Introduction to Open Plant Breeding: Vertical and Horizontal Resistance Explained

This is a slideshow introduction of open plant breeding, explaining the difference between vertical and horizontal resistance.

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Basic Principles in Horizontal Resistance Breeding

This slideshow covers the basic principles in breeding crops for horizontal resistance.

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Biological Control and Biological Anarchy

In crop science, biological control has two distinct meanings. The first involves the deliberate importing of biological control agents to solve weed or pest problems. Classic examples are the control of weed cactus in Australia by insect parasites imported from Mexico, and the control of rabbits with the myxomatosis virus. This form of control can be extremely effective, but it is usually limited to the control of an imported, foreign pest by parasites from that pest’s centre of origin.

The second meaning refers to the use of the normal biological control agents of an indigenous pest or pathogen. These control agents may be predators, hyper-parasites, antagonistic micro-organisms, or organisms that trigger defence reactions in the host. The cultivation of such control agents for release into greenhouses can be an effective technique.

Biological anarchy is the converse of biological control. It is a situation in which biological control has failed, either because the control agents are absent from the area in which a foreign host species is growing, or because the control agents of an indigenous host have been largely destroyed with pesticides. The pest or pathogen then runs riot and can be an infernal nuisance. The best way to restore the indigenous biological control agents is with horizontal resistance. And the best way to enhance the effects of horizontal resistance is to restore the biological controls. The two phenomena are mutually re-enforcing.

Integrated pest management (IPM) is a technique used mainly by entomologists to enhance biological controls. It involves careful monitoring of insect populations in order to reduce insecticide applications to the absolute minimum.

Crop vulnerability and phytosanitation

One of the advantages of the Open Plant Breeding Foundation is that it can operate internationally with various members exchanging information and genetic material between countries. It is a great idea for amateur breeders to cooperate internationally but, before they do so, they must respect their countries’ phytosanitary regulations, which exist to protect against crop vulnerabilities.

Crop vulnerability means that a crop is susceptible to an epidemiologically competent pest or disease which is absent from the area in question. If that pest or disease is introduced, the vulnerability becomes real, and potential damage becomes actual damage. For example, although it has epidemiological competence in the United Kingdom, the Colorado beetle does not occur there, and the potato crops of that country are highly susceptible to it. This is a fairly extreme crop vulnerability. An even greater vulnerability is the area of wheat that is susceptible to the Ug99 strain of stem rust (see knowledge base)

The term phytosanitation (Gk. Phyto = plant; L. sanita = health) refers to the use of healthy planting material as a means of restricting the spread of dangerous crop pests and diseases. The primary purpose of phytosanitation is to prevent vulnerability threats from becoming reality. Phytosanitation can be used at the international, regional, and local levels, and it is usually backed by the force of law.

International phytosanitation involves international treaties and official certification of planting materials being transported across national boundaries. Your agricultural department can tell you the certification requirements for the material you wish to import. Bear in mind that some imports are totally forbidden.

International phytosanitation functions best with island nations, such as Japan, Australia, New Zealand, United Kingdom, Eire, Madagascar, and many smaller, islands, both tropical and temperate. Most of these islands are isolated from much natural dispersal, and they have complete control of all their air and sea ports. Understandably, their phytosanitationary regulations are usually quite strict.

The general rule is that true seeds are relatively safe, while vegetative propagation material (e.g., cuttings, tubers, rhizomes, bulbs, corms) are the most dangerous, particularly if they have soil adhering to them. Accordingly, vegetatively propagated crops are generally risky, while seed propagated crops are considerably less so.

Organic farmers should appreciate that many phytosanitationary regulations insist on seeds being dressed with a fungicidal and/or insecticidal seed dressing. If this flouts the organic status of their farms, they should arrange for that seed to be multiplied on a conventional farm.

Regional phytosanitation is the least effective because it is not feasible to check every car, plane, and train moving from one part of a country to another. Even when an international land border is involved, such as that between Canada and the USA, or that between France and Germany, an effective control of the transport of plant material is extremely difficult, and natural dispersal cannot be prevented.

Local phytosanitation functions best on an individual farm, because the individual farmer has control of everything that is brought on to his land. For example, he can take great pains to ensure that his new seed is not carrying a dangerous pest or disease that is absent from his farm.

Whatever amateur breeders may choose to do, they must stay legal. Quite apart from getting into trouble with the law, infringement of phytosanitationary regulations could cause devastation because of serious crop vulnerabilities that most people do not even know about. Please be responsible and consult your agricultural department.

Erosion of Horizontal Resistance

Even though horizontal resistance will not break down like vertical resistance, it can be eroded quantitatively. This is an alarming thought for anyone who values the idea that horizontal resistance is durable resistance. However, this erosion is easily avoided, and it is unlikely to be serious if it does occur, but it is still important to understand it.

