1,300 +15% </li></ul><ul><li>Total cash cost (Rs/ha) 18,000 22,000 -18% </li></ul><ul><li>Gross returns (Rs/ha) 120,000 58,500 +105% </li></ul><ul><li>Net profit (Rs/ha) 102,000 36,500 +180% </li></ul><ul><li>Family labor earnings Increased with SRI </li></ul><ul><li>Water savings ~ 40-50% </li></ul><ul><li>Data from Dr. Aldas Janaiah, IRRI agric. economist, 1999-2002; now at Indira Gandhi Development Research Institute in Mumbai; based on interviews conducted with 30 SRI farmers in Sri Lanka, October, 2002 </li></ul>
    47. 51. IWMI Data from Sri Lanka <ul><li>IWMI Evaluation (Namara, Weligamage, Barker 2003) </li></ul><ul><li>60 SRI and 60 non-SRI farmers randomly selected: </li></ul><ul><li>YIELD -- increased by 50% on average (not doing full SRI) </li></ul><ul><li>WATER PRODUCTIVITY -- increased by 90% </li></ul><ul><li>COST OF PRODUCTION (Rs./kg) -- lower by 111-209% with family labor, 17-27%at standard wage rate </li></ul><ul><li>LABOR PRODUCTIVITY (kg/hr) -- up 50% in yala (dry) season, up 62% in maha (wet) season </li></ul><ul><li>PROFITABILITY -- increased by 83-206%, depending on the wage assumed (family labor vs. paid labor) </li></ul><ul><li>RISK REDUCTION -- conventional farmers had net losses in 28% of seasons, SRI farmers in only 4% </li></ul>
    48. 53. SRI CONCEPTS CAN BE EXTENDED TO UPLAND PRODUCTION Results of trials (N=20) by Philippine NGO, Broader Initiatives for Negros Development, with Azucena local variety (4,000 m 2 area) -- using mulch as main innovation, not young plants
    49. 54. (1) ROOT SYSTEM PROMOTION <ul><li>SRI is becoming referred to in India (AP) as ‘ the root revolution ’ -- key factor </li></ul><ul><li>Roots benefit from wider plant spacing, aerated soil, more soil organic matter --from both compost and root exudation </li></ul><ul><li>Roots are supported by more abundant and diversified populations of soil biota -- bacteria and viruses produce PGRs </li></ul><ul><li>Plants are two-way streets , coevolved w/ microorganisms, dependent on them </li></ul>
    50. 55. SRI farmer in Cambodia
    51. 56. SRI farmer in Cuba -- 14 t/ha
    52. 57. Root Research Reported by Dr. Ana Primavesi (1980) <ul><li>Shoot and root growth of maize (in g) grown in hydroponic solutions (14 days), with varying nutrient concentrations </li></ul><ul><li> Shoot Root </li></ul><ul><li>100% concentration 44 7 </li></ul><ul><li>200% concentration 34 7 </li></ul><ul><li>2% concentration 33 23 </li></ul><ul><li>2% concentration when 43 56 changed every other day </li></ul>
    53. 58. (2) Contribution of SOIL MICROBIAL PROCESSES <ul><li>Microbial activity is known to be crucial factor in soil fertility </li></ul><ul><li>“ The microbial flora causes a large number of biochemical changes in the soil that largely determine the fertility of the soil.” (DeDatta,1981, p. 60, emphasis added) </li></ul>
    54. 59. Bacteria, funguses, protozoa, amoeba, actinomycetes, etc. <ul><li>Decompose organic matter , making nutrients available </li></ul><ul><li>Acquire nutrients otherwise unavailable to plant roots </li></ul><ul><li>Improve soil structure and health -- water retention, soil aggregation, aeration, pathogen control, etc. </li></ul>
    55. 60. Known Processes <ul><li>Biological nitrogen fixation (BNF) ** -- also productivity from mix of NO 3 > all NH 4 </li></ul><ul><li>Phosphorus (P) solubilization ** </li></ul><ul><li>Nutrient acquisition increases through mycorrhizal fungi associations with roots </li></ul><ul><li>Rhizobia bacteria produce hormones promoting root growth - increase yield, protein </li></ul><ul><li>Protozoa ‘graze’ on bacteria on roots and excrete excess N -- because of lower C:N ratio </li></ul><ul><li>* * Both increased by wetting and drying of soil </li></ul>
