Types and varieties of coffee

The chromosome base number of the genus Coffea is Xanth11, except for the Arabian species (Coffea arabica L.) Because 2n=44 belongs to heterologous four-bit in vitro, the rest are 2n=22. At present, people have done the most research, the ones that have been domesticated and cultivated in a large area are only the small-grain species (Arabian species) and medium-grain species (C. canephora, also known as Robasta Robusta), while the large-grain species (C. liberica) and C. dewevrei) are cultivated in a small amount in a few countries.

Main cultivated species and varieties of coffee

1. Arabian species (Coffea arabica L.)

It is called small seed in our country. Native to Africa, southwestern Ethiopia and southeastern Sudan, between 1000 and 2000m above sea level, after artificial introduction and cultivation, it has spread all over the tropical regions of the world and is the main cultivated species in the world. The planting area and yield account for more than 80% and 82% of the world's total area and yield, respectively. Distributed at high elevations (1300m) between 28 degrees north and 38 degrees south. The main producing area is Latin America, of which Brazil is the most, followed by Colombia, and there is a large area of cultivation in East and West Africa. China's Yunnan, Guangxi, Fujian, western Guangdong, Hainan and other provinces and regions have been successfully introduced and cultivated. In China, small-grain species are mainly cultivated except Hainan, and coffee cultivated in Yunnan is also small-grain species.

Arabian coffee (small seed) is an evergreen shrub with a relatively small plant, 4ml 5 m high and branches slender (0.7 mi 0.85 m); the leaves are small and pointed, long oval, hard, leathery, with fine and obvious corrugated edges; the terminal buds are green or bronzed, so Yunnan is called "green top coffee" and "red top coffee". The number of results per node is generally 12 color 20, more than 25. When the branches have more fruit nodes, the fruit is smaller, the pulp is sweeter, the seed coat is thicker, and it is easy to separate from the seeds. The ratio of fresh fruit to dried beans (hereinafter referred to as fresh-dry ratio) is about 4.5-5:1, the seeds are lighter, 4000 grains per kilogram of dried beans, but the number of dried beans per kilogram is different in different planting areas. Under the condition of good management, its yield is not less than that of medium-grain species. It is more cold-tolerant and drought-tolerant, and the general varieties are susceptible to leaf rust and vulnerable to longicorn beetles. The natural life span can be up to 100 years, but the economic life is about 25 years. The product has a mellow smell and good drinking quality.

Because of its rich variation types, this species has been selected and bred the following varieties or varieties with cultivation value after artificial selection.

Tiebika variety (C arabica var. Typica Cramer) is native to Ethiopia and southeastern Sudan and is widely cultivated in the Western Hemisphere. There are many results, large berries, early ripening, high yield, strong plants, conical mature trees, bronzed young leaves, narrow leaves, not tolerant to strong light, and easy to develop withered branches.

Bourbon variety (C arabica var. Bourbon Choussy), native to Burundi, is a variety of Arabica coffee second only to Tibika in cultivated area. The lateral branches have dense internodes, many fruits, high yield, small berries and late ripening. The tender leaves are light green, light-resistant and suitable for high-altitude, unshaded environment. It is highly productive in Brazil, so it has gradually replaced Tibika.

Kaddura variety (C arabica var. Caturra KMG) A single gene mutant of the Bourbon variety, originated in Brazil. Is a high-yielding variety, the plant tree type is short, only 1.2 meters high, without shade. But it needs fertile land and meticulous pruning, and its disease resistance is poor.

The cultivated species of Mondonovo (Mundo Novo cultivar), which originated in Brazil, is a high-yielding variety selected from the natural hybrid offspring of the high-product lines of Bobang and Tibica. Its yield is higher than that of Bobang and Tibica, but the fruit is smaller, and it is often not full or sterile.

Kent, which originated from India, is a high-yielding variety found by L. D. Kent in his coffee garden in 1911. It shows vigorous growth and is resistant to rust and green insects. It has been widely cultivated in India.

S288 originated in India and was bred by self-breeding of S26, a natural hybrid of small-grain and large-grain coffee and Kent. This variety has the ability to resist race Ⅱ of coffee rust. It has been widely popularized in China, but it is not recommended because of its poor adaptability.

