The sustainable development of rice-based production systems in Europe

A. Ferrero ^a and N.V. Nguyen^b
a Department of Agronomy, Sylviculture and Land Management, University of Turin, Italy ^b Executive Secretary, International Rice Commission, FAO, Rome, Italy

INTRODUCTION

Rice is not a major food crop in Europe; nevertheless, rice consumption slowly but steadily increased from 1992 to 2001. The total quantity of rice consumed as food in Europe rose from about 4.15 million tonnes of paddy equivalent in 1992 to about 4.77 million tonnes in 2001. The quantity of rice consumed in the Russian Federation in 2001 was 0.96 million tonnes, followed by Spain (0.52 million), Italy (0.48 million), Germany (0.46 million), France (0.44 million) and Portugal (0.27 million) (FAO, 2003).

Rice was introduced into Europe during the fifteenth century and - despite the low rate of rice consumption and a number of unfavourable economic and social factors - production continued. Given the relatively high production costs in Europe, it is hard to compete with imported rice. In addition, the population expresses increasing concern about the possible negative effects of rice production on the environment and on biodiversity.

However, the existing rice-based production systems present a number of opportunities for sustainable development. This paper provides a brief description of the rice production systems in Europe and discusses the agronomic constraints of and opportunities for the sustainable development of rice-based systems.

THE EVOLUTION OF RICE PRODUCTION

From 1992 to 2002, rice harvested area in Western Europe increased slightly from 350 000 ha in 1992 to about 420 000 ha in 1996, after which it decreased slightly in 1998 and then remained unchanged at about 400 000 ha until 2002 (Figure 1). Within Europe, the changes in the harvested area were pronounced in Greece and Spain. Rice harvested area in Greece increased rapidly between 1992 and 1997 and then experienced a rapid decline; in Spain, on the other hand, it decreased (from 1992 to 1995), increased in 1996 and then remained unchanged.

Rice harvested area in Eastern Europe declined rapidly from about 330 000 ha in 1992 to about 200 000 ha in 1996 and then remained stable for the rest of the period from 1992 to 2002 (Figure 1).

TABLE 1
Rice harvested area, yield and production in Europe, 2002

Source: FAO, 2003.

Table 1 shows the rice harvested area, yield and production in selected countries in Europe in 2002, when Western Europe (WE) produced 2.60 million and Eastern Europe (EE) only 0.59 million tonnes. However, the three top rice producers were Italy (WE), Spain (WE) and the Russian Federation (EE). Together, they contributed about 83 percent of the total rice production in Europe in 2002.

The data in Table 1 show that, in general, rice yields in Western Europe were much higher than in Eastern Europe. Within Western Europe, rice yield was highest in Greece and Spain. In Eastern Europe, yield was highest in Macedonia, which may be because of the more favourable climate. The data in Figure 2 show the evolution of rice yields in the two regions of Europe between 1992 and 2002. Rice yield in Western Europe increased steadily from 6 tonnes/ha at the beginning of the period to about 6.5 tonnes/ha at the end of the period. In Eastern Europe, rice yield remained stagnant at around 3 tonnes/ha from 1992 to 1999, finally increasing to about 3.5 tonnes/ha in 2000.

FIGURE 1
Evolution of rice harvested area in Europe, 1992-2002

Source: FAO, 2003.

FIGURE 2
Evolution of rice yield in Europe, 1992-2002

Source: FAO, 2003.

RICE PRODUCTION SYSTEMS IN EUROPE

According to the FAO classification (FAO, 1996), the primary climate in Western Europe is subtropical with a dry summer (Mediterranean climate), while the primary climate of rice production in most of Eastern Europe is temperate continental. In most of Western Europe, the main rainfall occurs during the first stages of growth (April-June) and during the harvest period. Average temperatures range from 10° to 12°C during rice germination and from 20° to 25°C during crop flowering. In most of Eastern Europe, the rice-growing season is much shorter than in Western Europe, due to the low temperature regimes. The Mediterranean climate is characterized by warm, dry, clear days and a long growing season. This climate is favourable for high photosynthetic rates and high rice yields, while its low relative humidity throughout the growing season reduces the development, severity and importance of rice diseases.

