Feeding a Hungry World There are many experts who claim that agricultural production globally is sufficient to feed the current human population.
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Feeding a Hungry World
There are many experts who claim that agricultural production globally is sufficient to feed the current human population.
However, that assumes that the human population is feeding equitably on those resources. Are we (and the rest of the developed world) willing to adjust our lifestyles to achieve that global balance?
We produce more than we need, and export food products to many places. Are those exports going where they are needed? Can the developing world afford to pay reasonable prices for our food exports?
On one hand, that leads to foreign aid to support developing countries. On the other, it leads to development of aid packages to help others to help themselves.
Here is the FAO ‘hunger map’. Colours indicate different proportions of nation’s populations that are malnourished.
Cultivar selection has occurred for about 10 centuries.
Initially this occurred by hand pollinating plants that had desirable characteristics, e.g. the picture in the text of hand pollinating date palms.
More recently, with a knowledge of inheritance, it has occurred by trait selection. Selection can produce radically different varieties from a single source. Probably the most dramatic example is selection on Brassica oleracea to produce: kale, collard greens, kohlrabi, cabbage, cauliflower, broccoli and Brussel sprouts.
This species is native to coastal southern Europe and western Europe. It was cultivated to consume its leaves by Greek times. At that point it appears that something like kale had been selected (described as having curly leaves).
Kohlrabi was produced by selecting for lateral growth of meristem tissue…
Brussel sprouts were produced by selecting cabbage’s expansion of green leaf buds into the small ‘cabbages’ we eat. Fore-runners were cultivated in ancient Rome, and the modern type were first cultivated in the 1200s in what is now Belgium.
Cabbage is also closely related to the source plant, and originated in the Mediterranean region. It was already selected in Greek times, produced by selecting for short internode length. The ‘head’ is the mass of leaves caused by that selection.
Broccoli and cauliflower are both expanded flower heads, one green and the other white.
All Brassica oleracea share characteristics of high nutritional fibre and vitamin C. All (but particularly broccoli and cauliflower) contain glucosinolates that are believed beneficial as anti-cancer compounds.
The Green Revolution
The single largest event in plant breeding for the developing world was the “Green Revolution”. It is identified with Dr. Norman Borlaug, who developed high-yielding, non-lodging wheat strains in Mexico (with Rockefeller Foundation support) at the International Centre for Maize and Wheat Improvement (CIMMYT). Since there was no subject area appropriate to recognize his achievement, he was given the Nobel Peace Prize in 1970.
green revolution wheat in India
From Borlaug’s Nobel lecture:
“Almost certainly, however, the first essential component of social justice is adequate food for all mankind. Food is the moral right of all who are born into this world.”
As the figure showed, potential, as well as actual food production in developing countries was increased enormously, by a factor of 3 or more.
However, the ‘Green Revolution’ is not without costs that are difficult for developing nation farmers to manage. The high-yielding varieties developed depend on:
1. use of 2x as much fertilizer as other, non-green revolution varieties
2. use of ~3x as much pesticide
4. equipment and fuel needed for mechanized harvest
The seeds of high-yield varieties are also much more expensive than those of ‘ordinary’ cultivars.
High yield varieties are not grown only in the developing world. They are also the basis of North American agriculture.
The same problems that affect ecology and success of Green Revolution crops in developing countries impact farmers in the U.S. and Canada.
In the grain belt of the U.S., water for irrigation is becoming a serious problem, especially with population growth in the dry southwest. The water source is the Ogallala Aquifer. It is rapidly being drawn down.
That has led to some extreme engineering solutions being suggested: to draw water from the Great Lakes, or even from James Bay, to replenish the Aquifer.
Water to replenish the Ogallala aquifer is not flowing anywhere near as rapidly as the source is being diminished. Sinkholes develop where surface collapse occurs as water beneath is withdrawn.
In California’s Central Valley continuous irrigation is leading to increasing soil salinity, which will eventually reduce yield.
Monsanto tried to sue him for a ‘technology fee’ (a license to use the GM genes).
Monsanto won because Schmeiser knowingly planted the next year’s crop with GM seeds (saved from the previous year’s harvest), but got no fee or damages.
The question of “gene ownership” remains. The question is probably more important if you think about it in terms of human genes. Biotechnology companies are patenting human genes for various chemicals produced in our bodies.
Questions of legal ownership are certain to make many lawyers rich for years!
There will be more about GMO and genetic modifications later.
In addition to selection to improve strains and productivity, there have been recent efforts to develop new crop species. Some you’ve seen already: quinoa and amaranth.
You’ve seen and tasted it as a ‘grain’. In the agriculture of the Andes both the seeds (‘grain’) and the leaves are eaten.
Quinoa is rich in protein (12 – 18%) compared to most grains, and is particularly valuable because most grains do not have high levels of lysine (it has high lysine) and even legumes are typically low in methionine (it also has methionine). It also, while low in fat (4 – 9%), has a high proportion in the form of an essential fat, linoleic acid.
Again here, both leaves and seeds are valuable food sources. Protein content is reasonably high (12 – 18%) and is also high in lysine. Fat content is moderate (6 – 10%) and, like quinoa, is rich in linoleic acid.
In addition, it is a valuable source for squaline, a fatty acid used synthesizing steroids (various medical uses) and cosmetics.
Apparently it can be popped, like tiny popcorn, and that is one of the traditional native ways of eating it.
Tarwi is a South American legume. Its seeds have very high protein (46%) and fat (20%) content. Tarwi is also from Andean highlands, and is only now beginning to be explored for cultivation and to select cultivars with reduced alkaloid (i.e. toxin) content.
Tarwi is in the genus Lupinus, which also includes a wide variety of ‘lupins’ that are favoured roadside and garden flowers. As a cool climate (remember, it comes from Andean highlands) legume with lots of oil comparable to peanut oil, you can expect this species to be developed into a valuable crop within the next few years.
Tamarillo is a South American tomato relative. Its common name is ‘tree tomato’. That should remind you that its leaves are inedible, but its fruit is tasty and very edible.
Tamarillos, like tomatoes, are a rich source of vitamins (A, B’s, C and E) and minerals.
Tamarillos are already cropped in New Zealand and very popular there. Commercial export is being developed.
Naranjilla is also an Andean fruit, and is classed with tamarillos (though not really related) because the English common name is ‘apricot tomato’.
It is the juice of this fruit that is consumed in the South American tropics (and now into Central America). Commercial development on any larger scale has really not occurred.