ARTICLE
Auteur(s) : Aldo
Ferrero
Dipartimento di Agronomia, Selvicoltura e Gestione del
Territorio, Via Leonardo da Vinci, 44, 10095 Grugliasco, Italy
During the last 10 years rice cultivation in the European Union has
remained roughly unchanged at about 400,000 ha (table 1). The two top rice producers are Italy
(224,000 ha) and Spain (117,000 ha). These two countries
together contribute more than 80% of the total rice production in
Europe. Some slight variations in the harvested area have been
recorded in each country of cultivation, in relation to the market
price or water availability. According to the last estimates in the
2006 season the global area of cultivation should record a slight
reduction, with a moderate increase (about 4,000 ha) in Italy
and a significant reduction in Spain (17,000 ha) because of
limited water supply.In most countries rice production mostly
occurs in concentrated areas such as, the Po valley in Italy, the
Rhone delta in France, the Tessaloniky area in Greece. In Spain and
Portugal rice cultivation is scattered in several areas such as the
Aragon area, the Ebro delta, the Valencia Albufera, the
Guadalquivir valley in Spain, the Tejo and Mondego valleys in
Portugal.The other major non-EU rice-producing countries in Europe
or in the Mediterranean region are Egypt (660,000 ha) and
Turkey (80,000 ha) (table 1) (figure 1).In
2005 the average crop yield was quite variable as it ranged from
7.3 t/ha (Greece) to 4.8 t/ha (Portugal) in the EU and
from 9.8 (Egypt) to 4.4 (Ukraine) in other non-EU and Mediterranean
countries. In Egypt the average yield has increased dramatically in
the past 20 years, from 5.7 t/ha, in 1985 to 8.2 in 1995
and 9.8, in 2005.The ecological conditions of rice cultivation are
quite variable. In Italy, the climate of rice production is
temperate-continental, with a cold winter and warm summer and main
rainfall occurring during the first stages of the crop growth
(April-June) and the harvesting period (September-October) (FAO,
1996). In most of the other countries the climate is sub-tropical
(Mediterranean climate) with a dry summer and warm, dry, clear days
and long growing season. Rice is primarily grown on fine-textured,
poorly drained soils with impervious hardpans and claypans that are
not much suitable to other crops. A few of the soils are sandy in
the surface horizon, but are underlain with hardpans. The pH can
range from 4 to 8 and organic matter from 0.5 to 10%. In most
coastal areas soils are saline or very saline (e.g. the Camargue in
France, Ebro delta in Spain). In these conditions rice growing has
virtually become a single crop business.Rice is planted from early
April to end-May and harvested from mid-September to end October.
During all or almost all cycle of cultivation rice fields are
maintained flooded, mainly to protect the plant from the low
temperatures, avoid fast temperature variations and limit weed
growth. The level of the water varies over the cultural season. It
is kept at 5-7 cm during the first stages of the crop growth,
in order to promote rice growth and root anchorage and at
10-15 cm after rice tillering, mainly to avoid pollen
sterility effects caused by low temperatures during crop flowering.
Throughout the rice cultivation season, water is usually drained
away 2-3 times to improve crop rooting or allow fertilization and
herbicide spraying. About 20-30 days prior to harvesting rice
fields are completely drained to facilitate harvesting operations.
In about 40,000 ha, mostly grown in Italy, seeds are drilled
to dry soil in rows. Starting from the 3-4 leaf stage the rice
is flooded continually, as in the conventional system. Most of the
irrigation water comes from rivers (Po in Italy, Ebro and
Guadalquivir in Spain, Evros in Greece, etc.) and lakes (Albufera
in Spain). According to the different management conditions the
water requirements over a cultural season varies considerably from
18,000 to 40,000 m3/ha.Precision land grading,
obtained with laser-directed equipments, is an agronomic practise
that has greatly contributed to better water management, and
consequently to increase crop stand establishment and improved weed
control.Seedbeds are frequently prepared by ploughing at about
20 cm in depth in autumn right after the harvest of the
previous crop.In Western Europe rice seeds are soaked in water for
24 hours before planting and then mechanically broadcasted in
flooded fields. Unsoaked seeds may float on the water surface and
distribute unevenly in the field. In most countries planting
operation is carried out by ground equipments, in Spain frequently
by airplane.Fertilization is mostly carried out by supplying
mineral fertilizers (100, 50, 100 kg/ha of N; P, K,
respectively). Surveys carried out in north-west Italy pointed out
that soil reaction of paddy soils is poorly related to the
agronomic practises. As consequence of the massive use of
fertilizers, in several sites the phosphorous content is very high,
and could represent and environmental issue for surface water.About
70% of the European rice area is planted with japonica varieties
and the remainder with indica-type varieties.
