John Kempf’s plant health pyramid
Level 1 – Plants are able to create carbohydrates and transfer them to the root zone as root exudates. This provides resistance to soil-borne pathogens such as fungal diseases like fusarium or verticillium.
Level 2 – Plants are able to form complete proteins. This provides resistance to sucking and chewing insects. Foliar sprays of Mg, S, Mo, B and molasses are helpful for control.
(Levels 1 and 2 are a function of balanced chemistry in the plant.
Level 3 – Plants are able to form high levels of lipids (fats). Their leaves are shiny and they have a glow. At this point they are resistant to airborne pathogens such as powdery mildew.
Level 4 – Plants are producing plant secondary metabolites (PSMs). At this point plants are resistant to beetle attacks such as from Japanese beetles.