Agricultural Officer (Rice Agronomy), FAO Crop and Grassland Service, Rome, Italy
The development of high-yielding rice varieties has led to the green revolution in a number of rice producing countries. Before 1950, farmers in tropical climate areas of Asia planted mostly traditional indica varieties and yields from farmers' fields rarely exceeded 2.5 tonnes/ha. Varietal improvement activities, especially since 1950, have increased the yield potential of rice varieties. The first high-yielding variety, IR8, was developed in 1966. During the 1966 dry season at the experimental farm of the International Rice Research Institute (IRRI), Los Baños, the Philippines, IR8 yielded 10.3 tonnes/ha (De Datta, 1981). Tests carried out on IR8 at rice experiment stations across tropical Asia indicated yields of 4-8 tonnes/ha (Chandler, 1979). However, evidence demonstrates that factors other than rice varieties have also contributed greatly to the success of rice production during the green revolution. Duwayri, Tran and Nguyen (1999) reported that rapid yield growth in Asia was obtained only during the 1980s, regardless of the release of IR8 in 1968 and series of other high-yielding rice varieties by IRRI and national research systems in Asia during the 1970s.
In rice production, after the selection of a variety to plant, farmers carry out a large number of activities during the season. These include: (a) selection of seeds; (b) determination of the date to establish the crop and cropping calendar; (c) land preparation; (d) establishment of the crop; (e) protection of the crop from weeds, insects, diseases and other enemies; (f) provision of nutrient to the crop; (g) provision of water to the crop; and (h) harvest. The managing of these activities is called crop management. The results of rice research during the past 50 years have firmly established that, at farm level, rice yield is determined to a large extent by crop management. Packages of production technologies were formulated and transferred to farmers during the 1970s and 1980s. The application of these packages of production technologies in the cultivation of high-yielding varieties has resulted in a substantial increase in rice production during the 1980s. However, it has also led to the development of undesirable effects on sustainable rice production, such as new pests and pest-pressures, mining of soil fertility and degradation of the environment. Subsequently, integrated pest management (IPM) and integrated nutrient management (INM) systems have been developed and transferred to support sustainable rice production for food security. Recently, a number of national and regional rice programmes have also been developed and transferred to improve crop management systems for productive and environmentally friendly rice production. The following sections present a summary of the systems for crop management in rice production and the development of productive and environmentally friendly rice integrated crop management (RICM) systems.
During the 1970s and 1980s a number of packages of production technologies were formulated and transferred to farmers for the cultivation of high-yielding rice varieties under different ecosystems in different locations. The major characteristics of these packages of production technologies are as follows:
An example of the packages of production technologies formulated during the 1970s is shown in Box 1. The application of these packages in the cultivation of high-yielding varieties has helped to increase rice yield and production substantially. The growth rate of rice yield in Asia increased from 1.88 percent per year in the 1970s to 2.86 percent per year during the 1980s (Duwayri et al., 1999). The application of these packages of production technologies during the green revolution, however, has also produced negative effects on sustainable rice production.
|
BOX 1
Source: Cardenas et al., 1980 |
The blanket application of insecticides as recommended in the packages of production technologies formulated and transferred during the 1970s and 1980s resulted in the elimination of a wide array of beneficial micro-organisms or natural enemies of insects in rice fields. It also promoted the development of new pest biotypes. Similarly, the capacity of weed species to resist chemical herbicides after a period of repeated application was increasingly reported. The IPM systems for the protection of rice crops from insects were developed in the second half of 1980s. These view rice crops in a holistic way. Emphasis is placed on field observation and diagnosis in the incipient stage of insect attack. The complexity of mixed infestations and/or infections is observed and discussed. Farmers are educated on the role of natural enemies of the pests and taught how to make decisions regarding the need to use pesticides or not, based on field observation and diagnosis. The IPM systems have become popular with farmers in many countries, especially in Asia. Since then, these systems have been extended to cover the management of diseases, weeds and other biological enemies of rice. They have been considered not only to be economical but also environmentally friendly as they help to minimize the harmful effects of pesticides on the environment and humans.