Cultivation constraints
Rice productivity in European regions is affected by numerous
constraints. Most of them are related to water availability, low
temperature conditions and biotic and environmental stresses.
Main water problems are referred to a looming water shortage,
uneven distribution, nitrate and pesticide pollution, waterlogging
in heavy soils and the increasing costs of irrigation systems. The
water problems can be tackled by developing more efficient water
management strategies and providing new rice varieties that are
more suitable for a reduced use of water (Ferrero, 2002). A
consistent reduction of water consumption could be obtained by
introducing short-cycle and high-yielding rices or profitable
varieties that are suitable for discontinuous irrigation in all
rice cultivation areas. These water management conditions could
also contribute to the mitigation of methane emission due to rice
field submergence. The new varieties should however also show a
great capacity to suppress weed growth and tolerate soil salinity,
as the cultivation in non-flooded conditions usually results in an
increased competition of the weeds and a rise of soil salinity due
to upward salt migration.
As rice plants originate from sub-tropical and tropical zones,
they are easily damaged by low temperatures at any growth stage
from germination to ripening (Kaneda and Beachell, 1974). Low
temperatures at planting time, combined with the soil anaerobic
conditions frequently result in a slow and poor crop establishment
(Barbier, 1996). This in turn can result in a delay of the heading
stage with a high risk of devitalization of the pollen cells at the
meiosis stage. Furthermore rice will also be subjected to a cool
autumn and this will result in poor ripening. Even high
temperatures may result in spikelet sterility, which can vary
according to the plant growth stage.
The constraints of the poor crop establishment could be overcome
by planting rice in dry soil, whenever possible, and developing new
varieties with early vigour and good tolerance to low temperatures
during germination.
Rice is affected by the attack of weeds, diseases and insects.
The failure to control these biotic stresses may potentially result
in the complete loss of the yield (Oerke et al., 1994).
Noxious organisms are usually controlled with pesticides. The use
of pesticides, mainly herbicides, may result in the appearance of
resistant species (Busi et al., 2004), cause environmental
pollution (Ferrero et al., 2001) and risk disrupting the
precarious balance of the natural enemies to pests. The most
successful ways of tackling main issues in rice weed management
currently rely on the application of integrated crop management
practises based on combination of herbicides with appropriate
agronomic practises, such as tillage, soil levelling, water
management, fertilization, variety choice. Several research
projects are also addressing these issues by developing 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 and Tabacchi, 2002). The
use of these varieties combined with prophylactic measures will be
a sound strategy to prevent damage or their spreading to rice.
Lodging resistance has been a key target trait to rise yield
potential and is associated with many component traits such as
plant height, stem strength, thickness, etc. Lodging-resistant rice
cultivars usually show slow grain filling when nitrogen is applied
in large amounts.
Reduced or variable milling yield, grain fissuring, grain
shedding and non-contemporaneous maturity are other important
issues that can affect rice productivity. Most of these problems
are also related to other agronomic constraints, such as cold
temperature and lodging, but are sometimes closely linked to the
genetic features of the rice varieties.
Table 1 Rice area (ha) and yield (tons/ha) in 2005 in
Europe and other main Mediterranean countries (Food and Agriculture
Organisation, 2007).Tableau 1. Zones à riz (hectares) et production
(tonnes/ha) en 2005 en Europe et dans les autres principaux pays
méditerranéens (Food and Agriculture Organisation, 2007).