There are four kinds of erosion of horizontal resistance:

Host erosion

A host erosion results from genetic changes in the host population. This can occur during the cultivation of a genetically flexible crop grown in the absence of the parasite, such as maize which is open-pollinated. But it does not occur during the cultivation of a genetically inflexible crop, such as a clone or pure line, even when the parasite is absent.

A host erosion can also occur during the breeding of any crop in the absence of a parasite, particularly if the screening population is protected by a functioning vertical resistance or by a pesticide. It is then known as the vertifolia effect.

Parasite erosion

A parasite erosion results from genetic changes in the parasite population. This is important only occasionally, and only with facultative parasites. For example, a soil-borne Fusarium or Verticillium wilt fungus might have a low parasitic ability. But that parasitic ability could increase if a susceptible host were grown repeatedly on the same land.

A parasite erosion was seen repeatedly in North America as settlers moved west and cultivated flax on virgin land. The native Fusarium wilt would gradually increase its parasitic ability until flax cultivation became impossible, and it moved west to new virgin land with new settlers. It was said that the linseed oil factories had a very high rate of being insured, and then burning to the ground, as flax cultivation moved west. Eventually, the flax accumulated so much horizontal resistance that this problem disappeared.

Environmental erosion

An environmental erosion results when a cultivar is taken from an area of low epidemiological competence, and is cultivated in an area of high epidemiological competence.

For example, bacterial wilt of potatoes lacks epidemiological competence entirely in temperate areas, and potatoes that have been bred in a temperate area are likely to be very susceptible to it. This lack of horizontal resistance becomes obvious only when those potatoes are grown in a tropical or subtropical country where the wilt has a high epidemiological competence.

False erosion

A false erosion results from sloppy experimental work, when a cultivar is thought to be resistant and is later found to be susceptible. It is very tempting to blame nature rather than oneself for this kind of error.

A false erosion can also occur over a long period of breeding when a cultivar used as a standard of susceptibility appears to become increasingly susceptible. This is an illusion resulting from the fact that all the other plants in the breeding program are becoming increasingly resistant, and the discrepancy between susceptible and resistant slowly widens.

Macro-evolution and micro-evolution

Darwinian evolution is usually divided into macro-evolution (Greek: macro = large) and micro-evolution (Greek: micro = small).

Macro-evolution has the following characteristics:
1. it requires periods of geological time
2. it functions primarily at taxonomic levels above that of a species
3. it leads to an increased complexity
4. it produces new genetic code
5. it produces new species
6. it is irreversible

Micro-evolution is the converse in all of these characteristics:
1. it requires periods of historical time
2. it functions at taxonomic levels below that of a species
3. it does not lead to an increased complexity
4. it does not produce new genetic code; it merely rearranges existing code
5. it produces differing ecotypes
6. it is reversible

Both ancient domestication and modern plant and animal breeding involve micro-evolution. But, in each case, the micro-evolution results from artificial selection rather than natural selection. Inevitably, the distinction between the two kinds of evolution is blurred. The artificial selection produced new agro-ecotypes, although taxonomists have dignified most of them as new species with their own Latin names, particularly when polyploidy was involved. However, if left to themselves in a wild ecosystem, most agro-ecotypes would either revert to their wild form, or they would become extinct. Natural selection would undo artificial selection quite quickly, within a short period of historical time.

New encounter, Old encounter, and Re-Encounter Parasites

Some important influences of the origins of crops on pest and disease susceptibility were first recognised by Buddenhagen (1977).

A new encounter parasite is one which evolved away from its agricultural host, usually on a closely related wild host species. A classic example is potato blight (Phytophthora infestans) which evolved in Mexico and was brought into contact with cultivated potatoes by people. Another example is the Colorado beetle (Leptinotarsa decemlineata) which occurs wild in Colorado, USA, and became a savage pest of cultivated potatoes. Similarly, bananas in Latin America came into contact with Fusarium oxysporum f.sp. cubense which is now a major infliction called Panama disease. When the old and new hosts are closely related, a new encounter parasite can be very damaging.

An old encounter parasite is one which had been in contact with is crop host ever since that crop was domesticated. Wheat rust (Puccinia graminis) is a typical example. Old encounter parasites are generally less damaging unless there has been a severe vertifolia effect.

A re-encounter parasite is one that is left behind when the cultivated host is taken to another part of the world. At a much later date, the parasite is also taken to the new location where it is often very damaging because the host has lost resistance during its cultivation and breeding in the absence of that parasite. The classic example of this was maize in tropical Africa which was re-introduced to the Central American tropical rust (Puccinia polysora) after about four centruies of cultivation in its absence.

Reference:

Buddenhagen, I. W. (1977): Resistance and vulnerability of tropical crops in relation to their evolution and breeding, in The Genetic Basis of Epidemics in Agriculture (P.R. Day, Ed) Ann. New York Acad. Sci., 287: 309-326

Parasite Interference

Crop scientists use statistically controlled field trials to make all sorts of comparative measurements such as the yields of cultivars, the best spacing between rows, and within rows, the optimum fertiliser applications, and so on. The statistics are mathematically quite complicated, but modern computer software has largely eliminated this difficulty. These statistically controlled trials can be very accurate. However, the statistics are not accurate and, indeed, are positively misleading, when it comes to measuring pests and diseases.

