Agrobiotechnology in turfgrass - ACC deaminase

The impact of Agrobiotechnology on turfgrass continues to surprise us every day. Today, the ACC-Desaminase is under the spotlight.

1-aminocyclopopane-1-carboxylic acid, also known as ACC-desaminase, helps to combat the effects of stress.

1-aminocyclopopane-1-carboxyl acid, also known as ACC-desaminase, is a powerful ally produced by micro-organisms in the rhizosphere. This substance prevents oxidation of plant tissues in times of stress due to ethylene production.

Bacteria in the rhizosphere produce many substances, including ACC-desaminase. What is it for? Why is it so important?

In the journal Corpoica - ciencia y Tecnología Agropecuaria Mr. Mauricio Camelo R., S. P. in 2011 defined these mechanisms in detail in the article Mecanismos de acción de las rizobacterias promotoras del crecimiento vegetal (Mechanisms of action of plant growth promoting rhizobacteria).

Before answering the two questions above, it is important to explain what ethylene is and how it affects plants.

Ethylene is the phytohormone that is responsible for the stress processes in plants, which is the reason for senescence and fruit splitting. In short, it oxidises tissues and its ultimate consequence is the death of the individual. The ethylene produced by one individual affects the others, as is the case with fruit in the household.

Experience tells us that mixing ripe fruit with green fruit makes the latter ripen earlier. The same is true for all crops.

ACC-desaminase prevents ethylene from having this undesirable effect on plants. It degrades ethylene, mitigating the effects of stress, and during the process ammonium is released which can be very easily assimilated by the crop.

Ammonium is a fast source of nitrogen for crops.

The beneficial effects of ACC-desaminase produced by PGPR (soil micro-organisms) have been shown to be:

• Reducing the overall effects of stress
• Water stress due to salinity
• Anaerobic stress
• Passive pathogen resistance
• Heavy metal and hydrocarbon stress
• nutrient stress (inability to produce new chlorophyll)

In short, the bacteria that synthesise ACC diseminase are an essential support to mitigate the inevitable effects of stress, as they reduce plant ageing. In other words, under stress the roots are still able to receive water and nutrients. Leaves maintain their biomass and chlorophyll.

This is just one mechanism among many. Promoting one in particular may not have a visible effect, but the rhizosphere and all the life it inhabits must be taken into account. New agricultural practices are aware of this situation. Aggressiveness and sterilisation of soils will soon be obsolete.