A Plea for Agriculture
Without Poisons

by José A. Lutzenberger - December 1995
Strengthening Crops Instead of Fighting Pests
(translation from the original German)


Until the turn of the century, traditional peasantry constituted an economically self-sufficient food production and distribution system, producing its own inputs: its own fertilisers, energy and seed. Those tools and implements that were not made by the peasants themselves were made by village craftsmen. Most produce was sold at weekly markets. This system still largely prevailed during the years of hardship after 1945. In Germany it gave townspeople the possibility to barter for food in the countryside. In a similar crisis today the farmers themselves would also have to barter for food, but where?

In the last few decades, industry has succesfully taken over from agriculture most of its tasks. Most farmers were thereby forced to give up, this trend is not yet over. All that is left to farmers is that part of the work that carries the greatest risks - tractor driving, applying fertilisers and spraying poisons and, of course, the risks associated with poor harvests, rising costs of inputs and falling prices for produce.

Modern agricultural methods were neither invented nor asked for by the peasantry, but were promoted by industry in its own interest. Industry has succeeded in imposing its philosophy on agricultural schools and colleges and research establishments. Where it fails to control public agricultural extension, it advises farmers directly.

This led to the exaggerated use of poisons. Thus, a peculiar dogma became established according to which it is only possible to farm efficiently and profitably if the enemies of our crops are fought with poisons. Only in this way, the litany goes, can we still manage to feed the earth's relentlessly multiplying billions of hungry mouths. In fact, this is an absurd idea, poisons and food don't belong together at all.

Pests - whether insects, mites, nematodes, fungi, bacteria or even viruses, are presented as arbitrary and virulently hostile enemies. Warning services have been set up to give farmers advance notice of impending attack. Spraying schedules have been devised recommending preventive pesticide application to ward off attack by whatever possible pests. Indeed, the appearance of a pest is not even awaited - a toxic battlefield already anticipates the culprit.

But pests are not arbitrary enemies. If that were the case, all life on our planet would have ceased long ago, after all, no life form is without its parasites or predators. Aphids, for example, have existed for 300 million years, ample time for them to have wiped out their host plants and themselves in the process.

The fact that aphids have natural enemies does not adequately explain why this has not happened. There is more to the story. Close observation shows, again and again, that healthy aphid populations can grow rapidly even in the presence of natural predators, such as syrphis flies or ladybirds and can also collapse suddenly in their absence. Fungal, bacterial and viral diseases can spread and collapse within a short time span, even on one and the same plant.

But pest are not arbitrary enemies. They should be seen as indicators showing that all is not well with the plant. Many other important factors enter into this. For example, it is frequently observed that the potato beetle will leave alone an organically grown potato patch while the adjoining field which has been conventionally managed with chemicals is totally infested and can be saved only by further spraying.

Francis Chaboussou, a French biologist at the agricultural research centre (Institut National de la Recherche Agronomique) in Bordeaux conducted field and laboratory trials over many years and established that a plant's susceptibility or resistance to pests and diseases depends on the state of equilibrium of its metabolism. Only those plants with unbalanced nutrition are prone to attack, Chaboussou formulated the theory of TROPHOBIOSIS (nutrition theory). As far as I know this very important treatise has not yet found its way into the English language.

The book originally appeared in French under this title:

Francis Chaboussou
Santé des Cultures, Une Révolution Agronomique
Flammarion, La Maison Rustique
Paris, 1985,
ISBN 2-7066-0150-7

Unfortunately this book is difficult for laypersons since a basic familiarity with chemistry is assumed. Likewise the reader needs familiarity with the technical details of chemical crop protection. Few people have read this book and the various schools of organic farming have not grasped its monumental importance, with the result that the chemical industry has not needed to bother to defend itself against it. It has simply ignored it, in stark contrast to the rumpus stirred up in the early 1960's by Rachel Carson's book "Silent Spring". Rachel Carson came in for outrageous attack.

According to the theory of trophobiosis, pests starve to death on healthy plants. In order for them to thrive on host plants, the sap in the cell must contain an excess of water-soluble nutrients. Pest organisms are unable to utilise foreign protein directly for their nourishment since they have no proteolitic enzymes, that is, the enzymes necessary for the breakdown of proteins. They must be able to obtain enough amino acids, the building blocks of which proteins are made. The sap must also contain sugar instead of insoluble starch and vital minerals. When these requirements are met, and provided that the artificially high concentrations are maintained, the pests can build their own species-specific proteins and multiply rapidly.