Vanderplank (1963) first recognised this problem, which he called the ‘cryptic error’ in field trials. The problem is caused by the fact that crop parasites can move from one plot to another within a field trial, and this can ruin statistical analyses. The phenomenon was renamed inter-plot interference and, finally, became parasite interference, when it was appreciated that it was also highly relevant to the screening of individual plants in recurrent mass selection. This is because parasites can also move from plant to plant, and a resistant plant surrounded by susceptible plants can have its resistance obscured by parasite interference. Parasite interference can increase the amount of damage by several hundred times (James, et al, 1973) and, if not recognised can be incredibly misleading .

Parasite interference is possibly at its most misleading in a wheat breeding technique known as ‘head to row’ screening, also known as family screening. In this technique, all the seeds from one head of wheat are sown in a single row, or family. The idea is to select the best families first, and then select the best individual in each family. Genetically, this makes a lot of sense but, in breeding for resistance, it is a disaster. Consider the following diagram.

Each of the boxes labelled A-E represents a single row, a single head of wheat. A red box has the maximum parasitism, while a green box has zero parasitism. A yellow box has a level of parasitism approximately halfway between the maximum and the minimum levels of parasitism. The red boxes A, C, & E all have vertical resistance gene 1 and their resistance has been matched. They have low levels of horizontal resistance and, consequently, they have the maximum parasitism. They are also interfering with Rows B and D, and are loading them with parasites in the process of parasite interference.

Row B also has vertical resistance gene 1 and the parasite interference is consequently matching allo-infection. But row B also has a high level of horizontal resistance. Unfortunately, this horizontal resistance cannot be observed because it has been swamped by matching parasite interference. This is the family that the breeder should have kept but which was invariably thrown out.

Row D, on the other hand, has vertical resistance gene 2 and the parasite interference is consequently non-matching allo-infection, and D looks perfect, except for damage due to hypersensitivity flecks (see below). But its very low level of horizontal resistance is completely obscured, and its vertical resistance is unstable. It is the very opposite of perfect. This is the family that the breeder should have thrown out but which was invariably kept.

When working with head-to-row plots, the parasite interference can be so intense that the hypersensitive flecks of non-matching allo-infection appear to be a serious disease. Small grain cereal breeders used to point out that this was not true disease, and that such damage would not occur in farmers’ fields, where the non-matching allo-infection was negligible. But, it seems, they never did consider the effects of a comparable interference on a high level of horizontal resistance, when the allo-infection was all matching infection.

These misleading effects of parasite interference are the main reason why crop scientists neglected horizontal resistance in favour of vertical resistance for most of the twentieth century.

Finally, when working with recurrent mass selection, it is imperative to use relative assessments of resistance. That is, the least parasitised individuals are selected, regardless of how severely parasitised they may be. Most of that parasitism will be the result of interference which will not occur in farmers’ fields.

References:

Van der Plank, J.E. (1963): Plant Diseases: Epidemics and Control. Academic Press, New York & London, 349pp.

James, W.C., Shih, C.S., Callbeck, L.C., & Hodson, W.A. (1973): Interplot interference infield experiments with late blight of potato (Phytophthora infestans), Phytopath., 63: 1269-1275.

Stable and Unstable Protection

All mechanisms of protection against crop pests and diseases can be classified into one of two categories. Stable mechanisms do not break down to new strains of the crop parasite. They provide durable protection. Unstable mechanisms do break down in this way, and they provide only a temporary protection.

Host Resistance

Vertical resistance involves single genes taken from a gene-for-gene relationship. Any combination of these genes operates against some strains of the crop parasite but not others. Its function is to reduce the frequency of matching allo-infections. Vertical resistance consequently fails to function on the appearance of a new, matching strain of the parasite. It provides an unstable protection.

Horizontal resistance, on the other hand, is the resistance that invariably remains after vertical resistance has been matched. Its function is to protect the host against matching allo-infections, and it operates equally against all matching strains of the parasite. It provides a stable protection.

Insecticides

Most natural insecticides provide a stable protection. In the Far East, rotenones (extracted from derris roots) have been used for centuries against body lice without any resistant strains appearing. Similarly, pyrethrins (extracted from the flowers of pyrethrum) have also been used for centuries to control fleas and bed bugs in Dalmatia without any resistance developing. Oils on water provide a stable protection of mosquitoes, and on stored beans a stable protection against weevils.

Most synthetic insecticides are unstable. DDT-resistant houseflies are the best known example.

Fungicides

The famous Bordeaux mixture is a stable fungicide as well over a century of use have demonstrated. So too are other copper formulations and the bisdithiocarbamate fungicides. But fungicides such as metalaxyl are unstable.