|
Country
|
Area (ha x 1000)
|
Yield (tons/ha)
|
|
EU countries
|
|
Italy
|
224.0
|
6.17
|
|
Spain
|
117.0
|
7.23
|
|
Portugal
|
25.0
|
4.80
|
|
Greece
|
24.0
|
7.25
|
|
France
|
18.0
|
5.72
|
|
Hungary
|
2.8
|
3.41
|
|
Romania
|
1.2
|
4.18
|
|
Total1 – Weighted mean2
|
412.01
|
6.402
|
|
Other countries (non-EU and Mediterranean)
|
|
Egypt
|
680.0
|
9.80
|
|
Russian Federation
|
145.0
|
4.50
|
|
Turkey
|
80.0
|
5.25
|
|
Ukraine
|
18.0
|
4.45
|
Rice farm organisation and production cost
The number of rice farms dramatically diminished in the last
25 years in all European countries. In Italy, for instance,
the total number of farm decreased to one half in Italy and to one
fifth in Valencia, Spain. In the same period the mean surface per
farm showed an increase roughly proportional to the reduction of
the number of farms (from 20 to 47 ha in Italy and from 1.9 to
4.7 in the Valencia area) The mechanization of roughly all
operations of rice cultivation and the spread of monoculture led to
the increase of the average farm dimensions. This trend is still
continuing, driven by the reduction of the crop profitability, the
increase of the working capacity per ha and the cost of the
machinery (Finassi and Ferrero, 2004).
Such a result was achieved by adopting a particularly high level
of mechanization; in farms with more than 30 ha there is a
tractor every 12 ha and a combine harvester every
59.47 ha. Use of large combines, with a great working
capacity, allowed to reduce the harvest period, but imposed to
adapt the drying capacity in order to manage to carry out drying of
the daily harvested rice. The harvesting time was considerably
reduced, from 35-40 days in the 1950s to the current
20 days.
The cost of rice production in the European Union is generally
much higher than that in most Asian countries. The high production
costs are largely due to the high expenses related to water,
fertilizers, crop protection products, seed, machinery, custom
application, fuel and labour. The cost of production in Europe is
about 280-320 euros/ton (AIDAF-VC/BI, 2003). The return from
rice production showed a sharp reduction in the last 10 years.
Since 1995 international rice prices started a marked declining
process, while fertilizers, seed, crop protection products, custom
application, fuel and labour started to have a significant
increase. Since that time, in fact, the producer price of rice
reduced in five years by about 50% or more in most rice producing
countries (table 2). Starting from 2003
till 2006 the rice market has shown a trend to a recovery of the
prices.
Table 2 Producer price evolution of paddy rice from
1995 to 2003 (USD/ton) (Food and Agriculture Organisation,
2007).Tableau 2. Évolution du prix du riz paddy chez le producteur
de 1995 à 2003 (dollars US/tonne), (Food and Agriculture
Organisation, 2007).
|
Country
|
1995
|
2000
|
2003
|
|
Italy
|
477
|
255
|
250
|
|
Spain
|
479
|
252
|
310
|
|
France
|
564
|
323
|
303
|
|
Egypt
|
207
|
167
|
169
|
|
USA
|
202
|
124
|
160
|
|
Brazil
|
193
|
124
|
92
|
|
Thailand
|
165
|
119
|
122
|
|
India
|
150
|
132
|
121
|
Rice consumption and market
Rice is not the staple food for most of the European population;
nevertheless, rice consumption in the continent has increased in
the last years due to immigration and diversification of the diet
of the Europeans.
In the last two decades rice consumption has significantly
increased in all European countries either rice producers (Southern
Europe) or non-rice producers (Northern Europe). It is presumable
that this trend will continue in the next years particularly in
northern European countries (CEC, 2002).
In 2003 milled rice consumption ranged from 5.4 to
8.8 kg/capita/year, except in Portugal were individual
consumption was 17.8 kg/capita/year) (table
3). Rice consumption showed in the last two decades a
remarkable increase in European importing (non-rice producing)
countries too, where once rice used to be considered as a curious
food or a luxury product. At present there are no significant
differences in consumption patterns between rice producing regions
and rice importing regions of Europe. In importing countries rice
is now of interest for diversifying conventional diets and its
consumption corresponds to a lower potato and cooked vegetable
consumption.
In Southern European countries about 80% of the consumed rice
belongs to japonica varieties (mainly medium and long A type)
and 20% to indica varieties. Very often local and “specialty”
varieties are gaining a significant importance for small and medium
farms in local markets. For example, in Italy varieties like
“Carnaroli” and “Vialone nano” have a good appreciation on local
markets, also thanks to the promotion of their quality, through the
attribution of APO (Appellation of Protected Origin) and the direct
selling of rice by rice growers, who directly process their own
rice production in the farm with small rice milling plants.
