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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.

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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.
From the perspective of the developing world, there is a set of priorities we can deduce:
  • increase food production, and particularly the production and availability of nutritious foods
  • develop strong(er) national economies, potentially developing export markets for local products
  • make sustainable and efficient use of ecosystems
  • These are not the same priorities we can deduce from the actions of developed countries. They want to:
  • establish new and enlarge old export markets
  • develop an infrastructure that can successfully support emergency response (e.g. in the sub-Saharan Sehel)
  • Are these the same priorities, or even complimentary?
Are there actions that would work towards priorities in both the developed and developing worlds?
  • The development and application of technology to improve productivity through plant cultivar selection and through agricultural techniques.
  • Improve sustainability through land use and resource management
  • ‘Protect’ and manage change through stable governance (no more Lysenkos reversing or preventing progress)
Cultivar selection

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).


Wild type


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.

Different glucosinolates act in different ways:
  • sulforophane is released when cauliflower is chopped or chewed. It is an anti-cancer chemical.
  • indole-3-carbinol is an anti-estrogen that slows or prevents cancers of the breast and prostate.
  • other glucosinolates enhance the liver’s ability to detoxify carcinogens.
  • However, economically and in terms of productivity the “Green Revolution” has had far greater, though controversial, impact…
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

What was Borlaug’s background, and what did he achieve?
  • he began as a microbiologist for E.I. Dupont
  • quit Dupont and moved to Mexico to establish CYMMT with funding from the Rockefeller and Ford Foundations
  • selected for wheat varieties that produced high yields. Also selected for high seed:shoot ratios, rust resistance and dwarfing to reduce lodging
  • productivity increased dramatically in the varieties he selected. Here is a figure from one of his speeches:
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

3. irrigation

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.

The Ogallala


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.

So how are we to feed a growing human population? What will produce a sustainable and sufficient amount of food?
  • Move away from large scale, year-after-year monoculture of
  • a few high-yielding varieties. A long-term sustainable agriculture with restricted use of fertilizers and pesticides depends on more than crop rotation; it will probably require polyculture – growing a number of complimentary crops together in the same fields.
  • 2. Protect the germplasm of the many landraces that are the sources of modern cultivars. Another problem from the success of the Green Revolution has been that what was once a diverse agriculture of many varieties has become limited to the growth of only a few varieties. Many of those varieties are hybrids. The hybrid vigor of the F1 generation in most cases is lost if those F1s are crossed.
2. (cont.) Farmers are thus dependent on seed companies to
  • provide F1 seed each year. That’s great for agribusiness,
  • but not for smaller farmers. Not only due to cost, but also
  • because the farmers are driven away from older genotypes.
  • We now depend on gene banks to preserve the genes of the
  • old landraces. The idea of genebanks (and seedbanks) for
  • agriculture dates at least back to Vavilov.
  • 3. The second phase of the Green Revolution may be a
  • “Brown Revolution”. It responds to the changes of the first
  • phase by emphasizing:
  • sustainable varieties selected and tailored to specific regions and practices
  • varieties that represent a compromise between yield and risk (and is that risk varietal or environmental?)
3. cont.
  • reduction in the intensity of management, i.e. irrigation, fertilizer, pesticides, and the requirement for mechanization
  • improved tillage practice (reduced tillage eliminating plowing and disking fields or no tillage)
  • intercropping, polycropping, and/or crop rotation
  • use of GMOs – there are interesting legal implications of this. Saskatchewan farmer Percy Schmeiser was sued for having the genes from genetically
  • manipulated, ‘round up ready’ canola in his fields – not from planting, but from crossing with GM plants in other fields.
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.

decorative lupins

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.