Heirloom and Open-Pollinated Seeds
Heirloom and open pollinated seeds represent the genetic diversity of earth. Unlike hybrid or other genetically modified varieties heirlooms have not been genetically altered from their original natural state. Genetic diversity, as the name implies, means diversity of genes! Because of genetic modification and modern agricultural methods, we have limited ourselves to growing fewer and fewer varieties of plants, which means the genetic diversity of earth is in danger. Heirloom Seeds saved for generations carry characteristics that are important in the preservation of genetic diversity. They carry the adaptations the plant has made in order to reproduce in its local conditions and resistance to pests and diseases; and this information is needed in order to carry forward natural improvements for future generations.
For years now 5 main seed companies – that control more than 95% of the world seed supply – have been buying up natural seed supplies and taking them off the market. The hybrid and genetically modified seeds sold by these companies are in effect sterile meaning that after one harvest the seed will not produce again, forcing people to return to the company to buy more seed. In addition, these seeds have been tampered with – sometimes across the species divide – making the plants more disease resistant or cold resistant, but in some cases dependent on fertilisers and pesticides to grow. When seeds are bred in controlled conditions they can be weakened making them less hardy or able to adapt to climate extremes or new diseases. But worst of all, when seeds are bred in such a way that the plant cannot reproduce successfully.
Heritage and non-hybrid seeds are open-pollinated, and unlike hybrid F1 varieties, which means that seeds can be saved for future years, developing dynamic crops and adapting to the local ecosystem.
The nutrient content of vegetables is the last thing on the minds of these companies and science has shown that the nutritional value of our vegetables has declined rapidly over the past 50 years since the rise of industrial farming methods.
A 2004 study in Journal of the American College of Nutrition, Changes in USDA Food Composition Data for 43 garden crops compared nutritional analysis of vegetables from 1950 to 1999 and found 6 of 13 nutrients/vitamins significantly reduced, including 6% of protein and 38% of riboflavin. Reductions in calcium, phosphorus, iron and ascorbic acid were also found. It concluded changes in cultivated varieties were the likely reason. The fact that we no longer produce the wide variety of vegetable types that we used to has decreased the gene pool and decreased the nutrient content of our food.
Mother Earth News also reported on evidence compiled by Dr Donald R Davis from the University of Texas in the article “Declining Fruit and Vegetable Nutrient Composition,” HortScience, 2009; who found that:
• In wheat and barley, protein concentrations declined by 30 to 50 percent between the years 1938 and 1990.
• Likewise, a study of 45 corn varieties developed from 1920 to 2001, grown side by side, found that the concentrations of protein, oil and three amino acids have all declined in the newer varieties.
• Six minerals have declined by 22 to 39 percent in 14 widely grown wheat varieties developed over the past 100 years.
• Official U.S. Department of Agriculture (USDA) nutrient data shows that the calcium content of broccoli averaged 12.9 milligrams per gram of dry weight in 1950, but only 4.4 mg/g dry weight in 2003.
All of this evidence has been assembled and rigorously reviewed by Dr. Donald R. Davis, a now (mostly) retired chemist from the University of Texas.
The evidence indicates there are at least two forces at work.
The first is what agriculture researchers call the environmental “dilution effect.” Davis notes that researchers have known since the 1940s that yield increases produced by fertilization, irrigation and other environmental means used in industrial farming tend to decrease the concentrations of minerals in those plants. These techniques give growers higher yields, and consumers get less expensive food. But now it appears there’s a hidden long-term cost — lowered food quality.
For example, a study of phosphorous fertilizer on raspberries found that applying high levels of phosphorus caused the yield to double and concentrations of phosphorus to increase in the plants, but meanwhile levels of eight other minerals declined by 20 to 55 percent!
The other force at work is what Davis calls the "genetic dilution effect" — the decline in nutrient concentration that results when plant breeders develop high-yielding varieties without a primary focus on broad nutrient content. That’s what the studies of wheat, corn and broccoli confirm.
“These studies suggest to me that genetic dilution effects may be common when selective breeding successfully increases crop yield,” Davis says. USDA data indicate that yields have increased an average of 1.8 fold for 24 vegetables and 1.3 fold for six fruits over the past 30 years.
Vegetables and fruits are our richest sources of many vitamins and minerals. The only way to ensure the best nutrient value in your fresh produce is to grow or buy slow-growing heirloom varieties that have been organically grown.
Click here for the
South African heirloom seed repository.