In Northern Europe long-grain varieties (long B type) are
commonly preferred. In the United Kingdom and Scandinavian
countries, for example, rice consumption include 85% of indica
types which are mainly imported from the USA, Thailand, India, and
Pakistan. To meet this demand a subsidy was granted the European
Community in the late 1980s to encourage a larger production of
long grain varieties in the European countries (Yap, 1997). All the
varieties which were introduced are suited to temperate climatic
conditions even if they are sometimes damaged by the low night
temperatures, which occur particularly during the flowering period
(Ferrero and Tabacchi, 2002).
Demand for scented rice varieties (Basmati-type). has shown a
significant increase since the early 1990s, primarily in the UK and
other European countries, because of a growing presence of Asiatic
communities (Faure and Mazaud, 1996). It seems reasonable to expect
a further increase in aromatic rice consumption in the years to
come, throughout Europe, 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. The increase of
consumption Basmati-type varieties has also been favoured by a
significant reduction of the import duties.
The enlargement of the EU resulted in a remarkable market
increase of the rice grown in the area (Chataigner and Salmon,
1996). In 2006, the additional consumption due to the 10 new
countries which entered the EU was about 250,000 tons, mostly
from indica-type varieties, equivalent to about 10% of the total
European production.
Since 1995, imports from third countries increased by about 30%,
as a consequence of the Uruguay Round agreements.
Market liberalization for rice will be applied starting from
2009. Tariff reductions will be phased in with a 20% cut in 2006,
50% in 2007 and 80% in 2008. In the meantime a duty-free quota,
based on previous exports to the EU, has been established, with an
increase by 15% each year until 2009, when all tariffs and quotas
will be removed.
On 2003, EU Agriculture Ministers agreed on fundamental reforms
to Common Agricultural Policy (CAP). Most relevant reform is the
break in the link between subsidies and production. The primary
aspects of CAP reform concerning rice are aimed at reducing the
intervention price by 50%, and limiting the amount to
75,000 tons per year. These reductions are compensated by a
subsidy devoted in part to environmental protection.
Table 3 Consumption of milled rice in European
countries (kg/capita/year) (Food and Agriculture Organisation,
2006).Tableau 3. Consommation de riz usiné dans les pays européens
(kg/personne/an), (Food and Agriculture Organisation, 2006).
|
Country
|
1990 (kg/capita/year)
|
2004 (kg/capita/year)
|
|
EU rice producing countries
|
|
France
|
4.1
|
5.4
|
|
Italy
|
5.7
|
6.0
|
|
Greece
|
6.1
|
8.8
|
|
Portugal
|
15.7
|
17.8
|
|
Spain
|
6.2
|
7.1
|
|
Romania
|
4.0
|
6.5
|
|
Hungary
|
7.3
|
7.2
|
|
Weighted meana
|
6.0
|
6.4
|
|
EU non-rice producing countries
|
|
Germany
|
3.4
|
5.9
|
|
UK
|
3.7
|
4.3
|
|
Denmark
|
1.8
|
5.1
|
|
Poland
|
2.5
|
2.9
|
|
Weighted meana
|
3.3
|
4.1
|
aConsumption values weighted on the population of each
country.
Rice quality
According to the “Regulation on the common organisation of the
market in rice” (Council regulation No 1785/2003) main
components of rice quality are grain shape, colour and integrity of
the grain. Other important components are milling quality, cooking
and processing behaviour, grain fissuring.
Rice varieties are grouped into different grain type categories
upon three physical parameters: length, width and length and width
ratio (table 4). The physical dimensions
and weight are considered among the first criteria of rice quality
that breeders consider when developing new varieties. Grain shape
is one of the major aspects of rice quality as it is usually
associated with specific cooking characteristics. In most
varieties, cooked long grain rice is usually fluffy and firm, while
medium and short grain rice is soft, moist and sticky in texture.
The demand among consumers in Northern Europe is higher for long
grain rice.
According to the European regulation paddy rice of standard
quality shall be sound and fair marketable, free of odour, with a
wholly milled rice of 63% in whole grains (with a tolerance of 3%
of clipped grains) and a maximum moisture content of 13%. Paddy
should not show abnormal colour (green, chalky, striated, spotted,
stained, yellow, amber).