Antibiotics

It seems that all antibiotics are unstable, as our medical colleagues know to their cost.

The Advantages of Horizontal Resistance

Breeding plants for horizontal (i.e., many-gene) resistance is very easy, while breeding for vertical (i.e., single-gene) resistance is highly technical, very difficult, and very expensive.

Vertical resistance requires a ‘good source’ of resistance, which does not always occur. But it is possible to breed for horizontal resistance to any pest or disease, using only susceptible parents.

Horizontal resistance is durable resistance. It never breaks down to new strains of the pest or disease, as does vertical resistance. This means that the breeding is cumulative. A good cultivar need never be replaced, except with a better cultivar.

Horizontal resistance is a quantitative variable, and it exhibits every degree of difference between a minimum and a maximum. In the absence of crop protection chemicals, the minimum level of horizontal resistance usually leads to a complete loss of crop, while the maximum level of horizontal resistance leads to a negligible loss of crop. It is easy to breed for the maximum level.

Horizontal resistance can be accumulated for every locally important crop parasite. We can thus produce resistance that is durable, complete, and comprehensive. The need for insecticides and fungicides then disappears.

Most heirloom varieties have fairly high levels of horizontal resistance. But most modern varieties have rather low levels because horizontal resistance tends to be lost during breeding for vertical resistance, which has been the resistance of choice among professional breeders for the past century. This is because of the vertifolia effect.

The One-Pathotype Technique

This is a slideshow that introduces the one-pathotype technique, which is a way of making sure that no vertical resistances are throwing off the results of a breeding program. It is the only aspect of horizontal resistance breeding that can be difficult for amateurs.

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The Vertifolia Effect

The vertifolia effect was discovered by Van der Plank (1963) who named it after a potato cultivar of this name, in which the effect was very pronounced. The vertifolia effect is a loss of horizontal resistance which occurs during breeding for vertical resistance. Its meaning was later extended to include the loss of horizontal resistance that occurs during breeding under the protection of pesticides.

The level of horizontal resistance can only be assessed by the level of parasitism. Clearly, if there is no parasitism because of a functioning vertical resistance, or a pesticide, the level of horizontal resistance cannot be assessed. Because individual plants with a high level of horizontal resistance are rather rare in a mixed screening population, the chances are that individuals with a relatively low level of horizontal resistance will then be selected on the basis of their other attributes. The loss is usually quite small in a single breeding cycle but, after many cycles, it can become very serious indeed.

The prime example of the vertifolia effect is the loss of horizontal resistance to potato blight (Phytophthora infestans) that has continued ever since both the discovery of Bordeaux mixture in the late nineteenth century, and the discovery of vertical resistance in the twentieth century. A loss of horizontal resistance to cotton pests has continued ever since the discovery of DDT in the 1940s.

The vertifolia effect is a very modern phenomenon. Its overall consequences are seen in the high levels of horizontal resistance in heritage cultivars, when they are compared to modern cultivars. This is the main reason why heritage cultivars are so valued by organic farmers.

One of the main objectives of most amateur plant breeders will be to restore the horizontal resistances that were lost to the vertifolia effect.

Reference:
Van der Plank, J.E. (1963): Plant Diseases; Epidemics and Control. Academic Press, New York & London, 349pp.

University Plant Breeding Clubs

A special feature of university breeding clubs is the university ambience. Students are far more likely than amateurs to overcome the intimidation, and the initial hesitation, about breeding crops for horizontal resistance. The students would do all the work of breeding, supervised and guided by a professor. This would provide them with the initial ‘ice‑breaking’ and the essential ‘hands-on’ experience. The students would earn course credits from their club membership, and their teacher would earn teaching credits.

The main function of university breeding clubs is to teach. This teaching will promote a widespread proliferation of breeding clubs. Graduates, with life membership in their clubs, will most likely return to their family farms, or become agricultural scientists. If they become farmers, they might initiate one or more farmers’ breeding clubs in their own locality. If they become scientists, they might initiate one or more private breeding clubs among concerned amateurs in the vicinity of their work. Or they may become entrepreneurs themselves, relying on breeder’s royalties to earn a living.

In any event, both the concept and the practice of plant breeding clubs will begin to spread. As increasing proofs of the viability of horizontal resistance, and the ease and usefulness of amateur breeding, begin to accumulate, the proliferation of clubs will increase. The public interest in pure food, and a clean environment, to say nothing of the farmer interest in high yields and cheap production, is so strong that the process of growth and proliferation will increase exponentially.

That these developments have not occurred before now is due to a lack of knowledge. No member of the public was even aware of this possibility. The professional plant breeders, in their breeding institutes, have had no interest in promoting either amateur breeding or horizontal resistance. Indeed, they genuinely believed both to be impractical, if not impossible. And the chemical corporations, with their concept of crop protection chemicals substituting for host resistance, have also had no interest in promoting horizontal resistance.

