Mineral nutrients are essential for the growth and development of plants and microorganisms, and they are important factors in plant-disease interactions. Nutritional disorders are basically physiological disorders in the plants that affect productivity as well as the quality of the fruit. Interestingly enough, in fruit crops a deficiency of micronutrients causes many more disorders than macronutrient deficiency. To get high quality fruit and yields, micronutrient deficiencies have to be detected before visual symptoms are expressed. Conducting a Leaf Extract Analysis to look at the mineral content of plant fluids is good place to start.
When a pathogen infects a plant, it alters the plant’s physiology, particularly with regard to mineral nutrient uptake, assimilation, translocation, and utilization. Some pathogens may themselves utilize nutrients, reducing their availability to the plant and thereby increasing the plant’s susceptibility to infection.
For example, copper (Cu) is a plant nutrient that is widely used as a fungicide. From a nutritional perspective, Cu deficiency leads to impaired defense compound production, accumulation of soluble carbohydrates, and reduced lignification (wood development), all of which contribute to lower disease resistance.
In order to complement disease and pest control methods, it is helpful to know how mineral nutrients affect disease resistance in plants. There are two primary resistance mechanisms that mineral nutrition can affect:
- The formation of mechanical barriers, primarily through the development of thicker cell walls.
- The synthesis of natural defense compounds such as phytoalexins, antioxidants, and flavonoids that provide protection against pathogens.
As a rule, plants with an optimal nutritional status have the highest resistance (tolerance) to pests and diseases. Susceptibility increases as nutrient concentrations deviate from this optimum. The roles of mineral nutrients are well established in some areas of host-disease interaction. The goal is to recognize these interactions and see the possibilities and limitations of disease and pest control by mineral nutrition and fertilizer applications.
We know that magnesium (Mg), iron (Fe), manganese (Mn), nitrogen (N) and phosphorus (P) are important elements for maximizing plant photosynthesis, or the plant engine, and that the addition of molybdenum (Mo), boron (B) and sulfur (S) can help plants synthesize proteins and become more disease and insect resistant.
Andaman Ag offers a host of tools to help growers mitigate pest and disease pressure. We believe that a solid nutrient plan involving both soil and foliar spray applications is essential. We have one of the few flavonoid products in the market, called CropBioLife, that boosts the natural defenses of the plants and contributes greatly to mineral assimilation.