SLN9 is a hybrid of Ethiopian wild small grain species and rust-resistant Timon Island hybrids. It shows strong rust resistance, drought tolerance and high yield.

K7 the main commercial cultivated species in Kenya, derived from Kent, is suitable for growing at low and middle elevations, is not resistant to rust, but resistant to coffee blight.

Hibrido de Timor, which originated from Timor Island, is a natural hybrid of small and medium seeds. It is an antigen variety with a stable resistance gene to coffee berry disease and leaf rust.

SL28 is a major commercial cultivated species in Kenya, grown mainly at middle elevations and of good quality but not resistant to rust.

SL34 the main commercial cultivated species of Kenya, mainly grown in areas with high and medium elevations and heavy rainfall, is not resistant to rust but of good quality.

Kaddura (Caturra) Bobang variety bred in Brazil is not rust-resistant, dwarf and high-yielding, and its yield is higher than Tibica. It has been planted on a large scale in Brazil and Colombia, but now there are few new plants.

Ruyilu-11 (Ruiau-11) SL28 and SL34 of Kenya Coffee Research Institute were bred by single cross or double cross with coffee bitter rot (CBD) resistant variety Rume sudan and rust resistant dwarf production variety. It has wide adaptability and has been widely planted in Kenya.

two。 Robasta species (C. robusta)

Also known as C.canephora species, commonly known as medium-grain species, originated in the African Congo tropical rain forest, the cultivated area is second only to small-grain species, distributed in the low altitude (900m) between 10 degrees south and north latitudes. The main producing areas are southeastern countries, India and central and eastern Africa. China is mainly cultivated in Hainan Province.

This kind of evergreen small tree has a medium plant height of 5 Mel 8 meters, a sturdy trunk, a late cork of branches, slender and soft branches, and drooping after fruiting. The leaf is long and large, oval, wrinkled soft and thin, leaf margin ripple is large and obvious, leaf vein is dense. Leaf blade glossy, apex pointed. There are many branches and 30 branches, and there are 30 fruits in a single node. The shape of the fruit varies from type to type, oblate or oval, fuchsia and crimson when ripe. The pericarp, pulp and seed coat are thin. The ratio of fresh to dry is about 3.5-5.1. The berry juice is less, and the seed coat and pericarp are not easy to separate. There is a big difference in seeds, 2600Mel 5600 seeds per kilogram of dried beans. Do not tolerate strong light, need shade, shallow roots are not resistant to drought, need higher temperature, the cold resistance is the weakest, but the rust resistance is the strongest and less harmed by longicorn beetles, and the yield is higher. The product has a strong and fragrant taste and strong irritation.

The main cultivated varieties of this species are (Quillon), Ugandan species (Uganda) and 10 medium-grain clones 107,126,182,197,461,477,503,505,149,400 have been bred in Codiva in recent years. Its 149 and 400 are more dry.

3. Liberian species (C. liberica)

Also known as large seed. Originated in Liberia, Africa, the cultivation area of the world is relatively small, distributed in Liberia, Malaysia, India, Indonesia and other countries. It is suitable for planting in low altitude areas. For evergreen trees, the plant is tall, more than 10 meters high, the main branches grow diagonally upward at a sharp angle with the trunk, the branches are thick and hard, and the branches are corked the fastest. The leaf is large, oval or long oval, leathery, thick, hard and shiny, and the ripple of the leaf margin is very small. The veins are sparse. There are generally 6 branches bearing less fruit, with large fruit, sparse planting and low yield per unit area, but high yield per plant. The fruit is large, oblong, scarlet when ripe, and the skin and flesh are hard and thick. The ratio of fresh to dry is 7-10:1, 1300 dried beans per kilogram, and the seed shell is thick and hard. The main root is deep, drought-resistant, wind-resistant, light-resistant, adult trees do not need shade, moderate cold resistance, the most likely to be infected with leaf rust. The product has a strong bitter taste, strong irritation and poor drinking quality, but it can be mixed with other coffee to improve drinking quality.

The main varieties are Ethel (C. excelsa). In 1905, it was found in the Chari River in the Congo of Africa, so it is also known as the Charlie species.