Searching for disease resistant banana variety

In the 80s a disease named black Sigatoka became a great threat to the banana plantations. This fungus is very difficult to control because it affects a number of varieties and it becomes very quickly resistant against pesticides. Together with the Panama disease it forms a great threat for the banana cultivation worldwide. Especially for the smaller traders there had to be something done to make sure that the food security was not compromised. The people saw the need to keep all varieties safe and search for disease resistant bananas. The worlds biggest and most extensive banana collection is in Leuven (Belgium).

The collection in the Laboratorium Tropische Plantenteelt (Laboratory for Tropical plants) is managed by Bioversity International, and consists of about 1400 varieties from around the world. The active collection is preserved in vitro, in test tubes, in a room with light at a temperature of 15 C. From of every variety about 20 plants are kept. However, contaminations and mutations may occur. To avoid this the laboratory in Leuven has come up with a method that the plants are kept in liquid nitrogen at a temperature of -196 °C, which stops the development. "This the safest and most sustainable method and the only one of its kind", advises Ines Van der Houwe of sector biological plant technique.

The laboratory is working to get an as complete collection as possible. "With the present collection we represent a significant part of the biodiversity of the banana, but the real purpose is to develop more," says Ines. She is hoping that in the future she will bring more wild varieties back. "Besides disease resistance we are also looking for bananas that are resistant against drought, because with the climate changing we will need them in the future." This gene bank is part of an organisation with a worldwide network of banana scientists, that has supported the creation of this unique extensive collection.

Each year, samples from the collection of 800 different species are spread worldwide to different research institutes, amongst others to create resistant banana varieties. The material also gets sent to developing countrys for the smaller growers. "The living conditions of the locals have been improved by giving them suitable varieties to offer them food security and a source of income, that is a important focus point of the organization."

In the laboratory, located at the University of Leuven, people are working hard on using genetic modification to create a banana variety which is no longer affected by harmful fungus. Ines indicates that the classic breeding with bananas is very difficult because an edible banana doesn't have any seeds. Through some interventions people are succeeding in producing seeds with the positive features of the cross breeds.

The bananas that are consumed in Europe are mainly the variety Cavendish. Because there is a monoculture the banana disease could become a serious problem for the banana. Now breeding products have been developed that are immune to the sickness, but these plants are, according to Ines, much more use to the local growers. "We're working hard to discover new genes that are resistant, to make sure that even here we still keep eating bananas.