Healthy plants are either in a state of winter rest (hybernation) or summer rest (estivation) in arid areas, when the biochemical processes in the cell are quiescent, or they are growing vigorously. This is a time of intensive metabolic activity. As soon as amino acids, sugars and minerals are produced they are used up in proteosynthesis. The level of these substances in the cell thus remains low and is inadequate for pests which either starve or, at most, fail to multiply. Usually pests avoid plants in this state: they just don't taste good!

How does a congestion of amino acids, sugars and minerals occur in the cell sap? There are two possibilities:

  1. Protein synthesis is inhibited, or partially inhibited.

  2. Amino acids are produced in the cell sap faster than they can be incorporated into new proteins.

What conventional farmer or agronomist has not noticed that the more pesticides they use, the more pest problems they have? Not only do old pests become more destructive but new ones appear as well. Before the massive use of poisons in agriculture in the 1950's, mites (red spider) were rarely a problem. Bacterial and viral diseases were similarly exceptional.

Chaboussou showed that agripoisons, even when declared "contact pesticides", always penetrate into the plant and do have an effect on its metabolism. It can be compared to sand in a gear. Even where the action is comparatively mild it can severely inhibit protein synthesis and lead to congestion of amino acids. Thus, herbicides, fungicides, insecticides, nematicides, etc. can actually invite attack of pests and disease organisms.

Unbalanced application of mineral fertiliser can also inhibit vital processes. In modern agriculture we feed our crops with highly concentrated, mostly water-soluble salts. They are often drilled in with the seed. The seedling thus gets too much and too little is left for the grown plant. In both circumstances metabolism is disturbed.

Plants may often suffer from lack of certain trace elements even when these are abundantly present in the soil. This may be brought about by impoverishment of the soil fauna and flora through depletion of humus and is exacerbated by use of poisons. An example is that of chlorosis (an iron deficiency) in vineyards where the soil contains enough iron but where severe soil compaction by heavy machinery and/or the near complete disappearance of soil organisms prevents its uptake by the plant. The chemical industry offers iron chelates for spraying on the leaves. In this way disease is first encouraged, followed by the sale of a drug to cure it. Deficiency in trace elements also disturbs protein formation.

And what is the cause of excess amino acids in the cell? Massive application of nitrogen fertilisers, particularly ammonium salts, such as ammonium sulphate, ammonium nitrate, calcium ammonium nitrate, diammonium phosphate, urea, and others forces overproduction of amino acids in the plant. Overfertilisation with chicken manure which is rich in urea, another ammonium compound has the same effect. Since the amino acids cannot all be used fast enough they accumulate.

This build up can be without visible symptoms. As an analogy, think of a multi lane motorway. A small bottleneck can cause a mile-long tail-back, but beyond this bottleneck traffic flows normally. It is usually impossible to tell exactly what happened. It may only have taken one driver to touch his brakes briefly. Thus an afflicted plant can appear quite normal and the only way to show that there is an excess of amino acids is by analysis. An analogy for the opposite effect is the end of the game at the big football stadium. Too many cars try to get onto the motorway at the same time, getting in each other's way. The road cannot handle it fast enough.

Chaboussou's insights are of revolutionary importance. They challenge the fundamental postulates of chemical crop protection. Even many organic farmers often still regard pests as arbitrary enemies, the only difference being that they attempt to substitute more benign methods of control and to check pests by introducing their natural predators.

From this it is clear that the aim must not be to develop increasingly potent weapons against a never-ending procession of new and ever more resistant pests. Rather, we must learn to manage our fields in such a way that our crops receive a balanced supply of nutrients and their metabolism remains undisturbed. This can only be achieved on a living soil. Up until the end of the 1940's agricultural teaching and research was still firmly in this direction. This approach was not abandoned for scientific reasons, it presuposes more and deaper science. The war with poisons is based on undisguised empiricism - clobber it, and see what happens! I spent a decade and a half working for a large chemical corporation and witnessed at first hand how agripoisons are developed. It has little in common with real science. In most cases it is a purely business proposition in patentable commercial products.

Those of us promoting organic agriculture, more often than not, must work with idealism for no economic gain. By contrast, patented products - as well as unpatented products that require large factories, such as chemical fertilisers and machinery - enable huge techno-bureaucratic structures to be built up.

For this reason, powerful interests are now lobbying parliaments the world over to pass legislation to make it possible to patent living organisms, even parts of them right down to individual genes. It is the very same multinational corporations that grew powerful with their agripoisons that are now promoting the use of patented genetically engineered seed, thus depriving the surviving farmers of their last bit of independence. Some of this new seed comes pelletised with chemical fertiliser, insectiside, fungicides and with a total herbicide. The breeding of the new patented cultivars is not for more resistance to pests, but for resistance to the company's own herbicide...

