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Evaluating the wild and cultivated diversity |
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The main justification for investing in conserving banana diversity in field and in vitro genebanks is that it will be used, if not today, then one day. But for germplasm to be useful to the widest range of users possible, it is essential to understand its many attributes (botanical, agronomic, nutritional, resistance to biotic and abiotic stresses, processing quality, etc).
The importance of having data on cultivars is illustrated by the story of the Karat banana in the Pacific Island of Pohnpei, Micronesia. The cultivar was languishing in neglect in a few restricted sites for several decades until analysis was carried out on its micronutrient content. The fruit has such high levels of provitamin A carotenoids that it has the potential to play a key role in improving the nutritional status of children in the developing world. Karat has since become an emblem for Pohnpei.
Unfortunately, too little is known about the vast majority of banana cultivars, especially rarer varieties that are less marketable or restricted to particular indigenous groups or geographical areas which are coming under increasing global influences. These trends exacerbate the underutilization of diversity.
Even less is known about wild species, which represent the richest source of genetic diversity in the gene pool and, given their exposure to evolutionary forces imposed by pests and diseases or climate and environmental changes, are likely to harbour valuable traits conveying resistance to biotic and abiotic stresses.
Screening for nutritional value
Bioversity has initiated a process of large-scale screening of traditional cultivars and processed dishes for micronutrients—carotenoids, iron and zinc—as part of the HarvestPlus Challenge Programme. Under this initiative, cultivars are being sorted according to the 'orangeness' of the fruit pulp, and further analysed by spectrophotometry and high performance liquid chromotography by partners at the Centre africain de recherches sur bananiers et plantains and the International Institute of Tropical Agriculture in Cameroon, and the Katholieke Universiteit Leuven in Belgium.
Preliminary results suggest that several popular cultivars consumed in Cameroon have more than ten times the carotenoids content of Cavendish dessert bananas. Consuming around two orange-fleshed plantain fruit a day has the potential of providing an adult’s recommended vitamin A requirement. More studies are needed to determine if these carotenoids are retained after cooking or processing, and are actually absorbed and transformed into vitamin A by the consumer.
Bioversity continues to seek funds and opportunities for characterizing and evaluating a broad range of germplasm for performance and traits as part of the ongoing efforts to rationalize and add value to conservation efforts. |
Grants
• Addressing micronutrient deficiencies in West and Central Africa through Musa-based foods |
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What we do 