The advantages of plant breeding clubs, particularly university clubs, over institutional and corporate plant breeding, are so marked that they merit emphasis.

Advantages for the students

Overcome the initial intimidation.

For anyone who has not tried it before, the very thought of plant breeding is somewhat intimidating, in the same way that the first use of a computer, or the first dive into deep water, is intimidating. Once this intimidation is overcome, plant breeding for horizontal resistance turns out to be very easy, and very rewarding. The ambience of a university breeding club is undoubtedly the best way of overcoming this intimidation, but this comment should not discourage other amateurs from starting their own clubs.

Learning to breed for horizontal resistance.

The use of computers cannot be learned from manuals, and ‘hands-on’ experience is essential. The techniques of breeding for horizontal resistance also require ‘hands-on’ experience and a breeding club is the best means of providing such experience. The students themselves would do all the work of breeding and they would gain practical experience in every aspect of the breeding process.

Improved participation and interest.

Many agricultural students, who grew up on a farm, find there is a gap between their own farming experience and the somewhat academic teaching within the university. A breeding club closes this gap very effectively, and it demonstrates the practical utility of various scientific concepts. The club also provides students with active participation, and a sense of achievement, as alternatives to passive learning.

Earn course credits.

As one of the inducements to join, students should earn course credits from their breeding club membership and participation.

Life-membership.

On graduation, students should be given life membership in their club or clubs. This would entitle them to consult the university experts, and to receive, test, report on, and utilise new lines coming out of their club(s) for the rest of their lives. They would also be encouraged to donate some of their best lines to the university club, and to attend club meetings.

Start new breeding clubs.

Having returned to their family farm, or arrived at their new place of work, graduates would be encouraged to start one or more new breeding clubs among farmers and other interested parties. This would lead to a proliferation of breeding activity. Their knowledge of breeding for horizontal resistance, as well as their life memberships in their university club(s) would be valuable assets in these activities.

Advantages for the professors

A new approach to teaching.

Plant breeding clubs would provide a new kind of teaching in which the students themselves are involved in the actual achievements of both demonstrating the value of horizontal resistance, and of producing new resistant cultivars.

Teaching credits.

Each club would have a professor in charge of it and the professor would earn teaching credits for this activity.

Long-term research.

Short-term research grants have no guarantee of renewal and our system of financing agricultural research discourages long‑term research projects, such as breeding for horizontal resistance. Because the breeding club work would be a teaching activity, its continuation would be secure, and the professor in charge could undertake long-term research in this topic. It need hardly be added that this is an area that has been seriously neglected, and that such research is urgently needed. In no small measure, this neglect has been due to the long-term nature of the research, and the insecurity of the research grant system.

Advantages for amateur breeding clubs

A scientific basis for amateur breeders.

Amateur breeding clubs that were initiated by a graduate with membership in his university club(s) would have the advantage of doing breeding that was technically sound. Their members could proceed with confidence.

Overcome intimidation.

Such a club would be the best method of over‑coming the intimidation that discourages an inexperienced amateur.

Rewards.

The club could provide very considerable rewards for its members. These include a sense of achievement, improved new cultivars for farmer-members, breeders’ royalties, and the satisfaction of participating in a successful communal activity.

Advantages for the university

A new approach to teaching.

In addition to the learning process, plant breeding clubs would provide advantages that the students would not obtain from the more conventional lab and field classes. These advantages include the actual participation in the production of new cultivars, and life membership in the club. Members of existing clubs have also discovered that their clubs provide a useful link between their practical experience on their family farm, and the relatively academic teaching of the university.

A new approach to research.

Most universities have abandoned research that involves plant breeding designed to produce new cultivars. Plant breeding clubs would provide new opportunities for providing farmers with the practical assistance that emerges from successful research.

Prestige from successful new cultivars.

The production of an assortment of valuable new cultivars in a range of locally important crops could provide valuable prestige for a university.

A renewal of the land-grant college concept.

The prestige earned from new cultivars would represent a return to the esteem that existed when the land grant colleges were first formed in the United States, with a really close co‑operation between agricultural scientists and farmers.

Advantages for the local farmers

Farmer-participation in research.

Institutional plant breeding has become so esoteric that farmers cannot understand it. Nor can they participate in it. Farmers should be encouraged to form their own clubs, assisted, no doubt, by some of their children who have graduated from a university that had plant breeding clubs. Equally, a university club might do well to instruct a few farmer-members who would themselves provide practical input.

Greatly increased breeding activity.

One of the chief criticisms of institutional and corporate plant breeding is that their work is so expensive, and that they are so specialised, and so technical, that their total breeding output is severely limited. A multiplicity of plant breeding clubs would provide a greatly increased amount of plant breeding.

Constructive competition between many breeding clubs.

