The Pest and Pathogen Carousel

Tuesday, November 7, 2017

I’m reading a book by Francis Chaboussou called “Healthy Crops.” The book has groundbreaking material, and all growers should give it a read. I would compare Chaboussou (although much less known) to Liebig, the German chemist who made major contributions to agriculture and biological chemistry and was considered the founder of organic chemistry. Chaboussou presents ideas that on reflection make a good deal of sense.

Chaboussou’s thesis suggests that almost all conventional chemical agricultural technologies create favorable conditions for the growth of pest and disease: significant increases in soluble nitrogen, amino acid and sugar concentrations in the plant cells, as the plant is unable to synthesize proteins fast enough from these building blocks. Herbicides, even in recommended concentrations, temporarily reduce protein synthesis, the most sensitive of metabolic processes. Spraying with fungicides and insecticides also contribute to reducing protein synthesis.

This is critical because reducing protein synthesis results in the soil temporarily accumulating free amino acids (soluble nitrogen). When pests are offered soluble free nutrients, the pests grow bigger and multiply faster. The herbicide, fungicide and insecticide applications are then required again, there is a brief knock-back period as a result of the application, and then the cycle begins again. As title of this article suggests, round and round we go.

Where the process of protein synthesis dominates over protein breakdown in a plant, disease resistance is strongest. Thus, the ratio of nitrogenous compounds to reducing sugars could serve as criteria in determining plant susceptibility to disease.

The biochemical and physiological state of the plant determines whether pests or disease can invade, and this state is strongly affected by the method of cultivation. Limiting the amount of soluble nutrients or, more realistically, practicing a more balanced approach that involves the use of organic products, can reduce pest and disease pressure.

In trying to maintain the health of our own bodies we know that too much of just about anything typically spells trouble, that moderation and balance are key. This is no different for plants.