Similarly, the heavy use of chemical fertilizers in rice production during the 1970s and the 1980s, especially nitrogen fertilizers, has led to increased nutrient deficiency of phosphorus, potassium, zinc and other nutrient elements. The application of high rates of chemical fertilizers, coupled with inefficient application, has polluted the environment through the leaching of the applied nutrient to rivers, lakes and other water bodies.
The INM systems for rice production were then developed and popularized. These systems take into account the level of soil fertility and other agro-ecological conditions during the rice cropping season as well as the property of the variety in use when formulating the fertilizer combination for application to rice crops. The INM systems also promote the balanced application of fertilizers and the integration of organic fertilizer such as green manure and compost into the provision of nutrients to the rice crops (Shastry et al., 1996).
The IPM and INM systems, however, only deal with one aspect of the management of the rice crop: the IPM systems deal with the protection of rice crops from pests, while the INM systems deal with the provision of nutrients to rice crops. Therefore, they can only partially improve the management of the rice crop. As a result, efforts have been made to develop the packages of production technologies further. During the 1990s, a number of improved crop management systems were developed and transferred to rice farmers in several countries: Australia (Lacy et al., 1993; Clampett, Williams and Lacy, 2001), Burkina Faso (Nguyen et al., 1994), Egypt (Badawi, 2001), the Republic of Korea (Moon, 2001) and Senegal (Nguyen, 2001). The Irrigated Rice Programme of the West Africa Rice Development Association (WARDA) has also developed integrated crop management systems for irrigated rice production in the Sahel zone of West Africa (Wopereis et al., 2001), and FAO's Global IPM Programme has, in the last few years, promoted the application of integrated production and protection management (IPPM) systems for pest management in crop production.
Among the recently developed packages of production technologies, the RICECHECK system is the most outstanding in terms of its innovation and success in raising productivity. RICECHECK was developed and transferred by the Australian rice programme in 1986. It covers seven areas of crop management or component factors: field layout, sowing time, crop establishment, crop protection, crop nutrition, water management and harvest grain quality (Box 2).
From 1973 to 1985, rice yield in Australia stagnated at around 6 tonnes/ha (Figure 1). During the 1980-84 period, Calrose, a tall-strawed, medium-grain variety, accounted for 60-77 percent of total production. The yield distribution data for Calrose crops in the 1981/82 season showed a wide variation of yields among individual rice farms. The average yield of 1 343 rice farms in the Murray Valley region was 6.8 tonnes/ha. The average yield of the 10 percent highest-yielding rice farms was more than 9 tonnes/ha, while that obtained by the 25 percent lowest-yielding rice farms was less than 5.25 tonnes/ha. The highest-yielding 10 percent of farms achieved yields some 50-60 percent higher than those of the lowest 25 percent yielding farms (FAO, 2001a).
FIGURE 1
Australian rice yield 1970-2000
After the transfer of RICECHECK in 1986, the Australian national yield increased rapidly and steadily from about 6 tonnes/ha in 1987 to 9.65 tonnes/ha in 2000 (Figure 1). The Australian rice yield in 2000 was the world's highest national yield (FAO, 2001a). Australian rice scientists considered that half of the observed yield increase since 1986 can be attributed to the adoption of new rice varieties and the other half to the adoption of RICECHECK (FAO, 2001b). Data obtained from field surveys showed the importance of managing the rice crop in an integrated manner for increasing productivity. Figure 2 shows that the more checks successfully applied or achieved by farmers, the higher the yield.
The results obtained in Australia also showed that both rice yield and the efficiency of nitrogen fertilizer application in rice production were obtained with the application of RICECHECK (Batten, Blakeney and Ciaverella, 1994). The increase in nitrogen efficiency, in turn, reduced not only production costs but also the negative effects of nitrogen losses on the environment.
