Francis Chaboussou, the French biologist and researcher at the Agricultural Research Institute in Bordeaux, France, has over many years of observation, both in the field as well as in the laboratory, found out how the resistance or the vulnerability of plants to pest attacks is determined by how balanced the metabolism of the plant is. He formulated his Theory of Trophobiosis (translated as "nutrition biology"). He demonstrated and proved Trophobiosis through the results of his practical experiments. He discuses this in his book ‘Plant health and how it is affected – the detrimental influence of synthetic fertilisers and plant protection agents’.

The theory of trophobiosis says: "A pest starves on a healthy plant". For the pest to thrive on a host plant, there has to be an oversupply of water-soluble nutrients in the fluids of the plant. It is not possible for the pests to feed directly off foreign proteins because they do not possess any proteolytic enzymes (protein splitting enzymes). They have to find in the sap of the plant sufficient amino acids. There also have to be sugars present instead of the water insoluble carbohydrates as well as the necessary minerals. Then they can build up their own species-specific proteins used to multiply themselves quickly – but only as long as the unnaturally high content of amino acids, sugars, and minerals do not decline.

When the plant is growing actively, we will find an intensive metabolism in the cell fluids. The amino acids, the sugars and minerals will be utilised in the build-up of new proteins at the same rate as they get manufactured. The cell fluid therefore is fairly poor in excess of these substances. These are certainly not enough for the pest, it starves or it may just survive but can’t multiply. In most instances a pest will not visit a plant in such a state, the plant is not attractive, not ‘tasty’ to the pest.

When do we find congestion of amino acids, sugar and minerals in the cell fluids? There are two possibilities:

1. When Proteosynthesis,(the building up of new proteins) is inhibited, even if only partially.
2. When there are more amino acids ‘delivered’ to the cell fluid than can be built into new proteins.

Any observant conventional farmer has observed that the more he uses agro chemicals the more problems with pests and diseases appear. Prior to the massive use of agrochemicals beginning in the 1950’s mites were hardly a problem and disease produced by bacteria and viruses were an exception.

Chaboussou has shown that agrochemicals even when they are so-called contact poisons always enter into the plant and influence the plants’ metabolism. Even with minimal effect it can lead to delicate inhibitions in proteosynthesis, consequently to a congestion of amino acids. So the use of herbicides, fungicides or acaricides (poisons against spider mites) can lead to the occurrence of pests, can trigger insect attacks and /or other diseases.

In modern industrial agriculture, crops are fed highly concentrated, mostly water soluble, salts as fertilisers. They are often applied in the seed drill. So the young plant has first too much and then too little nutrient. In both cases the metabolism of the plant is disturbed.

Destruction of the life of the soil through humus reduction and the use of poisons applied often leads to the plant suffering from a shortage of trace elements even if those elements are present in the soil. A good example is the lack of iron in vineyards. Often there is enough iron in the soil but the compaction of the soil through heavy machinery and / or the disappearance of the soil life obstructs the taking up of iron by the plant The industry then offers iron chelates to be applied to the leaf. First they aid the establishment of diseases and then they sell you the medication! A lack of trace elements also leads to a disturbed building up of proteins.

What contributes to an excessive production of amino acids in the cell fluid? When we apply massive amounts of nitrogenous fertilisers (artificial or even raw chicken manure) then we basically force the plant to an overproduction of amino acids. There are such quantities of amino acids available that the proteosynthetic process cannot handle them. Thus we create congestion within the cell. One does not necessarily see this congestion in the plant. A plant can look completely normal and only through analysis of the cell fluid will one detect a blockage, congestion, and an excess of amino acids.

The findings of Chaboussou are of tremendous importance. They refute / disprove the basic assumptions of the chemical plant protection / agrochemical industry. Often organic farmers still have the picture of the pest / disease as arbitrary enemies and only want to get rid of them through less harmful chemicals, preparations or by natural enemies of the pest.

We should not be concerned to develop new chemicals against more and more resistant pests, but we must learn to work in such a way that our plants receive a balanced nutrition, through fertile soils, and then we will not get disturbances in their metabolism. This is only possible in a living, healthy soil whose basis is its organic matter content.