About 80 percent of the rice area is cultivated with japonica varieties. The remainder is cultivated with indica varieties (mainly "Thaibonnet" and "Gladio"). Rice is planted from mid-April to the end of May and harvested from mid-September to the end of October. Rice is usually grown on fine-textured, poorly drained soils with impervious hardpans or claypans. These soils are primarily in three textural classes: clay, clay with silt, and loam with clay and silt (each ranging from 8 to 55 percent clay). A few of the soils are loam in the surface horizon, but are underlain with hardpans. The pH is between 4 and 8, with organic matter between 0.5 and 10 percent (this last value only on a limited surface area). These soils are well suited for rice production. The low water permeability enhances water-use efficiency. In some regions (the Camargue in France, Ebro Delta in Spain etc.), soils are saline or very saline. Most of the irrigation water for European rice comes from rivers (Po in Italy, Ebro in Spain, Rhone in France, Tejo in Portugal etc.) and lakes. It is estimated that less than 5 percent of rice irrigation water is pumped from wells (areas where surface water is not available or where supplement water is required). The quality of the surface water and most groundwater is excellent for rice irrigation.

In all European countries, rice is cultivated with permanent flooding. Seed beds are commonly prepared by ploughing in autumn right after the harvest of the previous rice crop or in spring of the following year at a depth of 20 cm to incorporate the residues from the previous crop into the soil. The soil is sometimes prepared by adopting minimum tillage practices to favour weed germination in order to control them better. Precision land grading, obtained with laser-directed equipment, is an agronomic practice that has greatly contributed to better water management, and consequently to increased crop-stand establishment and improved weed control. Since the beginning of the 1960s, rice has been seeded mechanically.

In general, rice seeds are mechanically broadcasted in flooded fields. However, in about 40 000 ha, mostly in Italy, seeds are drilled to dry soil in rows. In wet-seeded rice systems, soil is dried for short periods of time after the emergence of rice seedlings to promote rice rooting and to facilitate weed control treatments. However, the rice that was planted in dry soil is generally managed as a dry crop until it reaches the 3 - to 4-leaf stage. After this period, the rice is flooded continually, as in the conventional system. In these conditions, rice has no competitive growth advantage over weeds, which can compete with the crop from the beginning of stand establishment.

The conventional irrigation system for rice production is known as a "flow-through" system. Water is usually supplied and regulated through a series of floodgates from the top-most to the bottom-most basin. Throughout the rice cultivation period, water is commonly kept at a depth of 4 to 8 cm, and drained away 2 to 3 times during the season to improve crop rooting, reduce algae growth and allow application of herbicides. Rice fields are commonly drained towards the end of August to allow harvesting.

Fertilization of the soil aims principally to restore the main plant nutrients removed by crops. Under flood conditions, nitrogen is primarily absorbed in its ammonium form. This nutrient is commonly supplied at a rate of 80 to 120 kg/ha (50 percent in pre-planting and 50 percent in post-planting), using urea or other ammonium-based fertilizers. Phosphorous and potassium are supplied in the pre-planting stage at rates of 50 to 70 and 100 to 150 kg/ha, respectively.

THE EUROPEAN RICE MARKET

The European rice market consists of long-grain indica rice and round- to medium-grain japonica rice. While Europeans have traditionally consumed mostly japonica rice, the consumption of indica rice has been increasing in recent years. Demand in north European countries is almost entirely for indica type grains. Consumption of indica rice has surpassed that of japonica rice since 1999/2000.

European rice consumption is divided between human consumption (85 percent), animal feed (7 percent), industry (3 percent), seeds (3 percent) and loss (5 percent). Human consumption has increased, while other uses are stable or decreasing (industry) (CEC, 2002). European Union (EU) consumption of milled rice equivalent (industrial uses included) reached 1.8 million tonnes for the 2000/01 marketing year (CEC, 2002). The trend in consumption of milled rice equivalent is up and reached about 5 kg per caput in 2002.