BOX 2 1. FIELD LAYOUT: "the foundation of successful rice growing" 2. SOWING TIME: "sowing on time gives maximum yield potential every year" 3. CROP ESTABLISHMENT: "the first step of the yield ladder" 4. CROP PROTECTION: "weeds and pests reduce yields" 5. CROP NUTRITION: "the Split Nitrogen Strategy - two steps important to high yields" 6. WATER MANAGEMENT: "the right depth at the right time" 7. HARVEST GRAIN QUALITY: "management affects the results" Source: Lacy et al., 1993. |
In the first instance, RICECHECK appears to be another package of production technologies. However, a close examination would reveal many innovations in crop management in RICECHECK. For each of the management activities, RICECHECK provides both input and output recommendations (Box 2). The input recommendations are similar to those in other improved packages of production technologies and those in IPM and INM systems. The input recommendations in RICECHECK (for example rate of N fertilizer) are flexible and take into consideration observation of the actual conditions of the crop at the time of application in deciding the type and rate of input application (for example, the nitrogen content in leaf tissues and the number of shoots per unit area).
However, the RICECHECK output recommendations are the new innovation in crop management. They inform farmers on what they are expected to obtain or need to achieve (e.g. number of plants/m2, leaf nitrogen content, yield) from the application of input recommendations. They provide criteria for farmers to evaluate if the input recommendations for a management factor at a given stage of crop development were properly carried out. With output recommendations farmers could recognize when, where and what went wrong in order to improve the crop management in subsequent cropping seasons.
FIGURE 2
Relationship between yield and the achievement of
KeyChecks of 1 834 Amaroo rice crops over the six seasons 1994-99
Rice production, so far, has been able to meet the demand of the world's population. However, the world's population still continues to grow at a high rate. On the other hand, the land and water resources for rice production are becoming increasingly scarce. The annual growth rate of the world's rice harvested area has been well below 0.5 percent during the last two decades. Sustainable rice production for the food security of the world's population in the near future, therefore, requires systems for rice crop management that are both productive and environmentally friendly. The experiences gained through the development and application of crop management systems in rice production, especially the IPM and INM systems and RICECHECK, indicate the possibility of developing productive and environmentally friendly rice integrated crop management (RICM) systems. The following technical norms or rules need to be taken into account during the formulation of such RICM systems:
The formulation of RICM systems needs to be done in participatory mode, involving researchers, extension officers, farmers and other stakeholders. The following guidelines could be used:
At present, the indicators or indexes of resource conservation and environmental protection are not well developed. Therefore, in order to develop environmentally friendly RICM systems, efforts and resources should be applied to the development of quantifiable data such as water pollution caused by the application of insecticides, herbicides and fertilizers; the salinization of rice soils caused by irrigation and other indexes or indicators of environmental degradation.
The farmer discussion group or farmers' field school (which is being popularized by FAO) could be used for the transfer of RICM systems. They can provide a forum for the presentation of relevant technology, farmer-centred discussion, collaborative learning and feedback on the applicability of the technology. A researcher or extension officer serves as both an expert/resource person and a facilitator for the discussion group. Through discussion groups, farmers can learn from each other as well as from the researcher or extension officer. The extension officer also learns through the discussion groups and completes the link by sharing the new knowledge with research colleagues. Local agribusiness advisers should also be encouraged to participate in the group meetings. Four to five meetings of a rice discussion group could be organized for each season. The following is a typical sequence of group meetings for the transfer of RICECHECK in Australia (FAO, 2001f).
Badawi, A.T. 2001. Yield gap and productivity decline in Egypt. In Yield gap and productivity decline in rice production. pp. 429-442. Proceedings of the Expert Consultation held in Rome, 5-7 September 2000. Rome, FAO.
