Wheat Belly. William Davis, MD

Чтение книги онлайн.

СКАЧАТЬ I found Elisheva Rogosa. Eli is not only a science teacher but an organic farmer, advocate of sustainable agriculture, and founder of the Heritage Grain Conservancy (www.growseed.org), an organization devoted to preserving ancient food crops and cultivating them using organic principles. After living in the Middle East for ten years and working with the Jordanian, Israeli, and Palestinian GenBank project to collect nearly extinct ancient wheat strains, Eli returned to the United States with seeds descended from the original wheat plants of ancient Egypt and Canaan. She has since devoted herself to cultivating the ancient grains that sustained her ancestors.

      My first contact with Eli began with an exchange of e-mails that resulted from my request for 2 pounds of einkorn wheat grain. She couldn’t stop herself from educating me about her unique crop, which was not just any old wheat grain, after all. Eli described the taste of einkorn bread as “rich, subtle, with more complex flavor,” unlike bread made from modern wheat flour that she believes tastes like cardboard.

      Eli bristles at the suggestion that wheat products might be unhealthy, citing instead the yield-increasing, profit-expanding agricultural practices of the past few decades as the source of the adverse health effects of wheat. She views einkorn and emmer as the solution, restoring the original grasses, grown under organic conditions, to replace modern industrial wheat.

      And so it went, a gradual expansion of the reach of wheat plants with only modest and continual evolutionary selection at work.

      Today einkorn, emmer, and the original wild and cultivated strains of Triticum aestivum have been replaced by thousands of modern human-bred offspring of Triticum aestivum, as well as Triticum durum (pasta) and Triticum compactum (yielding very fine flours used to make cupcakes and other products). To find einkorn or emmer today, you’d have to look for the limited wild collections or modest human plantings scattered around the Middle East, southern France, northern Italy, or Eli Rogosa’s farm. Courtesy of modern human-managed hybridizations and other genetic manipulations, Triticum species of today are thousands of genes apart from the original einkorn wheat that grew naturally, farther apart than you are from the primates hanging from trees in the zoo.

      Modern Triticum wheat is the product of breeding to generate greater yield and characteristics such as disease, drought, and heat resistance. In fact, wheat has been modified by humans to such a degree that modern strains are unable to survive in the wild without human support such as nitrate fertilization and pest control.⁸ (Imagine this bizarre situation in the world of domesticated animals: an animal able to exist only with human assistance, such as special feed or antibiotics, else it would die.)

      Differences between the wheat of the Natufians and what we call wheat in the twenty-first century are evident to the naked eye. Original einkorn and emmer wheat were “hulled” forms, simply meaning that the seeds clung tightly to the stem. Modern wheats are “naked” forms, in which the seeds depart from the stem more readily, a characteristic that makes threshing (separating the seed from the chaff) easier, determined by mutations at the Q and Tg (tenacious glume) genes.⁹ But other differences are even more obvious. Modern wheat is much shorter. The romantic notion of tall fields of wheat grain gracefully waving in the wind has been replaced by “dwarf” and “semi-dwarf” varieties that stand barely a foot or two tall, yet another product of breeding experiments to increase yield and reflecting the extensive genetic changes that this grass has undergone.

      SMALL IS THE NEW BIG

      For as long as humans have practiced agriculture, farmers have strived to increase yield. Marrying a woman with a dowry of several acres of farmland was, for many centuries, the primary means of increasing crop yield, arrangements often accompanied by several goats and a sack of potatoes. The twentieth century introduced mechanized farm machinery that replaced animal power and increased efficiency, providing another incremental increase in yield per acre. While production in the United States was usually sufficient to meet demand (with distribution limited more by poverty than by supply), many other nations were unable to feed their populations, resulting in widespread hunger.

      In modern times, humans have tried to increase yield by creating new strains, crossbreeding different wheats and grasses and generating new genetic varieties in the laboratory. Hybridization efforts involved techniques such as introgression and “back-crossing,” in which offspring of plant breeding are mated with their parents or with different strains of wheat or even other grasses. Such efforts, though first formally described by Austrian priest and botanist Gregor Mendel in 1866, did not begin in earnest until the mid-twentieth century, when concepts such as heterozygosity and gene dominance were better understood. Since Mendel’s early efforts, geneticists have developed elaborate techniques to obtain a desired trait, though much trial and error is still required.

      Much of the current world supply of purposefully bred wheat is descended from strains developed at the International Maize and Wheat Improvement Center (IMWIC), located at the foot of the Sierra Madre Oriental mountains east of Mexico City. IMWIC began as an agricultural research program in 1943 through a collaboration of the Rockefeller Foundation and the Mexican government to help Mexico achieve agricultural self-sufficiency. It grew into an impressive worldwide effort to increase the yield of corn, soy, and wheat, with the admirable goal of reducing world hunger. Mexico provided an efficient proving ground for plant hybridization, since the climate allows two growing seasons per year, cutting the time required to hybridize strains by half. By 1980, these efforts produced thousands of new strains of wheat, the most high-yielding of which have since been adopted worldwide, from Third World countries to modern industrialized nations, including the United States.

      One of the practical difficulties solved during IMWIC’s push to increase yield is that, when large quantities of synthetic nitrogen-rich fertilizer are applied to wheat fields, the seed head at the top of the plant grows to enormous proportions. The top-heavy seed head, however, buckles the stalk (what agricultural scientists call “lodging”). Lodging kills the plant and makes harvesting problematic. University of Minnesota–trained agricultural scientist Norman Borlaug, working at IMWIC, is credited with developing the exceptionally high-yielding semi-dwarf wheat that was shorter and stockier, allowing the plant to maintain erect posture and resist buckling under the large seed head. Short stalks are also more efficient; they reach maturity more quickly, which means a shorter growing season with less fertilizer required to generate the otherwise useless stalk.

      Dr. Borlaug’s wheat-hybridizing accomplishments earned him the title of “Father of the Green Revolution” in the agricultural community, as well as the Presidential Medal of Freedom, the Congressional Gold Medal, and the Nobel Peace Prize in 1970. On his death in 2009, the Wall Street Journal eulogized him: “More than any other single person, Borlaug showed that nature is no match for human ingenuity in setting the real limits to growth.” Dr. Borlaug lived to see his dream come true: His high-yield semi-dwarf wheat did indeed help solve world hunger, with the wheat crop yield in China, for example, increasing eightfold from 1961 to 1999.

      Semi-dwarf wheat today has essentially replaced virtually all other strains of wheat in the United States and much of the world thanks to its extraordinary capacity for high yield. According to Allan Fritz, PhD, professor of wheat breeding at Kansas State University, semi-dwarf wheat now comprises more than 99 percent of all wheat grown worldwide.

      BAD BREEDING

      The peculiar oversight in the flurry of breeding activity, such as that conducted at IMWIC, was that, despite dramatic changes in the genetic makeup of wheat and other crops in achieving the goal of increased yield, no animal or human safety testing was conducted on the new genetic strains that were created. So intent were the efforts to increase yield, so confident were plant geneticists that hybridization yielded safe products for human consumption, so urgent was the cause of world hunger, that products of agricultural research were released into the food supply without human safety concerns being part of the equation.

      It СКАЧАТЬ