If there were many plant breeding clubs, operated both by universities and farmers themselves, there would be constructive competition that would lead to an abundance of competing cultivars with gradually improving horizontal resistance to all locally important pests and diseases, as well as improving yield, quality of crop product, and agronomic suitability. This competition would continue until a ceiling was reached, when little further progress would be possible.

Cultivars suited to local agro-ecosystem.

These competing cultivars would all be the result of on-site selection in the local agro-ecosystem. They would be well balanced with all the variables in that agro-ecosystem.

Wide choice of new cultivars.

An abundance of good cultivars would give both farmers and consumers a wide choice of cultivars.

Freedom from the hazards, labour, and cost of pesticides.

Once adequate horizontal resistance had been accumulated, farmers would be freed from the environmental and human hazards, as well as the labour and costs of applying crop protection chemicals.

Reduction of crop losses.

As horizontal resistance accumulated, the crop losses from pests and diseases would decline.

Reduction of biological anarchy.

As horizontal resistance accumulated, the biological anarchy that was induced by crop protection chemicals would decline, as biological control agents returned and increased in numbers.

Cumulative crop improvement.

Because a good horizontally resistant cultivar need never be replaced, except with a better cultivar, breeding for horizontal resistance is cumulative and progressive. The overall effect of plant breeding clubs, therefore, would be a cumulative crop improvement.

Advantages for the environment

A return to resistance breeding.

Plant breeding clubs would lead to a return to the resistance breeding that was taken for granted before 1900.

Exponential increase in plant breeding expertise and activity.

Plant breeding clubs would lead to an exponential increase in the total plant breeding expertise and activity. This increase would be comparable to the exponential increase that we are witnessing now in both computer literacy and the use of the Internet.

Widespread reduction in pesticide use.

There would also be a widespread reduction in the use of crop protection chemicals, with a corresponding reduction in health and environmental hazards.

Improved bio-diversity.

An abundance of competing cultivars would provide a greatly improved bio-diversity. This diversity would occur between crops rather than within crops. Nevertheless, it is fundamental ecological principle that diversity provides stability.

Economic benefits

Cost of pesticides reduced.

The cost of crop protection chemicals, now running into billions of dollars annually, would be greatly reduced and, in some corps, largely eliminated.

Cost of pesticide application reduced.

The same is true of the costs of application of crop protection chemicals.

Crop losses reduced.

The pre-harvest crop losses from parasites average more than 20%, worldwide, in spite of the use of crop protection chemicals. These loses could be greatly reduced by the proper use of horizontal resistance.

Increased yields of a cheaper and healthier product.

The overall effect of a multiplicity of plant breeding clubs would be improved yields of crop products that were both cheaper to produce and healthier for the consumers.

Advantages for overseas aid organisations

New assistance technique.

Plant breeding clubs could provide an entirely new technique for overseas aid in agriculture. Overseas aid organisations could initiate these clubs in Third World universities, and support them with technical and financial assistance until they could stand on their own feet. If successful, these clubs could eventually prove to be the most effective agricultural assistance technique of them all. Overseas aid is often sub-divided into ‘soft’ and ‘hard’ aid. Soft aid consists or studies and research that result in advice and reports that are soon neglected and forgotten. Hard aid results in new physical entities that make a very real contribution to welfare, such as new roads, schools, or systems of communication. New, improved cultivars constitute hard aid.

Inexpensive technique.

These clubs could also prove to be one of the least expensive techniques of overseas aid.

Plant Breeding Clubs

Learning how to breed plants for horizontal resistance is similar to acquiring computer literacy. Initially, for older people at least, it is somewhat intimidating, and it requires ‘hands-on’ experience. But, as this experience is gained, the new activity is quickly discovered to be easy, enjoyable, and useful. Plant breeding clubs will require a modicum of technical assistance from scientists, and they might even include scientists among their members. But, in general, these clubs would be made up of amateur breeders, and they would be totally free to breed any crop they choose, using any techniques they choose, to achieve any objectives they choose.

We can recognise two kinds of plant breeding club designed to promote horizontal resistance. A private club consists of a group of amateur breeders, such as farmers, hobby gardeners, environmentalists, or green activists. The second kind of club is primarily educational, and is the university club, which differs only in that it is made up of students, who are supported by their university. The possibility of secondary school clubs and 4H clubs should also be considered.

Perhaps the most important feature of university clubs is that graduates can be given life-membership in their club, or clubs. Once they had returned to their family farms, or become agricultural scientists, these graduates should be entitled to propagating material of the potential new cultivars coming out of the club, for the rest of their lives. After one or two decades, there would be hundreds, perhaps thousands, of club alumni, organising new clubs, and testing and exchanging new lines with their university clubs, in the appropriate agro-ecosystems. These alumni would also be entitled to technical assistance from their old university club. These privileges would permit widespread farmer-participation in research. And a number of competing universities would provide farmers with the widest possible choice of cultivars.

