(planted in field collections), in vitro (as plantlets in test tubes within a controlled environment), and by cryopreservation (meristems conserved in liquid nitrogen at −196 °C). At the Honduran Foundation for Agricultural Research there were attempts to exploit the rare cases of seed production to create disease-resistant varieties; 30,000 commercial banana plants were hand-pollinated with pollen from wild fertile Asian fruit, producing 400 tonnes, which contained about fifteen seeds, of which four or five germinated." Further breeding with wild bananas yielded a new seedless variety resistant to both black Sigatoka and Panama disease. Genes from wild banana species are conserved as DNA and as cryopreserved pollen and banana seeds from wild species are also conserved, although less commonly, as they are difficult to regenerate. In addition, bananas and their crop wild relatives are conserved in situ (in wild natural habitats where they evolved and continue to do so). Diversity is also conserved in farmers' fields where continuous cultivation, adaptation and improvement of cultivars is often carried out by small-scale farmers growing traditional local cultivars. Nutrition Raw bananas (not including the peel) are 75% water, 23% carbohydrates, 1% protein, and contain negligible fat. A 100-gram reference serving supplies 89 Calories, 31% of the US recommended Daily Value (DV) of vitamin B6, and moderate amounts of vitamin C, manganese and dietary fiber, with no other micronutrients in significant content (see table). Ripe dessert bananas are soft, bland, and easily digestible, making them ideal for those with gastrointestinal distress. Therefore bananas are part of the BRAT diet. Potassium Although bananas are commonly thought to contain exceptional potassium content, their actual potassium content is not high per typical food serving, having only 8% of the US recommended Daily Value for potassium (considered a low level of the DV, see nutrition table), and their potassium-content ranking among fruits, vegetables, legumes, and many other foods is relatively moderate. Foods with higher potassium content than raw dessert bananas (326 mg per 100 g) include ground flaxseed (793 mg per 100 g), dry-roasted almonds (684 mg per 100 g), peanut butter (654 mg per 100 g), raw baby spinach (582 mg per 100 g), white button mushrooms (393 mg per 100 g), and whole grain oats (350 mg per 100 g). Raw yellow plantains contain 487 mg potassium per 100 g. Dehydrated dessert bananas (banana powder) contain 1490 mg potassium per 100 g. Allergen Individuals with a latex