Grain fissuring may result in important negative effects during
technological processes. 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. Whole
grain 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
pre-cooked 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 4 Grain type categories and other quality
components of paddy rice.Tableau 4. Catégories de grains et autres
qualités des composants du riz paddy.
|
Grain shape
|
Other quality components of paddy rice (%)
|
|
Type
|
|
Length (mm)
|
Length/ Width ratio
|
Chalky grainsa
|
1.5
|
|
|
Grains striated with reda
|
1.0
|
|
Long
|
Long A
|
> 6.0
|
> 2.0 < 3.0
|
Spotted grainsa
|
0.5
|
|
Long B
|
> 6.0
|
≥ 3.0
|
Stained grainsa
|
0.25
|
|
Medium
|
|
> 5.2
|
< 3.0
|
Amber grainsa
|
0.05
|
|
Short
|
|
< 5.2
|
< 2.0
|
Yellow grainsa
|
0.0
|
aPercentage on wholly milled rice.
Options for sustainable rice productions
Rice is a good example of the multi-functionality of European
agriculture in which production of quality food goes together with
rural development and conservation of the environment. Submerged
rice cultivation is fundamental for a sustainable management of the
wet ecosystems (estuaries, river basins, albuferas, etc.) where the
crop is grown. Many European rice fields are located in natural
parks or environmentally protected areas. The future of rice in the
European countries will most likely be related to the development
of new varieties and environmentally and economically sustainable
methods of production which allow to increase rice yield and
quality by improving water and fertilizer efficiency and minimizing
the use of crop protection products. One of the most effective
means of meeting these goals is research. In the last four decades
rice science has made considerable progress. Important advances
have been made for instance by replacing traditional varieties with
new varieties with better traits such as, for instance, dwarf size,
improved nutrients response, shorter growing cycle, tolerance to
pests and diseases.
Further achievements are expected in development of varieties
tolerant to drought and salinity thanks to the recent success in
rice genome mapping.
Most existing high-yielding varieties have a potential yield
that usually exceeds actual yield which is obtained by farmers. The
gap reflects numerous deficiencies in crop management (Van Tran,
2001). In other areas of rice cultivation (e.g. Australia and
Egypt) it has been demonstrated that much of this gap could be
reduced by applying Rice Integrated Crop Management (RICM) systems
(Clampett et al., 2001). The development and dissemination of
RICM systems in Europe could help lower production costs and
minimize environmental impact of agricultural practises (Nguyen,
2002).
The adoption of hybrid rice technology would be another major
step in raising the yield potential (Christou, 1994). Hybrid rice
varieties, which are cultivated on a large scale since many years
in China and are being developed in Egypt, have demonstrated to
provide a yielding advantage of 15-20% over the existing
high-yielding varieties. The adoption of these varieties in the
European countries, however, still need technologies to increase
the F1 yield and lower, consequently, the cost of the hybrid seed.
Promising results with these varieties have already been obtained
in Spain and Italy.
A crucial aspect of the success in rice research is
collaboration among the few scientist working in the European rice
Centres. Sharing the research programmes is a valuable way to
address the issue of the scarce financial resources and take
advantage from the transfer of information and advanced research
methodologies which result in a shortening the time needed to solve
problems.
Numerous research programmes at a national or international
level have been set up throughout Europe. They include main aspect
of rice science from agronomic management to breeding, quality,
environment and market aspects. Several research projects carried
out in Europe and the Mediterranean regions have been fostered by
Medrice, the FAO inter-Regional Cooperative Research Network on
rice in the Mediterranean Climate areas. This organization was
created in 1990, first under the name MedNetRice, to promote
scientific exchanges among rice scientists working in the
Mediterranean areas and in other regions with a Mediterranean
climate. Thanks to the association to the “Centre international des
hautes études agronomiques méditerranéennes” (Ciheam), the network
has published a large number of technical documents, bulletins
(Medoryaze) and proceedings of several seminars and
conferences.
Research institutions from sixteen countries participate at
present in Medrice: Bulgaria, Egypt, France, Greece, Hungary, Iran,
Italy, Morocco, Portugal, Romania, Russian Federation, Spain,
Turkey, the UK, the Ukraine, and Uzbekistan. Some of the important
subjects considered in the collaborative research include
resistance to blast, stemborers and diseases, quality and
competitiveness of European rice, control of red rice, cataloguing
of rice genetic resources in the region.
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