Rice produced in southern Europe is processed by the local food industry in response to the demand of Mediterranean consumers and the demand for export to northern Europe. In addition to imports from southern Europe, the food-processing industry in the north imports indica husked rice from the United States of America, Thailand, India and Pakistan. Imports have increased since 1994/95 as a consequence of the Uruguay Round, the subsequent reduction of the Basmati rice tariff and the implementation of preferential regimes. The quantity of imports from third countries, expressed in milled equivalent, rose by 30 percent from 1995 to 2000. Over the same period, exports fell by 11 percent. Since then, however, total exports have stabilized, and food aid operations have at least partially replaced commercial exports (CEC, 2002). However, according to data collected between 1997/98 and 1999/2000, internal trade quantities were twice those of external trade. Italy is the main provider (about 300 000 tonnes of milled rice equivalent), followed by Spain (about 150 000 tonnes of milled rice equivalent).

Market liberalization for rice will be applied starting in 2009. Tariff reductions will be phased in with a 20 percent cut in 2006, 50 percent in 2007 and 80 percent in 2008. In the meantime, a duty-free quota, based on previous exports to the EU, has been established, with an increase of 15 percent each year until 2009, when all tariffs and quotas will be removed. This liberalization policy was agreed upon after the introduction of the European Commission agreement of February 2001. The agreement grants duty-free access to the EU market for imports from least developed countries (LDCs) for everything but arms (EBA).

On 26 June 2003, EU agriculture ministers agreed on fundamental reforms to Common Agricultural Policy (CAP), a break in the link between subsidy and production and an allowance of preparation for full implementation of EBA from 2009. The primary aspects of CAP reform concerning rice aim to reduce the intervention price by 50 percent, limiting the amount to 75 000 tonnes per year. These reductions are compensated for by a subsidy devoted in part to environmental protection.

RICE PRODUCTION CONSTRAINTS

The most significant constraints to rice production in Mediterranean climate areas include: low temperature, water scarcity, biotic stresses, unsatisfactory grain quality, high production costs and the population's concern about the harmful effects of rice production on the environment.

Low temperature

As rice plants originate from subtropical and tropical zones, they are easily damaged by low temperatures at any growth stage from germination to ripening (Ferrero and Tabacchi, 2002). Several experiments point out that a potential yield of 10 tonnes/ha requires a density of at least 250 seedlings per m². The cool weather and strong winds during stand establishment in Mediterranean climate areas may cause partial stand loss and seedling drift, which lead to poor crop establishment. In many temperate areas, the emergence rate quite often does not exceed 30 to 40 percent of the planted seeds. Therefore, to achieve an acceptable crop stand, rice growers usually use about 200 kg/ha of seed.

This low rate of crop emergence is due primarily to the effect of anaerobic conditions on germination occurring under low temperatures. To avoid low temperatures during crop establishment stage, some growers end up with delays in crop planting. However, a delay in crop establishment leads to the occurrence of reproductive stages of the crop during periods of low temperatures during the autumn that causes the death of pollen cells at meiosis stage and subsequent grain sterility. Damage to rice yield caused by spikelet sterility could be one of the most severe in years.

Poor crop establishment under European conditions could be overcome by developing new high-yielding varieties with good tolerance to low temperatures during germination, better land levelling and water management.

Water scarcity

Water is becoming increasingly scarce in many regions of the world. Between 1700 and 2000, total worldwide water withdrawal increased more than 35 times the rate of population increase. Governments will be compelled to place severe limitations on the use of water resources, particularly in agriculture. Agriculture is by far the biggest consumer of water. Water consumption in agriculture represents about 40 percent of the total consumption in Europe, 50 percent in North and Central America and 85 percent in Asia. In the short term, the conflicting demand for water for use in industrial activities, sanitation and as safe drinking water can be expected to increase.

Many water problems are related to its uneven distribution. Other problems include pesticide pollution, soil erosion and deforestation, waterlogging in heavy soils, and increasing irrigation costs. All these constraints are forcing agronomists to develop management strategies to reduce water consumption and increase the efficiency of irrigation systems. As a result, agronomists are continually creating strategies that increase the rice yield per unit of water input. According to the estimates of the World Resources Institute, 15 percent of the water losses due to evaporation, leaching or any other inefficiency can be saved through more sensible use. Water problems can also be tackled by providing new rice varieties which are more suitable to the various conditions of water management.