The methods of modern agriculture almost always harm or virtually erradicate soil life. As soil flora and fauna perish, the business with agripoisons booms. At the beginning, those who promoted agripoisons did not see this connection. They were happy that pests were growing more numerous. Now their survival depends on it.

Farmers must become aware that modern agricultural methods have little to do with genuine technological progress but a great deal with creating dependency.

The best proof that something is very wrong with agriculture today is the farmers' income. According to the German Federal Statistical Office (1991) the average real disposable income per member of a farmer's household, at DM 14,500.-- is the third lowest after factory workers, just above unemployed and people on welfare benefit. What sort of economic system rewards so poorly the most important activity for society's survival - working hand in hand with Creation to secure food and preserve a healthy landscape? Surely this says something about the quality of today's agriculture.

This process must be reversed. It means the adoption of organic soil management, minimal tilling, no more deep ploughing, direct drilling. The soil must be protected at all times with a living or non-living ground cover. Weeds can be kept in check by appropriate crop rotations or, as in orchards, in vineyards and hop fields, with an appropriate green cover that should always include legumes.

Only in humus-rich soils can mycorrhizae help plants absorb the necessary trace elements. Mycorrhizae are biological communities of certain fungi and bacteria that become established symbiotically on the plant rootlets. These living complexes can extract trace elements directly from rock particles in the soil. Mycorrhizae, together with free-living bacteria and fungi, small animals like springtails, even larger ones like earthworms, also promote the absorption of fixed phosphorous, as well as of potassium, calcium and magnesium.

In humus-rich soil, this dispenses with the need for expensive water-soluble phosphates, such as super and triple superphosphate. It makes the even more expensive forms of phosphorus, like those contained in complex fertilisers, totally superfluous. Cheap raw phosphate is all that is needed, and little enough of that since most of the soils in the First World contain enough phosphorus for decades to come, due to over-application in the past. Phosphorus is not leached out, but can only be reduced through loss by soil erosion. Organic soil management can take advantage of phosphorus chemically fixed in the soil which is not available to conventional soil management and that does not appear in conventional soil analysis.

And why should farmers buy expensive nitrogen from industry when in healthy soils bacteria in the roots of legumes (Rhizobia) and free-living bacteria such as Azotobacter are able to fix nitrogen from the air? What is more, they do so at normal temperatures and pressures. Industry, by contrast, achieves this by means of the costly Haber-Bosch process, involving high pressures and temperatures with exorbitant consumption of energy. All that the bacteria require is a small fraction of the solar energy that the plant captures and supplies to them through its roots or that is stored in the soil humus. In addition, they supply it to the plant slowly and continuously, thus preventing any metabolic disturbances.

Our conventional fertilising practices thus are one of the basic reasons for the increase in pest attacks. The highly concentrated, mainly water-soluble salts of commercial chemical fertilisers severely interfere with the sensitive and complex biochemical processes in the soil. They should therefore be avoided as far as possible and replaced by water-insoluble mineral fertilisers such as raw phosphate and rock powder. Where feasible, organic fertilisers, compost or mulch, should be used. If truly organic soil husbandry is practiced, humus will form without the aid of added organic matter. However, the most practical way is a diversified agriculture which incorporates animal husbandry.

If plant health is restored through soil health, poisons can be dispensed with altogether. Only substances that strengthen and stimulate plants, and which are completely harmless to people, need be used. Herbicides are in any case irrelevant to an agriculture that promotes a diversity of living plants.

I would like to introduce some concrete examples. In my home region, southern Brazil, there are apple growers who produce delicious apples, despite the fact that apples are difficult to grow and the climate is not ideal. Normally apples are among the most heavily sprayed crops. These farmers spray with a "substance" that they make themselves. It costs nothing more than some thought and a small amount of work. It is similar to mature biogas slurry and is made in open drums during the summer according to the following recipe:

Place 50 kg of fresh cow manure in a 200-litre drum. Fill with water. Stir in a few kilograms of sugar or molasses and wood ash, plus a little lime. For even better results add various trace elements such as zinc, manganese, copper, boron, cobalt, molybdenum and iron. Leave the brew to mature for about 1 month at temperatures over 20ş C. The biogas escapes into the air. Then dilute the matured brew in the ratio of 1 to 5 parts in 100 parts of water. Spray on to the apple trees once every week or two, depending on the weather. The fruit fly is baited by molasses, although it rarely attacks healthy trees. During the winter, apply a solution of lime to the trunks. The costs are roughly 10% of those of conventional apple growers, and the apples keep better. Once, while travelling in Tyrol, I heard that formerly peasants used to apply a slurry to their apple trees! Organic farming isn't expensive, it is in fact cheaper than conventional farming. What is required is a little thought that dispenses with blind reliance on pre-packaged formulae. It is interesting to note how official agricultural extension agents and agricultural research workers often refuse even to visit such orchards.