Batten, G.D., Blakeney, A.B. & Ciaverella, S. 1994. An interactive database for use with the rice tissue test service. In E. Humphreys, E.A. Murray, W.S. Clampett & L.G. Lewin, eds. Temperate rice - achievements and potential. pp. 473-476. Proceedings of Temperate Rice Conference, February 1994. Yanco, NSW, Australia. Griffith, NSW, Australia, Temperate Rice Conference Organising Committee.
Cardenas, A.C., Dilag, R.T. Jr, Pantastico, E.B. & Haws, L.D. 1980. An approach to rainfed farming: the Philippine case. Manila, Philippine Council for Agriculture and Resources Research and Bureau of Agricultural Extension, Ministry of Agriculture.
Chandler, R.F. Jr. 1979. Rice in the tropics: a guide to the development of national programme. Boulder, Colorado, USA, Westview Press.
Clampett, W.S., Williams, R.L. & Lacy, J.M. 2001. Major achievements in closing yield gaps of rice between research and farmers in Australia. In Yield gap and productivity decline in rice production. pp. 441-428. Proceedings of the Expert Consultation held in Rome, 5-7 September 2000. Rome, FAO.
De Datta, S.K. 1981. Principles and practices of rice production. New York, USA, Wiley. 618 pp.
Duwayri, M., Tran, D.V. & Nguyen, V.N. 1999. Reflections on yield gaps in rice production. IRC Newsletter 48: 13-26
FAO. 2000. Training on hybrid rice in China, by K.S. Rao. A report submitted to FAO after the training session from 6 September to 15 November 2000 in Jiangxi Academy of Agricultural Science, Nanchang, China.
FAO. 2001a. FAOSTAT 2001, available at www.fao.org 2001
FAO. 2001b. Consultancy report on a mission to West Africa, August 2001, by W.S. Clampett. Rome.
Lacy, J., Clampett, W.S., Lewin, L., Reinke, R., Batten, G., Williams, R., Beale, P., McCaffery, D., Lattimore, M., Schipp, A., Salvestro, R. & Nagy, J. 1993. 1993 Ricecheck recommendations. NSW Agriculture and Rice Research and Development Committee, Australia. 16 pp.
Lacy, J.L., Clampett, W.S., Lewin, L., Reinke, R., Williams, R., Beale, P., Fleming, M., Murray, A., McCaffery, D., Lattimore, M., Schipp, A. & Salvestro, R. 2001. 2001 Ricecheck recommendations. Australia, NSW Agriculture and Rice Research and Development Committee. 16 pp.
Moon, H.P. 2001. Yield gap and productivity decline in the Republic of Korea. In Yield gap and productivity decline in rice production. pp. 345-356. Proceedings of the Expert Consultation held in Rome, 5-7 September 2000. Rome, FAO.
Mouret, J.C. & Hammond, R. 2001. Analyse de la variabilité des rendements en relation avec les techniques culturales. IRC Newsletter 50: 37-42.
Nguyen, V.N. 2001. Technology transfer for irrigated rice production in the Senegal River valley under the Special Programme for Food Security. IRC Newsletter 50: 67-72.
Nguyen, V.N., Tran, D.V., Bautista, R.V., Maiga, M. & Weerapat, P. 1994. Thriving with rice technologies for small farmers in irrigated systems in sub-Saharan Africa. IRC Newsletter 43: 33-39
Shastry, S.V., Tran, D.V., Nguyen, V.N. & Nanda, J.S. 1996. Sustainable integrated rice production. In Progress assessment and orientation in the 1990s. pp. 45-58. Proceedings of the 18th Session of the International Rice Commission held in Rome, 5-9 September 1994. Rome, FAO.
Wopereis, M.C.S., Hafele, S.M., Kebbeh, M., Miezan, K. & Diack, B.S. 2001. Improving the productivity and profitability of irrigated rice production in Sahelian West Africa. In Yield gap and productivity decline in rice production. pp. 117-142. Proceedings of the Expert Consultation held in Rome, 5-7 September 2000. Rome, FAO.