Rice is more water-consuming than many other crops: in continuous flooding cultivation it consumes about six times the water required by wheat. New varieties suitable for reduced water use are needed in irrigated systems. The availability of short-cycle and high-yielding rice could successfully lower the amount of irrigation water used in continuously flooded cultivation. A more consistent reduction in water consumption could be achieved by developing profitable varieties suitable for discontinuous irrigation in all climate conditions. These conditions of water management will also contribute to the alleviation of methane emissions from rice. Non-flooded conditions, however, can lead to increased competition from weeds and increased soil salinity. The constraints on rice yield caused by weed growth and soil salinity must also be addressed as new varieties are developed.

Biotic stresses

According to Oerke et al. (1994), rice losses caused by disease, pests and weeds, despite current crop protection, account for about 50 percent of the crop potential. The numerous experiments conducted each year in European rice paddies reveal that the failure to control weeds may potentially result in the complete loss of the rice yield. The main noxious rice organisms are:

• blast (Pyricularia oyzae) and stem rot (Rhizoctonia oryza-sativae) (diseases);

• rice leafminer (Hydrellia griseaola) and tadpole shrimp (Criops longicaudatus) (animal pests); and

• Echinochloa spp., Bolboschoenus maritimus, Schoenoplectus mucronatus, Heteranthera spp., Alisma plantago-aquatica and weedy rice forms (weeds).

All these species are usually controlled with pesticides. The use of these products may, however, result in the appearance of resistant species, cause environmental pollution and risk disrupting the precarious balance of the natural enemies to pests (Ferrero et al., 2001; Ferrero, Tabacchi and Vidotto, 2002).

Weed resistance to herbicides has been reported in Italy, Spain, France and Greece. For example, a few years after the introduction of sulfonylurea herbicides, some species began to develop resistance to acetolactate synthase inhibitors. This phenomenon was first noticed in 1995 in A. plantago aquatica and S. mucronatus plants, and was continuously treated for at least 3 years. The studies of Sattin et al. (1999) on S. mucronatus have shown that there is a cross-resistance among several sulfonylureas (azimsulfuron, bensulfuron-methyl, cynosulfuron and ethoxysulfuron). Some of these resistant populations appeared to be sensitive to triazolopyrimidine herbicide (metosulam) at very high dosages (three times the recommended field dose). In Italy, weed resistance was reported on a rice surface of more than 15 000 ha (Ferrero, Tabacchi and Vidotto, 2002).

A solution to these issues could be the development of rice cultivars that are resistant to pests and diseases, highly competitive against weeds, with allelopathic traits, and tolerant to safe and wide spectrum herbicides (Ferrero et al., 2001). The use of these varieties combined with prophylactic measures could be a sound strategy for preventing damage.

Grain quality

The quality of rice is not always easy to define as it depends on a combination of many subjective and objective factors, largely related to the consumer and the intended end use of the grain. The demand by the consumer for better quality has notably increased in the more economically developed countries of Europe, giving rice producers the opportunity to increase the total economic value of rice. Quality traits are also related to the taste of the several ethnic groups that make up European society.

Grain quality is influenced either by characteristics of variety or the crop production environment, harvesting, processing and milling techniques. The main key components of rice quality are listed in Table 2. Some of these have also been defined by EC (European Community) regulations, which have recently come into force. The regulations relate to the common organization of the rice market.

Many characteristics of grain quality are related to rice grain shape. Since rice is consumed in grain form, the physical dimensions and weight are among the first criteria of rice quality that breeders consider when developing new varieties. Grain type categories are based upon three physical traits: length, width and weight. According to EC regulations, only length and width and their ratio are formally considered. In the United States of America, however, grain weight is also taken into consideration (Table 3). Long slender grains usually have greater breakage than short grains and consequently give a lower milling yield.

The demand for long-grain varieties increased significantly as a result of food diversification and immigration (Tran, 1996). The EC further encouraged this demand through the allocation of subsidies to rice growers planting indica type rice. Subsidies were originally given to compensate for lower paddy and milling yields. The variety was often recorded in comparison to japonica varieties. To meet this demand, many long-grain varieties have been introduced in European countries. All these varieties are suited to temperate climatic conditions even if they are sometimes damaged by low night temperatures, occurring particularly during the flowering period (Ferrero, Tabacchi and Vidotto, 2002).

Grain shape is usually associated with specific cooking characteristics. Cooked long-grain rice is fluffy and firm, while medium and short-grain rice is soft, moist and sticky in texture. The demand among consumers in Europe is higher for long-grain rice.