    56. 61. (3) Impact of Transplanting YOUNG SEEDLINGS <ul><li>Big effect from transplanting seedlings 8-12 days old = during the 2nd or 3rd phyllochron, before 4th phyllochron (explained by T. Katayama, 1920s-30s) </li></ul><ul><li>Avoid trauma to rice plant, especially to its roots , for maximum growth trajectory </li></ul><ul><li>DIRECT SEEDING is possible, however -- being experimented with to save labor </li></ul>
    57. 63. Effect of Young Seedlings <ul><li>@ Anjomakely Clay Soil Loam Soil </li></ul><ul><li>SS/20/3/NPK 3.00 2.04 </li></ul><ul><li>SS/ 8 /3/NPK 7.16 3.89 </li></ul><ul><li>SS/ 8 / 1 /NPK 8.13 4.36 </li></ul><ul><li>AS / 8 /3/NPK 8.15 4.44 </li></ul><ul><li>AS / 8 /3/ Comp 6.86 3.61 </li></ul><ul><li>SS/ 8 / 1 / Comp 7.70 4.07 </li></ul><ul><li>AS / 8 / 1 /NPK 8.77 5.00 </li></ul><ul><li>AS / 8 / 1 / Comp 10.35 6.39 </li></ul><ul><li>Note: All of these averages are for 6 replicated trials </li></ul>
    58. 64. Effects of SRI vs. Conventional Practices Comparing Varietal and Soil Differences
    59. 65. Conclusions <ul><li>SRI taps available genetic potentials </li></ul><ul><li>The methods can be most accessible to the poor to improve food security , but gaining with large farmers (44 ha) </li></ul><ul><li>The methodology is environmentally friendly and economically profitable </li></ul><ul><li>SRI still raises more questions than answers -- contribute to new paradigm? </li></ul><ul><li>SRI is still evolving , through farmer innovation and research evaluations </li></ul>
    60. 66. Conclusions (continued) <ul><li>SRI work proceeding on 2 tracks : </li></ul><ul><ul><li>Farmer/NGO experimentation/extension </li></ul></ul><ul><ul><li>Scientific investigations/evaluations </li></ul></ul><ul><li>SRI experience may have implications for improving other crop production : </li></ul><ul><ul><li>Improve the ROOT GROWTH of crops </li></ul></ul><ul><ul><li>Support SOIL BIOTA for plants’ benefit </li></ul></ul><ul><li>SRI could contribute to a ‘post-modern agriculture’ -- most modern agriculture because based on biological sciences </li></ul>
    61. 67. Conclusions (continued) <ul><li>SRI is ‘not finished’ -- still evolving, changing, spreading, so it is premature to make final judgment or evaluation </li></ul><ul><li>SRI methods will not be suitable everywhere -- but not a ‘niche’ innovation; suitable in all 22 districts of Andhra Pradesh </li></ul><ul><li>SRI is not speculation -- not ‘wishful thinking’ -- but a FACT </li></ul><ul><li>Question is: what use will be made of these new insights and opportunities? </li></ul>
    62. 68. Spread of SRI in Asia
    63. 69. Spread of SRI in Africa <ul><li>Madagascar : now 50,000-100,000 farmers, average about 6-8 t/ha, some double or more </li></ul><ul><li>Sierra Leone : 2.5  5.3 t/ha for 160 farmers </li></ul><ul><li>The Gambia : 2.5  7.4 t/ha for 10 farmers </li></ul><ul><li>Benin : 1.6  7.5 t/ha in controlled trial </li></ul><ul><li>Guinea : 2.5  9.4 t/ha (hybrid + SRI) </li></ul><ul><li>Interest in, but no results yet from: Ethiopia, Ghana, Mali, Mozambique, Senegal, South Africa, Tanzania, and Uganda </li></ul>
    64. 70. Spread of SRI in Latin America <ul><li>Cuba : average 8-9 t/ha; INCA trial 12 t/ha; a number of farmers have reached 14 t/ha </li></ul><ul><li>Peru : initial problems with drought, frost; 2003 results 9-11 t/ha vs. current average of 6 t/ha ( not profitable given costs of production) </li></ul><ul><li>Interest in, but no results yet from: Barbados, Brazil, Colombia, Dominican Republic, Guyana, and Venezuela </li></ul>
    65. 76. .

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