Notice also how the article describes the green revolutions of the
19th century, which were classical cases of inter-species
cross-breeding using non-Mendelian plant breeding techniques.
http://www.idrc.ca/evaluation/ev-115017-201-1-DO_TOPIC.html


The CGIAR made two mistakes when setting up these large and expensive
international research centres. First, they deliberately created
scientific monopolies in the non-industrial world. All the money
available for research on a particular crop would go to a single
research centre. If two centres, such as CIAT and IITA, had
over-lapping areas of research, they were carefully controlled to
ensure that they did not compete with each other. The justification
for this was to avoid unnecessary duplication. Research is expensive
and, it was argued, duplication makes it doubly expensive.

But, in fact, duplication in research is essential, because it
provides the competition which is so necessary for good science.
Nothing stimulates a scientist more than the thought that a rival
scientist may anticipate him, and publish first. And nothing dulls a
scientist more than the knowledge that he has no rivals. The
scientists at the International Research Centres have few rivals, and
those they do have are critically short of research funds.

The second mistake was fundamental. It was the hope that these
International Centres would produce new green revolutions. They did
not. Indeed, they are a classic illustration of the completely false
idea that you have only to throw enough money at enough scientists, in
order to get new scientific breakthroughs. The original inspiration
for good science comes from the scientists themselves, and usually
from an individual scientist who, as often as not, is grossly
under-funded, and probably working in an ancient laboratory that has
been due for demolition for decades. Scientific inspiration does not
come from money. Nor does it come from politicians, administrators, or
bankers.

The CGIAR produced no new green revolutions for one very simple
reason. All the plant scientists employed by the international centres
had been trained in the traditions of the Mendelian school of
genetics. They believed that, when breeding plants for parasite
resistance, you must first find a genetic source of resistance. If no
source of resistance could be found, the resistance breeding could not
even begin. You then had no choice. You had to use crop protection
chemicals. For these members of the Mendelian school, there were
really no other possibilities.

The International Potato Centre (CIP) was possibly the worst in this
respect. For years its scientists were telling the world that there
was no such thing as horizontal resistance. Vanderplank's writings
were ignored. John Niederhauser's work in Mexico was ignored. My own
later, and much less important, potato work in Kenya was also ignored.
John Niederhauser who, by rights, should have been in charge of CIP
research, was rigorously excluded from its affairs. On the one
occasion that I visited the place, I was shouted down during a
scientific meeting. In fairness, however, I must comment that this was
many years ago, and that CIP is now greatly improved. Nevertheless,
the CGIAR International Centres, as a group, have a really dreadful
record of ignoring horizontal resistance.
Secondary Problems in the Green Revolution

The miracle wheats and rices both ran into what the members of the
Mendelian school called "secondary problems". This is because there
are vertical resistances in the miracle wheats and rices, and these
resistances fail periodically. On one occasion in Mexico, many tons of
special fungicide had to be airlifted from Europe, at huge expense, as
an emergency measure, to save a large area of wheat whose vertical
resistance had broken down. A large proportion of the research budgets
of CIMMYT and IRRI are spent on "maintenance research" which is their
euphemism for the production of new cultivars to replace those whose
vertical resistances have failed.

Rice has vertical resistance to one of its diseases, called "blast"
(Piricularia oryzae), and one of its insect pests, called the brown
plant hopper (Nilaparvata lugens). Blast disease has proved an
intractable and recurring problem because of endless failures of
vertical resistance. The brown plant hopper has proved even worse
because, when the vertical resistance to it failed, the miracle rices
were so susceptible that there were unheard of population explosions
of this pest. There were so many hoppers around that they invaded
neighbouring, resistant rice crops in huge numbers. These crops were
often old, local landraces which had an adequate level of horizontal
resistance to control normal infestations of brown plant hoppers. But
their resistance was entirely inadequate to control this parasite
interference, and the abnormal, and artificially induced, levels of
infestation.

It was at this sad and sorry point that subsistence farmers in the
non-industrial world were advised, for the first time ever, to start
spraying their rice crops with crop protection chemicals. However,
there is a happy ending to this story. Peter Kenmore, an American
entomologist working in the Philippines, introduced IPM methods
(Chapter 14) to the rice farmers of this country. He has been
dramatically successful in reducing the use, and the cost, of
insecticides while, at the same time, increasing the yields of these
rice crops. His success is an example to the rest of the world. And
his success will be even greater when the rice breeders finally
produce new varieties with high levels of horizontal resistance.

Another problem is that the miracle wheats and rices have proved to be
abnormally susceptible to a few diseases which were previously quite
unimportant. The miracle wheats have little resistance to Septoria
diseases, for example, apparently because these fungi have a low
epidemiological competence in Mexico, where the wheats were bred and
selected. These diseases are now of major importance in other parts of
the world where the fungi have a considerably higher epidemiological
competence.

The miracle rices were selected in the Philippines and they too had
abnormal susceptibility to parasites which either do not occur, or
which have a low epidemiological competence, in that area. For
example, some of the miracle rices could not be grown in India because
of a bacterial blight, and a virus disease called "tungro".
No New Green Revolutions

Interestingly, the entire green revolution was based on two
characters, the short straw of wheat, and the short straw of rice,
which are both inherited in a Mendelian fashion. This, of course, was
a tremendous boost for the Mendelian school of plant breeding.
Suddenly, for the first time in half a century, the members of the
Mendelian school had found characters whose inheritance was controlled
by only a few genes, apart from resistance to parasites, that were of
major economic and agricultural significance. In spite of the
secondary problems, the dwarf wheats and rices were undoubtedly the
two most important agricultural achievements of the second half of the
twentieth century, and they were the result of Mendelian inheritance.
More than ever, the Mendelian pedigree breeding methods became
"mainstream" science.

This simple fact has had two very profound consequences. First, it
confirmed and prolonged the domination of plant breeding by the
Mendelian school of genetics. The green revolution was claimed as a
new triumph of this school. It should, perhaps, be regarded as the
last gasp of the Mendelian school.

It is possible, although rather unlikely, that a Mendelian character
of major agricultural importance has still to be discovered. Crop
science has had nearly a century in which to find such characters and,
bearing in mind that virtually every crop geneticist was a member of
the Mendelian school, they have not found many. Just short straw in
wheat and rice, and vertical resistances. All other single-gene
characters, such as seed and flower colour, are of quite minor
economic significance.

Secondly, no new green revolutions were produced by the expensive,
monopolistic, international research centres because no one could find
even one new Mendelian character that could make such a revolution. If
we are to have new green revolutions as, indeed, we probably can, and
will, they are more likely to emerge from quantitative genetics, and
from breeding plants for quantitative resistance which is durable,
complete, and comprehensive.

There have been other green revolutions, in the past, although they
were never called this. The development of sugar beet from fodder beet
(Chapter 2) in the nineteenth century created an entirely new crop,
and entirely new beet sugar industries, in many temperate countries.
The breeding of sugarcane, which started in the late nineteenth
century, had just as dramatic an effect on sugarcane production as did
short straw on wheat and rice cultivation. The development of hybrid
maize in the United States, and later most of the world, was even more
important. Similarly, the breeding of new soybean varieties
transformed an insignificant crop into the largest crop of all in the
United States. These developments all depended on quantitative
genetics. On the few occasions when Mendelian characters were
employed, they were a positive nuisance, because they provided
vertical resistance to parasites, and nothing else.

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