University plant breeding clubs

A special feature of university clubs is the university ambience. Students are far more likely than amateurs to overcome the intimidation, and the initial hesitation about breeding crops for horizontal resistance. The students would do all the work of breeding, supervised and guided by a professor. This would provide them with the initial ‘ice-breaking’ and the essential ‘hands-on’ experience. The students would earn course credits from their club membership, and their teacher would earn teaching credits.

The main function of university breeding clubs is to teach. This teaching will promote a widespread proliferation of breeding clubs. Graduates, with life membership in their clubs, will most likely return to their family farms, or become agricultural scientists. If they become farmers, they might initiate one or more farmers’ breeding clubs in their own locality. If they become scientists, they might initiate one or more private breeding clubs among concerned amateurs in the vicinity of their work. Or they may become entrepreneurs themselves, relying on breeder’s royalties to earn a living.

In any event, both the concept and the practice of plant breeding clubs will begin to spread. As increasing proofs of the viability of horizontal resistance, and the ease and usefulness of amateur breeding, begin to accumulate, the proliferation of clubs will increase. The public interest in pure food, and a clean environment, to say nothing of the farmer interest in high yields and cheap production, is so strong that the process of growth and proliferation will increase exponentially.

That these developments have not occurred before now is due to a lack of knowledge. No member of the public was even aware of this possibility. The professional plant breeders, in their breeding institutes, have had no interest in promoting either amateur breeding or horizontal resistance. Indeed, they genuinely believed both to be impractical, if not impossible. And the chemical corporations, with their concept of crop protection chemicals substituting for host resistance, have also had no interest in promoting horizontal resistance.

The Advantages of University Breeding Clubs

The advantages of plant breeding clubs, particularly university clubs, over institutional and corporate plant breeding, are so marked that they merit emphasis.

Advantages for the students

Overcome the initial intimidation. For anyone who has not tried it before, the very thought of plant breeding is somewhat intimidating, in the same way that the first use of a computer, or the first dive into deep water, is intimidating. Once this intimidation is overcome, plant breeding for horizontal resistance turns out to be very easy, and very rewarding. The ambience of a university breeding club is undoubtedly the best way of overcoming this intimidation, but this comment should not discourage other amateurs from starting their own clubs.

Learning to breed for horizontal resistance. The use of computers cannot be learned from manuals, and ‘hands-on’ experience is essential. The techniques of breeding for horizontal resistance also require ‘hands-on’ experience and a breeding club is the best means of providing such experience. The students themselves would do all the work of breeding and they would gain practical experience in every aspect of the breeding process.

Improved participation and interest. Many agricultural students, who grew up on a farm, find there is a gap between their own farming experience and the somewhat academic teaching within the university. A breeding club closes this gap very effectively, and it demonstrates the practical utility of scientific concepts. The club also provides students with active participation, and a sense of achievement, as alternatives to passive learning.

Earn course credits. As one of the inducements to join, students should earn course credits from their breeding club membership and participation.

Life-membership. On graduation, students should be given life membership in their club or clubs. This would entitle them to consult the university experts, and to receive, test, report on, and utilise new lines coming out of their club(s) for the rest of their lives. They would also be encouraged to donate some of their best lines to the university club, and to attend club meetings.

Start new breeding clubs. Having returned to their family farm, or arrived at their new place of work, graduates would be encouraged to start one or more new breeding clubs among farmers and other interested parties. This would lead to a proliferation of breeding activity. Their knowledge of breeding for horizontal resistance, as well as their life memberships in their university club(s) would be valuable assets in these activities. 

Advantages for the professors

A new approach to teaching. Plant breeding clubs would provide a new kind of teaching in which the students themselves are involved in the actual achievements of both demonstrating the value of horizontal resistance, and of producing new resistant cultivars.

Teaching credits. Each club would have a professor in charge of it and the professor would earn teaching credits for this activity.

Long-term research. Short-term research grants have no guarantee of renewal and our system of financing agricultural research discourages long-term research projects, such as breeding for horizontal resistance. Because the breeding club work would be a teaching activity, its continuation would be secure, and the professor in charge could undertake long-term research in this topic. It need hardly be added that this is an area that has been seriously neglected, and that such research is urgently needed. In no small measure, this neglect has been due to the long-term nature of the research, and the insecurity of the research grant system.

Advantages for the amateur breeding clubs

A scientific basis for amateur breeders. Amateur breeding clubs that were initiated by a graduate with membership in his university club(s) would have the advantage of doing breeding that was technically sound. Their members could proceed with confidence.

Overcome intimidation. Such a club would be the best method of over-coming the intimidation that discourages an inexperienced amateur.

Rewards. The club could provide very considerable rewards for its members. These include a sense of achievement, improved new cultivars for farmer-members, breeders’ royalties, and the satisfaction of participating in a successful communal activity.

