Some historians state that citrus is originally from east Asia, from the region that include India, China, Bhutan, Myanmar (Burma) and Malaysia today.

Citrus was described for the first time in Chinese literature in approximately 2000 B.C.

The path of oranges around the world is known only approximately. According to most researchers, it was taken from Asia to North Africa and then to the southern part of Europe, where it would have arrived in the Middle Ages. From Europe it was carried to the Americas at the time of the discoveries, circa 1500.

Oranges spread worldwide and suffered mutations giving origin to new varieties. During the greater part of this period, citriculture was left to its own fate - seed cultivation randomly modified taste, aroma, color and size of the oranges.

Researches and experiments to improve orange varieties began in the 19^th century in Europe, after the dissemination of Mendel's and Darwin's theories. Before the beginning of the 20^th century the U.S. was already leading the technical efforts in this area. All studies were always directed to improve fruit aspect, size and taste, and to improve it genetically to obtain trees more resistant to diseases and climatic variations.

Currently, the more productive groves, resulting from structured citricultures are in tropical and sub-tropical climate regions, especially in Brazil, the United States, Spain, Mediterranean countries, Mexico, China and South Africa.

Forty to fifty centuries after its assumed 'domestication', the highest volume of orange production is in the Americas, where the fruit was introduced 500 years ago. The State of São Paulo in Brazil and the State of Florida in the United States are the main producing regions of the world.

From 1530 onwards, the Portuguese colonial government decided to effectively colonize Brazilian land, dividing the territory of the colony among a dozen of men it confided in and who had to populate and produce sugar in areas called captaincies.

With the new inhabitants' arrival, the first fruit trees appeared and from then onwards, i.e., 1530/40, that historians and scholars usually place the beginning of citriculture in Brazil. Documents and books that describe Brazil in the beginning of its colonization mention the excellent climatic adaptation of citrus trees to the Brazilian coast.

Therefore, Brazilian citriculture is only 40 years younger than Brazil itself. The first records of orange and lemon plantations were found in the Capitania de São Vicente.

Nursery trees and techniques were brought from Spain by Portuguese colonizers, to create a supply of vitamin C, an antidote to scurvy, which killed most of the crews during the time of the discoveries and of the colonization of Latin America.

During the first half of the 19^th century, Brazil received European researchers' special attention and great interest. At that time, many studies and books on Brazil were produced. Many were travelers that mentioned the existence of wild oranges in the Brazilian backlands, which lead many to believe orange was a native fruit. Actually, its good adaptation to the Brazilian climate and soil produced a typical variety, internationally known: the "Bahia" or "navel" orange, which appeared about 1800.

It's not possible to establish the precise date, nor who was responsible, but it is certain that it was after the appearance of the Bahia orange that citrus production became a part of Brazilian agriculture. In that initial phase, in which men work with a spontaneous creation of nature, the evolution of citrus production is slow and easy, but the seedlings start to be disputed all over the country, and begin to spread little by little, in a scale of considerable size.

In 1873, taking advantage of the North American diplomatic services established in Brazil, technicians specialized in citrus production in Riverside, California, received three seedlings of Bahia orange, from which came the seedlings that would later be spread all over the United States and other parts of the world with the name of Washington Navel. Therefore, the citrus exchange between the two countries is over a century old, and the Bahia orange was a fundamental base for that exchange.

During the 19^th centurycitrus production in Brazil had no commercial importance. This preliminary period of evolution coincided with deep changes in the country. Between 1822 and 1889 Brazil declared its independence and became a Republic. In the economy, sugar fell and coffee grew in importance; in the labor front, the slaves were freed and their places were taken by immigrants.

Coffee began to spread to the interior of the state of São Paulo, and orange followed close by, taking space as an accessory culture. Oranges were produced in the farms for internal consumption, and whatever was leftover was sold in the cities. At the beginning of the twentieth century the Brazilian citrus production began to take its place as an "agricultural option". As a subsidy to farmers, the State Government of São Paulo began the distribution of seedlings. Later on, with the crisis in the coffee markets, citrus production started to take more space.

During the 1920s, a still incipient Brazilian citriculture was formed following foreign manuals - Brazilians who were interested in oranges used information based on the United States experience. The most important book for Brazilian producers, "The Cultivation of Citrus Fruits", by Harold Hume, published in the U.S.A. in 1926, was only translated into Portuguese in 1952.

