Cavendish banana subgroup

' Cavendish ' is the name of today's world economically important banana variety. It is named after William Cavendish, the sixth Duke of Devonshire, the bananas already planted around 1830, in his garden at Chatsworth House from China. Almost all bananas traded worldwide are taken today of posts originating from southern China cultivar ' Cavendish ', which was developed in 1953.

Properties

The ' Cavendish' banana supplanted the preferred in the first half of the twentieth century ' Gros Michel ' (also called' Gran Michel ' or Jamaican banana called ) from the world market because it was easier to industrial use. This was due to the lower plant height of shrubs and their relation to storms higher resistance. Since they could be planted more densely standing, doubled with their growing crop yields. They also seemed to be more robust against certain types of fungus that infested the ' Gros Michel ' as a result of cultivation in large plantations: The type of fungus Yellow Sigatoka got one with fungicides in the handle, the Panama disease could not be rectified at the ' Gros Michel '.

' Cavendish ', however, is much more sensitive to the stresses of transportation due to their thinner shell, so this requires a very large expense. It was also found that, despite their insensitivity to the mushrooms that the ' Gros Michel ' afflict today are even more susceptible to fungal infection than were the varieties used earlier already, because now more fungal strains have occurred.

Fungal diseases

The ' Cavendish ' is threatened as the ' Gros Michel ' by two fungal species:

• The Tropical Race 4 ( TR4 ) of Fusarium oxysporum f sp. cubense, the causative agent of Panama disease, since the 1990s, attacks the roots of banana trees. In Indonesia, Malaysia, Australia and other parts of Southeast Asia, many banana plantations have already been destroyed by this fungus. With pesticides could not stop the spread of the fungus. Because of today's travel activity is a risk of its global distribution.

• The perennials in the Caribbean and Central America are, however, threatened in the 1970s, newly emerging Black sigatoka fungus, which is considerably more aggressive than its predecessor, the Yellow Sigatoka. The black Sigatoka is indeed combatted with pesticides, but even he is now developing drug resistance has become so persistent that in some growing areas half of the crop is useless by his attacks.

Since the ' Cavendish' - banana since their cultivation jungfernfrüchtig ( parthenocarpic ) proliferate, so do not by fertilization and seed formation, but vegetatively by the formation of shoots that are genetically identical to the mother plant, they may be natural resistance to the fungus hardly train, because of this extensive genetic mutations would be required.

For this reason, intensive research on the development of genetically modified banana varieties, including variants of the Cavendish that have been enhanced with resistance genes.

In the Honduran Foundation for Agricultural Research ( FHIA ) it is preferable to the way traditional breeding more robust varieties. It achieved initial small successes by crossing wild, fertile bananas. The first of it newly bred bananas are insensitive to the Black Sigatoka and Panama disease, but taste more like apple than after banana. The FHIA -01 ' Goldfinger ' in 1994, patent pending (U.S. Patent PP08983 ) and FHIA -03 'Sweet Heart ' is already grown in Cuba.

But the wild bananas and only regionally limited cultivated forms are at high risk, especially in India.