“Viruses seem to be parasites by nature. So one would conclude, therefore, that their ability to reproduce must be affected by changes produced in the metabolism of the host plant caused by variations in nutrition,” Bawden and Kassanis (1950). This makes a lot of sense. Viruses look for vulnerabilities, whether it’s a rundown human being or a chemically dependent plant.
Plants are constantly working to establish a cooperative or synergetic relationship with the microbial community in the soil. The introduction of synthetic fertilizers, especially high doses of nitrogen, disrupt this relationship. As the plant works to establish the relationship, the injection of nitrogen interrupts the process — the plant doesn’t push as hard to generate root growth. I think that we’ve all seen pictures showing the disparity of root growth resulting from the use of inorganic nitrogen in comparison to the application of organic fertilizers and biostimulants.
The plant, literally, becomes a couch potato as it simply doesn’t have to work as hard to generate growth. This is the opening for plant diseases like viruses. If a plant has extended root growth, it has access to more water and nutrients and as a result, it’s healthier or more resilient. The plant has had to generate a hardier structure to survive.
My intention isn’t to discourage the application of synthetic nitrogen fertilizers but to limit their application by supplementing them with organic nitrogen-based products like fish, blood meal, soy, etc., as these additions create more biology in the soil giving rise to plant health. Basically, they make the couch potato get more exercise.
In a UC Davis study, as reported in California Agriculture in 1995, excess nitrogen raised nectarine susceptibility to disease and insects. Applying higher rates of N fertilization produced no beneficial effects. The N treatments had no effect on most of the postharvest parameters measured. Among the parameters that were affected by N treatments were potential water loss and cuticle thickness, which affect postharvest storage potential and brown rot susceptibility. So nitrogen fertilization was positively correlated with increased levels of brown rot blossom infection. In the higher N treatments, there was also an increase in the symptomless infections of green fruit (latent infections) and the susceptibility of mature fruit to brown rot. Increased N resulted in a greater number of fruit dropped and decayed by brown rot and in more mummified fruit hanging on the trees. Increased N fertilization was also correlated with greater OFM (Oriental Fruit Moth) and PTB (Peach Twigg Borer) fruit infestations — we’ve learned that insects attack crops that cannot process nitrates (metabolism slowdown) and they are attracted to excess nitrates.
These conclusions explain the difficulties in eliminating viral diseases if you don’t take into account the complex effects of chemical fertilizers on the plant’s metabolism. Introducing biological fertilizers can greatly benefit conventional growers and typically it produces very measurable results.
Andaman Ag offers a host of organic fertilizers and biostimulants. Please visit our website or feel free to contact me directly.
As always, I’m happy to talk to you about our products and sustainable and organic growing practices.