Grain fissuring is often due to overexposure of mature paddy to fluctuating temperature and moisture conditions. Cracks in the kernel are the most common cause of rice breakage during milling. Milling degree is influenced by grain hardness, size and shape, depth of surface ridges, bran thickness and mill efficiency. Wholegrain milling yield is the percentage of intact kernels to broken kernels after milling and separation. Producers are paid less for broken kernels than for whole.

Other specific quality traits are usually required for the production of processed rice, such as parboiled, quick cooking or precooked rice and rice flour. Rice parboiled for consumption as table rice is generally a long-grain variety. Medium-grain rice is also parboiled, but it is more commonly ground into flour for use as an ingredient in food products (baked crackers, fried snacks).

TABLE 2
Main components of rice quality in Europe

TABLE 3
Range of grain size among typical European and United States long-, medium- and short-grain rice

Aroma is an important qualitative trait in specific varieties (Basmati type). Rice of this type is generally long-grain with high grain quality. It has an aroma often described as being "popcorn-like". The grains become very long and thin and maintain a moderately firm texture after cooking. Demand for aromatic rice varieties has shown a significant increase since the early 1990s, primarily in the United Kingdom and other European countries, but also with a significant presence in Asiatic communities, (Faure and Mazaud, 1996). It seems reasonable to expect afurther increase in aromatic rice consumption throughout Europe in the years to come, because of the increase in people migrating from Far East countries and the growing interest in ethnic cuisine. European consumption of Basmati rice is met entirely by imports from India and Pakistan. For this reason, specific research programmes need to be set up in order to develop aromatic varieties suited to European climatic conditions.

European consumers are showing a growing interest in special rice varieties, such as organic rice, waxy rice, Jasmine-type rice, wild rice and coloured (red, black) pericarp. At present, the demand for these products only accounts for a small share of the market, with the exception of organic rice. Organic rice has already found a place in market demand, and its demand is expected to increase in the short to medium term. The yield obtained in organic rice systems is usually 25 to 30 percent lower than that obtained in ordinary cultivation, mainly because of the great difficulty in controlling weed infestations.

Lodging resistance has been a key target trait for raising yield potential. It is associated with traits such as plant height, stem strength and thickness. Lodging-resistant rice cultivars usually show slow grain filling when nitrogen is applied in large amounts. Many other problems, such as variable milling yield, grain fissuring, grain shedding and non-contemporaneous maturity, are sometimes closely linked to the genetic features of the rice varieties, and are also related to other agronomic constraints, such as cold temperature and lodging.

High production costs

The cost of rice production in Western Europe is generally much higher than in most Asian countries, with the exception of Japan. The production cost per tonne of paddy rice in Europe is also higher than in the United States of America. The high production cost in Europe compared with the United States of America was largely due to the high expenses relating to fertilizer, seed, crop protection products, custom application, fuel and labour. The cost of production in the United States of America can range from US$104 to 180 per tonne (Salassi, 2002), while in Italy the cost is about 200 per tonne (AIDAF-VC/BI, 2003).

Population's concern

The increase in number of mosquitoes and concern for the spread of malaria was a major reason for the restriction of rice production in the past. There is increasing concern related to the negative effects of rice production on the environment (especially the emission of methane gases which cause global warming) and the harmful effects of pesticide application on agricultural biodiversity in rice-based production systems. This new concern may lead to further restrictions in rice production in the continent. Integrated management systems for efficiency in input utilization, including the use of water, need to be promoted in rice production in Europe. Also, the promotion of agricultural biodiversity in rice-based production systems, such as rice-livestock and rice-other crops, is desirable.

OPPORTUNITIES FOR SUSTAINABLE RICE PRODUCTION

One of the most effective means of addressing the issues in rice cultivation and raising the average yield at farm level is through research and subsequent dissemination of the resulting data. Numerous research programmes at national or European level have been set up throughout Europe. They cover the whole rice sector, from agronomic practices and breeding aspects to quality and market problems. Much of the research done in Europe has been fostered by MED-RICE (Inter-regional Cooperative Research Network on Rice in the Mediterranean Areas).