Another example is also from my home region. Guava is a native fruit from Brazil that Europe imports from South Africa. A large fruit grower who raises guavas has been following my recommendation for the past 15 years. On an industrial scale operation (65 hectares with 28,000 trees) he produces about 1000 tons of fruit per year. He sprays every two weeks with whey diluted 1:5 or 1:10 in place of fungicides. Yes, whey from cheese making! The trees develop dark green leathery leaves, the fruit is flawless and delicious. A tank truck of whey costs him as much as a single cannister of fungicide used to.

He has given up using agripoisons completely. Fruit flies, which are now only a minor nuisance and becoming less, are baited with molasses. Ground cover is kept short by grazing sheep, sometimes cattle. A similar, but larger fruit farm next door was on the point of giving up as agrichemicals were getting too expensive. Now it also is switching to organic farming.

It is probable that the use of whey will also make fungicides in hop and vinyards superfluous. We have discovered that milk, diluted 1:10 or 1:20 works well against mites, even on conventionally grown fruit. In any case, giving up modern fungicides prevents mite infestation.

In the state of Rio de Janeiro, the majority of pineapple growers are substituting a dilution (1:10) of cow urine to the conventional fungicides, also with excellent results. The fruits are both tastier and keep better. A ravishing fungus disease in cocoa plantations is now also under perfect control with the application of highly diluted cows urine. Official research is now recommending its use in coffee plantations.

Organic methods quickly produce healthy plants in coffee, cocoa and citrus plantations. It is possible to do entirely without fungicides and insecticides and the ground cover can be kept short by grazing sheep.

More examples could be added, but it is the basic principle that is important. The organic substances applied are not weapons against pest attack but act through strengthening the plants and stimulating protein synthesis. This makes the plants unattractive to pests.

In my firm, "Vida Produtos Biológicos Ltda." we make a humus concentrate with added trace elements from the sludge of a pulp mill. This product produces splendid results on almost all crops when applied to the leaves in very diluted form. It is effective not only in the field but also in orchards and vegetable gardens, as well as on flowers in the greenhouse. Orchid growers are delighted with the exuberant root growth and splendid blossoms.

I cannot avoid the impression that due to vested interests, biogas has, in Germany, been researched to death in that one considered only the energy and both neglected and disposed of the matured slurry. For years we have observed that biogas slurry, well matured, works spectacularly when applied directly to the soil or, in dilution, on the leaf. Poisons become wholly unnecessary!

The range of harmless alternative substances is large: biogas slurry, humus extract, whey, milk, yoghurt, amino acids, blood, horn, herbal extracts, rock powder, lime, bentonite, ash, waterglass, and much else.

It is in these directions that one now needs intensive experimentation, but by the farmers themselves. If we wait for the official bodies to do this for us we will have long to wait. The industry will probably try to apply only those of these findings that can lead to patented products, to be sold profitably.

Of course there can also be failures, but less often than in chemical agriculture. A plant's metabolism can also be affected by climatic shock. Unfortunately, we have no answer to this kind of problem. For example, one sees occasional generalised attack by moths in European forests. Years ago, at a time when the ozone hole was very pronounced in the Southern Hemisphere, leaf-cutting ants attacked native cactus plants at our estate, Gaia Corner, in such a way that only a skeleton of thorns was left. Normally, the ants circulate freely among and over them without doing any harm.

If the uprooting of peasants is to be reversed, we must restore agriculture to biological health. Only then will it also become economically sustainable for the family farm to survive.

Wide ranging change is necessary. We cannot afford to solve the problem by waiting while a few dozen, even a few hundred, farms convert to pure 100% biological methods, following one or another of the established schools of organic farming. It would take far too long. Moreover, quick and complete conversion is too risky for a farmer who is up to the neck in problems. However, a gradual decrease in the use of expensive chemical inputs represents a growing saving that will lead to economic survival.

Complete conversion to regenerative agriculture must be achieved little by little, in small successive steps. Much more will be achieved ecologically and socially if hundreds of thousands of farms use successively less poisons and chemical fertilisers, even if initially the reduction is only a few percent.

We must find ways that from now on lead us consciously in that direction. Only then can we achieve healthy agriculture and clean food.

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