Tuesday, October 28, 2014

BREEDING BETTER CROPS

Still Life 2.  Tomatoes are often grown in hot, dry climates. More than 13 gallons of water per tomato is needed. Growing less thirsty varieties would use less water and cut costs. Crossing domestic varieties with a wild relative from Peru's Atacama Desert is hoped to result in a tomato that will achieve both. (From National Geographic, Oct. 2014.) 








Genetic Modification is possible through a variety of methods, and the goal is to increase yields of crops in an increasingly challenging climate.Genetically Modified Foods get a lot of public attention, but there are different categories of Plant Breeding or plant modification that if clarified, could reduce controversy.

A recent Article in National Geographic Magazine, The Next Green Revolution, by Tim Folger, (Oct  2014) has listed five methods of Plant Breeding that explain the differences:


Traditional Breeding:
Desired traits are identified in separate individuals of the same species, which are then bred to combine those traits in a new hybrid variety. (This kind of  cross breeding has been used intentionally or by accidental selection since the origins of agriculture.) 

Interspecies Crosses 
Breeders also cross different but similar species. Modern wheat comes from such hybridizations, some of which happened naturally.

Marker-assisted Selection
When genes for a trait aren't precisely known, targeting a DNA marker near them can speed up breeding. It identifies plants with the trait even before they mature.

Genetic Modification
Genes identified in one species can be transferred directly to an unrelated species, giving it an entirely new trait - resistance to a pest, or perhaps to a weed killer.

Mutation Breeding
Seeds are irradiated to promote random mutations in their DNA. If a mutation happens to produce a desirable trait, the plant is selected for further breeding.

Rice, Corn, potatoes, wheat, and other plants are being studied with the goal of increasing yields, and to make some crops disease or pest -resistant, or in locations where weather threatens to destroy food security.




This Blogger's comments:
Over the past 10,000 - 50,000 years humankind has survived and adapted by adjusting to a variedand omnivorous diet, that was maintained by migrating seasonally to different food sources, locations or climates, and seemingly to also be able to eat a wide variety of kinds of foods with both nutritional and medicinal values to survive. Some individuals did not always survive the diverse organic chemistry their way of life provided or demanded. Those who did survive passed on their genes to the Earth's current populations. Never in our history have so many food sources been so drastically altered, or have so many diverse foods been available to us.

Some large seed companies have attempted to change a plant's genetic resistance to pesticides that destroy the pests that destroy crops, but the pests have adapted to be ever more resistant to the pesticides. How the poisons affect the food values of these crops and what potential harm is caused to people or animals that ingest these poisoned plants or  domestic animals is a concern, that is frequently denied by distributors, and may be ignored entirely.

It is commonly known that selecting foods that are sweeter, starchier, or fatter has not resulted in a healthier human species. A common fear is that changing the delicate organic chemistry of many of our food staples could produce dietary deficits, unhealthy imbalances of harmful elements in our diet, or even ultimately poison us. That is why testing of these new varieties and their impacts upon populations that eat them, seems very important.

The very least option should be that we have the choice to refuse to eat the artificially created genetically modified foods. We deserve to have consistent food labels that have a dependable definition throughout the country and hopefully throughout the world.


The above image and Blogger's Comments are the Copy Right of Ruth Zachary.