Cultivation

Rice is grown in tropical and subtropical regions. The main rice-producing areas are the Asia, followed by Africa, and South, North and Middle America. By far the largest rice producing countries are China (around 184 million tons in 2005) and India (around 129 million tons in 2005). In Europe, among other countries, rice is cultivated in Italy (around 1.37 million tons in 2005) and Portugal. Worldwide, in 2005, the total harvest was 615 million tons.

Utilisation

Rice (Oryza sativa) as a cereal is:

• cooked
• processed to starch, rice oil, rice flakes, crispies, rice noodles

In Asia, rice is a traditional foodstuff. Rice is the main food source for almost half of the world's population.

Rice is predominantly a foodstuff and only a very small percent is used as animal feed.

Gene technology: aims of research and development

Agronomic traits

Weed control

• Herbicide tolerance against the active ingredients gluphosinate and imidazolinone

Resistance against pathogens

• Fungal resistance against the agent causing rice blast disease

• Virus resistance: in England (UK - Department of International Development), a rice strain resistant to rice yellow mottle virus has been developed. In Zurich, rice plants have been developed that are resistant against tungro virus and different fungi

• Bacterial resistance, also in combination with fungal resistance

Resistance against pests

• Insect resistance: in China several insect-resistant rice strains have been developed and tested in large-scale trial cultivations. One variety is the so-called Bt toxin, which protects plants from pest such as the rice borer. Another variety produces an active substance originating from broad beans that blocks the alimentary system of the pests.
  In addition, in India, many field trials are being undertaken with insect-resistant Bt-rice.

Adaptation to climate and localisation factors

• Drought and salt tolerance: several research projects are concerned with developing new rice strains that can survive with less water and can grow on saline soils. In China, saline-tolerant varieties have already been developed in which a gene from suaeda salsa, a plant that grows well on saline soils, has been inserted. Similar rice strains are also undergoing field trials in Europe, the USA and India.

Quality traits

Enrichment with health-promoting components such as:

• Golden Rice: natural rice only contains little vitamin A. In countries in which rice forms the main food source, deficiency diseases are widespread that can even lead to blindness. Through the use of gene technology it is possible to develop rice with a higher amount of beta-carotene, a precursor of vitamin A as well as a higher iron content. Golden rice, so named because of its yellow colour, is being crossed with locally adapted rice strains and distributed free to small farmers. The concerns involved have largely waived their patent claims. The first field trials with Golden rice were carried out in Louisiana, USA. In the meantime, a British workgroup has developed an improved variant of Golden rice. Through a gene exchange this variant produces notably more beta-carotene. An average serving of this rice can cover half of the daily requirement for a small child.
  

• In the Philippines, a GM rice has been developed that, besides a high vitamin A content, also shows increased iron and zinc levels.

• Formation and storage of vitamin B9 (folic acid) in the rice corns

• In addition, research is being carried out on rice with an increased flavonoidcontent. Flavonoids function as antioxidants, which are regarded as having a health-promoting effect.
  
  

• In Japan, work is underway to develop a hypoallergic strain of rice in which the formation of an allergen (AS-albumin, glutenin) is suppressed.

Modified composition of components

• In other strains of GM rice the starch composition (amylose) or protein content have been changed. Possible purchasers would be the Sake brewers.

Renewable primary products, energy crops

Production of pharmaceutically active substances

• Molecular pharming: Gene-modified rice plants could be used as production systems for active pharmaceutical ingredients. In the USA, a GM rice has been developed that produces lysozyme and lactoferrin in its corns. These substances are normally present in breast milk and protect small children from infections. The active agents have so far only been produced in experimental field trials and can only be used for research and diagnostic purposes.

• GM rice producing alpha-amylase. Amylase is used to break down starch, e.g. to obtain bioethanol from starch-containing plants.

Plant development

• Yield increases

• Improved ability to take up nitrogen. In the USA a GM rice has been developed that through insertion of a barley gene is able to take up more nitrogen from the soil. This should lead not only to a reduction of the costs for fertiliser but also help reduce the greenhouse effect. Through the intensive use of nitrogen fertilisers in rice cultivation, significant amounts of the greenhouse gas nitrogen oxide is released into the atmosphere.

Land reclamation

• Phytoremediation of soils contaminated with heavy metals: the plants are modified so that they can grow on these soils and take up the heavy metals into the biomass.

Field trials with GM rice

Utilisation of GM rice