Advances in rice research

Rice science has made considerable progress. In the area of rice varietal improvement, recent advances in hybrid rice and new rice for Africa (NERICA) are just two examples of the successful contributions of science to the development of rice. Scientists at IRRI have continued working to increase the genetic yield potential of tropical rice through the concept of new plant types (NPT) with the stated goal of increasing the yield potential to between 12 and 15 tonnes/ha (Fisher, 1996; Peng, Khush and Cassman, 1994). The recent success in rice genome mapping has further increased the potential for the application of science. The increase in the yield potential of rice, the tolerance/resistance of rice to disease, weeds and pests, as well as tolerance to drought and salinity, could be achieved without harming the environment (Khush and Brar, 2002). However, these opportunities have also created new imperatives for biosafety, field-testing and capacity-building within nations to ensure that the new innovations benefit local people and do not incur long-term costs to the environment.

Most existing rice varieties have a potential yield that exceeds actual yield. Furthermore, there is considerable variation in the actual yield levels achieved even under similar production systems. The gap reflects numerous deficiencies resulting primarily from inadequate crop, nutrient and water management practices. During the 1990s, several systems were developed to allow a higher level of integrated crop management practices in rice production. The application of these rice integrated crop management (RICM) systems has increased rice yield and reduced cost and environmental degradation through more efficient application of inputs. From 1973 to 1985, rice yield in Australia remained stagnant at around 6 tonnes/ha. The RICM system, "RiceCheck", was developed and transferred in 1986 (Clampett, Williams and Lacy, 2001). With the wide adoption of RiceCheck, the Australian national yield increased rapidly and steadily from about 6 tonnes/ha in 1987 to 9.65 tonnes/ha in 2000 (Figure 3). According to Australian rice scientists, half of the observed yield increase since 1986 can be attributed to the adoption of new rice varieties and another half to the adoption of RiceCheck (Nguyen, 2002). The development and dissemination of RICM systems in Europe could help to lower production costs per tonne of paddy and to minimize environmental degradation.

FIGURE 3
Australian rice yield, 1970-2000

Source: FAO, 2001.

MED-RICE

Rice cultivation in Mediterranean climate areas has had to face strong competition in the world market. In the local market, demand for speciality and quality rice has become more and more common. To tackle these challenges, institutions from Europe and the Near East have improved scientific cooperation while trying to capitalize on the wide range of experience and potential in each country.

Relationships among rice scientists from many of the countries with a Mediterranean climate are strengthened through scientific gatherings sponsored by the Interregional Cooperative Research Network on Rice in the Mediterranean Areas. The network, known as MED-RICE, began as a response to the need for collaboration and coordination in research on rice in view of its increasing cultivation and consumption in Europe. Some of the issues dealt with include:

• the quality and competition of European rice;

• resistance to blast, water shortage, stem borers and disease;

• control of red rice;

• cataloguing of rice genetic resources in the region; and

• a data bank of knowledge on all aspects of rice cultivation for the purpose of improved management and rice yields.

These issues are all being addressed through cooperative research programmes between member institutions of the network. Sixteen countries participate in MED-RICE: Bulgaria, Egypt, France, Greece, Hungary, the Islamic Republic of Iran, Italy, Morocco, Portugal, Romania, the Russian Federation, Spain, Turkey, the United Kingdom, Ukraine and Uzbekistan. MED-RICE activities include scientific meetings, cooperative research programmes and publications, ranging from reports and proceedings to a newsletter (Medoryzae). The network's Web site can be found at http://medrice.agraria.unito.it

CONCLUSIONS

Rice is not among the major food crops of Europe; however, rice consumption as food is slowly but steadily increasing. Since its introduction, rice production has remained in Europe, despite the low rate of rice consumption and a number of unfavourable economic and social conditions. The cost of rice production in Europe remains relatively high, making competition with imported rice difficult. In addition, concern over the negative effects of rice production on the environment and biodiversity has continued to increase. However, the rice-based production systems in Europe have a number of opportunities for sustainable development.

A sustainable increase in rice production in Europe and North Africa requires strategies that must focus on the following:

• Collaboration among rice research institutions towards the adoption of modern plant breeding technology to develop new generations of high-yielding varieties with better grain quality and with better resistance or tolerance to biotic and abiotic stresses.

• Promotion and development of rice integrated crop management (RICM) systems for improving productivity and reducing the production cost per unit of output.

• Promotion and adoption of production technologies and systems that aid the conservation of biodiversity and the environment.

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