Systèmes productifs de gestion intégrée, respectueux de l'environnement
Au niveau des exploitations, le rendement du riz est déterminé dans une grande mesure par la gestion des cultures. Pendant les années 70 et 80, des séries intégrées de technologies de production ont été mises au point et transmises aux agriculteurs pour la culture des variétés de riz à haut rendement. L'application de ces programmes a entraîné un accroissement substantiel de la production de riz. Toutefois, l'application systématique d'insecticides, comme cela était recommandé, a entraîné la disparition de micro-organismes bénéfiques et a encouragé le développement de nouveaux biotypes de ravageurs. Des systèmes de protection intégrée ont donc été mis au point. De même, l'utilisation massive d'engrais chimiques et surtout d'engrais azotés dans la production de riz, a conduit à des carences en phosphore, en potassium, en zinc et en d'autres substances nutritives. Les systèmes de gestion intégrée des éléments nutritifs ont été mis au point et diffusés. Récemment, des systèmes améliorés de gestion des cultures ont été élaborés et transmis aux riziculteurs notamment RICECHECK, qui est le plus intéressant. Après son introduction en Australie en 1986, les rendements ont augmenté rapidement, passant d'environ 6 tonnes/ha en 1987 à 9,65 tonnes/ha en 2000. Des enquêtes de terrain ont montré l'importance de la gestion intégrée de la riziculture pour accroître la productivité. Les recommandations de résultat de RICECHECK sont les dernières innovations en matière de gestion des cultures. Elles indiquent aux agriculteurs ce qu'ils peuvent espérer obtenir à chaque étape de croissance et les aident à déterminer quand, à et pourquoi, des problèmes se sont présentés, afin d'améliorer la gestion des cultures au cours des prochaines campagnes. L'expérience indique qu'il est possible d'élaborer des systèmes de gestion intégrée de la riziculture, à la fois productifs et respectueux de l'environnement.
Sistemas productivos y ecológicos de manejo integrado de los cultivos de arroz
En el ámbito de la explotación agrícola, el rendimiento del arroz está determinado en gran medida por el manejo del cultivo. Durante las décadas de 1970 y 1980, se formularon conjuntos de tecnologías de producción que se transfirieron a los agricultores para el cultivo de variedades de arroz de alto rendimiento. La aplicación de estos conjuntos ha provocado un notable aumento de la producción arrocera. Sin embargo, la aplicación generalizada de insecticidas, que se recomendaba en estos conjuntos, dio lugar a la eliminación de microorganismos benéficos y promovió el desarrollo de nuevos biotipos de plagas, lo que motivó el desarrollo de los sistemas de Manejo integrado de plagas (MIP). Asimismo, la utilización intensiva de fertilizantes químicos, especialmente los nitrogenados, ha provocado una deficiencia de fósforo, potasio, zinc y otros elementos nutrientes en la producción de arroz. Por ello, se desarrollaron y popularizaron sistemas de Manejo integrado de nutrientes (MIN). Recientemente, se han desarrollado sistemas mejorados de manejo de cultivos que se han transferido a los productores de arroz. Entre ellos, uno de las principales es el RICECHECK. Después de la transferencia de RICECHECK en 1986, los rendimientos de arroz aumentaron rápidamente en Australia, de unas 6 toneladas por hectárea en 1987 a 9,65 en 2000. Reconocimientos sobre el terreno demostraron la importancia del manejo del cultivo del arroz de forma integrada para incrementar la productividad. Las recomendaciones sobre el producto de RICECHECK son la última innovación del manejo de cultivos. Ofrecen información sobre lo que los agricultores pueden esperar obtener del manejo de cultivos en cada etapa del crecimiento y les ayudan a reconocer cuándo, dónde y en qué se equivocaron al tratar de mejorar el manejo del cultivo a fin de corregirlo en campañas posteriores. La experiencia adquirida indica la posibilidad de desarrollar sistemas productivos y ecológicos de manejo integrado del cultivo del arroz.
