Wednesday, March 13, 2013

Plant Resistance: Top to Bottom and Bottom to Top

As in humans, plants have genetic material in them to help fend off disease infections and damage from insects. This is called the plant’s natural defense system. Certain genes in the plants makeup are responsible to keep all systems going strong, even when the plant is attacked from a soil borne pathogen, an insect infestation, or the negative impact of excessive heat or flooding. But what happens when an event is so strong that it over shadows the plant’s ability to take care of itself? Fortunately, there are two systems that can be put into play to help the plant take care of itself; they are called SAR and ISR.

ISR, Induced Systemic Resistance, can start at the earliest part of the seedling development. ISR can be triggered by many bacteria and fungi as well some natural compounds but for this discussion I want to concentrate on two types of Plant Growth Promoting Rhizobacteria, PGPR, namely Pseudomonas fluorescence and Pseudomonas putida. When applied on the seed or onto the roots of transplants, these bacteria form an association with the root system triggering the systemic resistance. To compare this with a human analogy, it’s like getting a flu shot to prevent the flu.

SAR, Systemic Acquired Resistance, is a system by which the plant tries to repair damage that has already been done. In the case of insect or disease damage to the foliage, the genes responsible will cause rapid healing of the damaged tissue in order to stop the spread of the pathogen.  We have found that certain compounds, Salicylic Acid and phosphite products can ramp up the SAR in plants that are infected with pathogens. This is very important in the case of viruses because reducing the symptoms, which SAR can do if triggered early enough, on the plant tissue should reduce the negative impact of the virus and allow the plant to develop normally.

So what does this all mean? We at Ag Tech Services, LLC have the PGPR inoculants that will give you the benefits of ISR plus many, many more. We also have a program that reduces the damage caused by a particular virus using a Salicylic Acid product in combination with calcium. By reducing the symptoms on the tissue we should be able to manage the virus which is better than trying to eradicate it.

It’s all about plant health from the bottom up to the top down.