However, the pure and simple transposition of U.S. standards did not automatically work. Oranges were a very popular product, but few producers had a good grasp of their cultivation methods; they were exported regularly, but nobody new their total production, planted area or yield. Brazil began to import, together with the technologies the technicians of other countries, and began developing, with the help of schools and institutes that were founded in the country, its own procedures and standards.

It was only in 1927 that Brazil began exporting citrus on a regular basis. From the 1930s onwards, orange became part of a movement to diversify the Brazilian exports agenda, and in 1939, orange became one of its ten most important export products.

In 1932, the orange business had expanded in such a way that other sectors were turning their attention to it. Naturally, the orange adventure gained more consistency with the downfall of coffee plantations in 1929. At that time, the largest producing and exporting movement was already concentrated in the State of São Paulo.

Growers and exporters had to work fast to place their production in the internal market. Many failed attempts were made at producing orange juice, and the production of essential oil was the way out, which came to be temporarily considered as the salvation of citriculture in Brazil.

The sharp fall in exports to Europe gave origin to a crisis that practically destroyed the Brazilian citrus production - not only because of the lack of buyers, but also because of diseases that spread as a result of the neglect of the groves.

Besides the increase in the presence of known diseases, this neglect of the groves favored the spread of a disease which was unknown at the time, called "tristeza" (sadness), which led to the progressive death of the trees. Caused by a virus, this disease destroyed about 80% of the citrus trees that country had at the time.

During the war years the technicians of the Agronomic Institute, Biological Institute and of the Luis de Queiroz Agronomic School, worked feverishly to find the cause and put an end to the "tristeza" disease of the groves. Many plantations had to be destroyed ant totally replanted. The definitive solution to the disease was developed only in 1955. This was the first success of the partnership among the researchers and businessman, which later paved the way that promoted the development of the Brazilian citrus industry.

Despite the recovery of the groves and the rebirth of production and exportation, it was also during the 1950's that a new element entered the scene, with deep and lasting effects: the bacteria called Xanthomonas axonopodis pv. citri, the agent of citrus canker. First identified in Asia, this bacteria caused injuries in the fruit, leaves and limbs, and entered Brazil through seedlings illegally brought from Japan.

In order to fight citrus canker the Ministry of Agriculture created the National Campaign to Eradicate Citrus Canker. But the effective eradication of the disease and the promotion of a better sanitary control in the groves of the state of São Paulo came only with the creation in 1977 of Fundecitrus - Fund for Citrus Plant Protection, an entity sponsored by citrus producers and processors.

Fundecitrus work was extremely important in the eradication of citrus canker and the entity works continuously to preserve the largest citriculture complex of the world. It became known worldwide for monitoring pests and diseases, carrying out researches with a totally private budget of more than R$40 million plus occasional funds obtained from the federal government, as well as for its partnerships with universities and research institutes in Brazil and abroad.

The damage was huge and recovery very slow. The shortage of juice caused by the frost transformed Brazil in a promising supplier for the North American and European markets. Small almost experimental processing plants were created, in the São Paulo State hinterland.

Official statistics register some orange juice exports in 1961 and 1962. But for all purposes, the Brazilian citrus industry for export was born in 1963, when Brazil exported over 5,000 tons of juice, invoicing slightly over US$2 million.

Brazil, driven by the export growth and development of its citrus industry is currently the largest orange producer of the world and the state of São Paulo alone is responsible for 70% of orange domestic production and 98% of juice production.

The orange agroindustrial system is a case o success in Brazil. It is a product that meets 50% of international demand and 75% of international transactions, bringing in more than US$1 billion in foreign currencies to Brazil every year, and the center of a productive chain that generates a GDP equivalent to US$5 billion. The sector is responsible for approximately 400,000 direct jobs and it is an essential economic activity for 322 municipalities of the State of Sao Paulo and 11 municipalities of the State of Minas Gerais - i.e., the largest citriculture of the world.

After expanding quickly, the citriculture complex suffered a reduction to 700,000 hectares and 180 million trees in 2000. Despite this 12% drop in planted areas and 11% reduction in the number of planted trees, production increased by 30%, which demonstrates the Brazilian productive sector's significant increment in productivity and capacity.