Advantages for the university

A new approach to teaching. In addition to the learning process, plant breeding clubs would provide advantages that the students would not obtain from the more conventional lab and field classes. These advantages include the actual participation in the production of new cultivars, and life membership in the club. Members of existing clubs have also discovered that their clubs provide a useful link between their practical experience on their family farm, and the relatively academic teaching of the university.

A new approach to research. Most universities have abandoned research that involves plant breeding designed to produce new cultivars. Plant breeding clubs would provide new opportunities for providing farmers with the practical assistance that emerges from successful research.

Prestige from successful new cultivars. The production of an assortment of valuable new cultivars in a range of locally important crops could provide valuable prestige for a university.

A renewal of the land-grant college concept. The kudos earned from new cultivars would represent a return to the esteem that existed when the land grant colleges were first formed in the United States, with a really close co-operation between agricultural scientists and farmers.

Advantages for the local farmers

Farmer-participation in research. Institutional plant breeding has become so esoteric that farmers cannot understand it. Nor can they participate in it. Farmers should be encouraged to form their own clubs, assisted, no doubt, by some of their children who have graduated from a university that had plant breeding clubs. Equally, a university club might do well to instruct a few farmer-members who would themselves provide practical input.

Greatly increased breeding activity. One of the chief criticisms of institutional and corporate plant breeding is that their work is so expensive, and that they are so specialised, and so technical, that their total breeding output is severely limited. Hence the need for the ‘big space and high profile’ of vertical resistance breeding. A multiplicity of plant breeding clubs would provide a greatly increased amount of plant breeding.

Constructive competition between many breeding clubs. If there were many plant breeding clubs, operated both by universities and farmers themselves, there would be constructive competition that would lead to an abundance of competing cultivars with gradually improving horizontal resistance to all locally important pests and diseases, as well as improving yield, quality of crop product, and agronomic suitability. This competition would continue until a ceiling was reached, when little further progress would be possible.

Cultivars suited to local agro-ecosystem. These competing cultivars would all be the result of on-site selection in the local agro-ecosystem. They would be well balanced with all the variables in that agro-ecosystem.

Wide choice of new cultivars. An abundance of good cultivars would give both farmers and consumers a wide choice of cultivars.

Freedom from the hazards, labour, and cost of pesticides. Once adequate horizontal resistance had been accumulated, farmers would be freed from the environmental and human hazards, as well as the labour and costs of applying crop protection chemicals.

Reduction of crop losses. As horizontal resistance accumulated, the crop losses from pests and diseases would decline.

Reduction of biological anarchy. As horizontal resistance accumulated, the biological anarchy that was induced by crop protection chemicals would decline, as biological control agents returned and increased in numbers.

Cumulative crop improvement. Because a good horizontally resistant cultivar need never be replaced, except with a better cultivar, breeding for horizontal resistance is cumulative and progressive. The overall effect of plant breeding clubs, therefore, would be a cumulative crop improvement.

Advantages for the environment

A return to resistance breeding. Plant breeding clubs would lead to a return to the resistance breeding that was taken for granted before 1900.

Exponential increase in plant breeding expertise and activity. Plant breeding clubs would lead to an exponential increase in the total plant breeding expertise and activity. This increase would be comparable to the exponential increase that we are witnessing now in both computer literacy and the use of the Internet.

Widespread reduction in pesticide use. There would also be a widespread reduction in the use of crop protection chemicals, with a corresponding reduction in health and environmental hazards.

Improved bio-diversity. An abundance of competing cultivars would provide a greatly improved bio-diversity. This diversity would occur between crops rather than within crops. Nevertheless, it is fundamental ecological principle that diversity provides stability (see 1.14). 

Economic benefits

Cost of pesticides reduced. The cost of crop protection chemicals, now running into billions of dollars annually, would be greatly reduced and, in some corps, largely eliminated.

Cost of pesticide application reduced. The same is true of the costs of application of crop protection chemicals.

Crop losses reduced. The pre-harvest crop losses from parasites average more than 20%, worldwide, in spite of the use of crop protection chemicals. These loses could be greatly reduced by the proper use of horizontal resistance.

Increased yields of a cheaper and healthier product. The overall effect of a multiplicity of plant breeding clubs would be improved yields of crop products that were both cheaper to produce and healthier for the consumers.

Advantages for overseas aid organisations

New assistance technique. Plant breeding clubs could provide an entirely new technique for overseas aid in agriculture. Overseas aid organisations could initiate these clubs in Third World universities, and support them with technical and financial assistance until they could stand on their own feet. If successful, these clubs could eventually prove to be the most effective agricultural assistance technique of them all. Overseas aid is often sub-divided into ‘soft’ and ‘hard’ aid. Soft aid consists or studies and research that result in advice and reports that are soon neglected and forgotten. Hard aid results in new physical entities that make a very real contribution to welfare, such as new roads, schools, or systems of communication. New, improved cultivars constitute hard aid.

Cheap technique. These clubs could also prove to be one of the cheapest and most effective techniques of overseas aid.