1. What is Biofortification?
2. Is Biofortification Cost-Effective?
3. Is Biofortification Sustainable?
4. Does Biofortification Require Genetic Engineering?
5. Are You Planning on Disseminating Transgenics as Part of HarvestPlus?
6. Do Biofortified Foods Require a Change in Consumer Behavior?
7. How Soon Will Biofortified Crops be Available?
8. How Will Biofortification Improve Agronomic Properties of Crops?
9. Can Biofortified Crops Reduce Soil Fertility?
1. What is Biofortification?
Biofortification is the process of breeding food crops that are rich in bioavailable micronutrients, such as vitamin A, zinc, and iron. These crops are “biofortified” by loading higher levels of minerals and vitamins in their seeds and roots during growth. Through biofortification, scientists can provide farmers with crop varieties that provide essential micronutrients and can naturally reduce anemia, cognitive impairment, and other malnutrition-related health problems that affect billions of people.
2. Is Biofortification Cost-Effective?
Unlike the continual financial outlays required for supplementation and fortification programs, a one-time investment in breeding-based solutions can yield biofortified crops for farmers to grow around the world for years to come. It is this multiplier aspect of biofortification across time and distance that makes it so cost-effective in reducing malnutrition.
3. Is Biofortification Sustainable?
Biofortifed crops developed through HarvestPlus are an international public good that will be made freely available to any national agricultural research programs who wants to grow them. While government attention to malnutrition may fade, and international funding for micronutrient interventions may be substantially reduced, nutritionally improved biofortified varieties can continue to be grown and consumed year after year to reduce malnutrition in entire populations. Recurrent costs required for monitoring and maintaining these traits in crops will be far lower than the initial costs of developing biofortified crops.
4. Does Biofortification Require Genetic Engineering?
No. In fact most of the work being done by HarvestPlus to biofortify staple food crops relies on traditional plant breeding techniques to increase the nutritional quality of staple foods. Seed and germplasm banks throughout the world are evaluated for varieties of staple food crops that have naturally occurring higher levels of micronutrients in their seeds. These varieties are then crossed with modern high yielding varieties in an attempt to breed new naturally biofortified varieties that perform well in the field, produce high yields, and that are also more nutritious. However, those essential nutrients that cannot be bred into key food staples through conventional plant breeding methods may require transgenic breeding approaches to provide enough nutrients to significantly improve human nutrition.
5. Are You Planning on Disseminating Transgenics as Part of HarvestPlus?
HarvestPlus is conducting preliminary research to determine what role transgenics can play in breeding biofortified crops. All crops developed by HarvestPlus are public goods and will be given over to countries upon request. It is the national agricultural research programs in developing countries that will make dissemination decisions. Furthermore, as policy, HarvestPlus will not distribute GMOs ever developed under its auspices to any country that does not have biosafety regulatory systems in place or does not wish to adopt transgenic varieties.
6. Do Biofortified Foods Require a Change in Consumer Behavior?
Mineral micronutrients make up a tiny fraction of the physical mass of a seed, for example, only 5 to 10 parts per million in milled rice. Whether such small amounts will alter the appearance, taste, texture, or cooking quality of foods is being investigated. In the case of iron and zinc, increased levels of nutrients may not be noticeable, requiring no special intervention or marketing campaigns. This would be analogous to the practice of adding iodine to salt or fluoride to drinking water.
In contrast, higher levels of beta-carotene (converted in the body to Vitamin A) will often turn the color of grain, flours and roots/tubers from preferred white or light yellow colors to dark yellow and orange colors. Nutrition education programs will be needed to encourage malnourished populations to switch to more nutritious varieties and recognize the color changes as a food quality trait.
7. How Soon Will Biofortified Crops be Available?
In its first four years, HarvestPlus has proven that crops can indeed be bred to contain higher levels of micronutrients. However, it takes many years to breed and test new varieties of crops that have all the required traits to satisfy both farmer and consumer needs. Biofortified crops must also be field tested to ensure that they maintain these traits in different growing environments and can provide enough micronutrients to improve the nutritional status of consumers. More than 200 scientists, researchers, and marketing and behavioral change specialists around the world are working together to develop and test HarvestPlus crops. It is anticipated that as soon as 2012, several varieties of micronutrient-rich staple crops should be ready for distribution in the developing world where micronutrient malnutrition is prevalent.
8. How Will Biofortification Improve Agronomic Properties of Crops?
Adequate nutrition is as important to plant health as it is in human health. Micronutrient deficiency in plants greatly increases their susceptibility to diseases, especially fungal root diseases of the major food crops. Efficiency in the uptake of mineral micronutrients from the soil is associated with disease resistance in plants, which leads to decreased use of pesticides and fungicides. Breeding for micronutrient efficiency can confer resistance to root diseases that had previously been unattainable.
Micronutrient-efficient varieties grow deeper roots in mineral-deficient soils and are better at tapping subsoil water and minerals. When topsoil dries, roots in the dry soil zone (which are the easiest to fertilize) are largely deactivated and the plant must rely on deeper roots for further nutrition. Roots of plant genotypes that are efficient in mobilizing surrounding external minerals not only are more disease resistant, but are better able to penetrate deficient subsoils and so make use of the moisture and minerals contained in subsoils. This reduces the need for fertilizers and irrigation. Plants with deeper root systems are also more drought resistant.
Micronutrient-dense seeds are associated with greater seedling vigor, which, in turn, is associated with higher plant yield A significant percentage of the soils in which staple foods are grown are “deficient” in these trace minerals, which has kept crop yields low. In general, these soils, in fact, contain adequate amounts of trace minerals, enough for hundreds or thousands of crops. However, because of chemical binding to other compounds, these trace minerals are “unavailable” to staple crop varieties presently used.
In addition, the HarvestZinc Fertilizer Project is using agronomic biofortification, which is the application of zinc-enriched fertilizers, to improve the zinc concentration of cereal crops. Agronomic biofortification further encourages and ensures plants to produce zinc-dense seed and also contributes to yield.
9. Can Biofortified Crops Reduce Soil Fertility?
A soil is said to be deficient in a given nutrient when the addition of fertilizer produces better growth—even though the amount of nutrient in the fertilizer added may be small compared with the total amount of the nutrient in the soil. This seeming paradox can occur when only a small part of the nutrient in the soil is available to plants, owing, for example, to the chemical properties of the soil.
Alternatively, the view can be taken that there is a genetic deficiency in the plant rather than a deficiency in the soil. Rather than adapting the soil to the plant, breeding can adapt the plant to the soil.
The table below gives an analysis of both total and extractable micronutrients in one trace element-deficient sandy soil in comparison with the nutrients removed in the grain of an average crop grown on that soil. The picture presented for nitrogen is quite different from that for trace minerals. Few soils of the world can sustain high yields for long periods without additional supplies of nitrogen, either by rotation of the crop with nitrogen-fixing legumes or from mineral fertilizer additions. Thus, it is pointless to breed for greater tolerance to nitrogen-deficient soils. Trace minerals are present in much greater concentrations (compared with plant needs) even in a nutrient-impoverished soil such as that below. It is logical, then, to concentrate breeding efforts on these elements with low requirements or low availability, but large reserves in the soil.
Nutrient balances in a wheat-growing soil of South Australia
Source: Graham 1978
