How Much CO2 Can a Tomato Plant Tolerate?

Tomato plants are known for their ability to efficiently convert carbon dioxide (CO2) into oxygen through photosynthesis. However, the rising levels of atmospheric carbon dioxide due to human activities such as burning fossil fuels, deforestation, and industrial processes have contributed to the increased concentration of CO2 in the air. It has raised concerns about the effects of high CO2 levels on tomato plants' growth and yield. This article discusses the maximum CO2 concentration that tomato plants can tolerate without compromising their growth and productivity.

The Optimal CO2 Concentration for Tomato Plants

Tomato plants grow best in an environment with a CO2 concentration of between 800 to 1200 parts per million (PPM). The concentration levels of CO2 in the atmosphere have now exceeded 400 PPM, which can affect the plant's photosynthesis process. When there is inadequate CO2 concentration, plants are unable to produce the essential sugars and carbohydrates necessary for their growth and development.

However, increasing the CO2 concentration above 1200 ppm does not guarantee a proportional increase in plant growth and productivity. Plants can experience diminishing returns when exposed to very high CO2 concentrations. When CO2 concentration levels exceed 1500 ppm, tomato plants' growth may be stunted.

The Effects of High CO2 Concentrations on Tomato Plants

While CO2 is essential for plant growth, exposing tomato plants to high CO2 concentrations can negatively affect their growth and development. In addition, high CO2 concentration can also cause some plant physiological changes such as:

Leaf area reduction

Reduced stomatal conductance

Delayed flowering

Reduced fruit set and size

Reduced nitrogen content in the leaves

These changes may harm tomato plants' yield and quality, thus altering their nutritional value. Furthermore, elevated CO2 concentration can increase pathogen growth, such as powdery mildew, which can harm tomato plants.

How to Control CO2 Concentrations for Tomato Plants

The most effective way to control CO2 concentration for tomato plants is in greenhouse or indoor cultivation. Growers can use CO2 supplementation, which involves adding CO2 to the air to achieve optimal concentration levels for plant growth. Supplemental CO2 can be achieved using standard combustion of propane or natural gas or other CO2 generation systems.

To get the best results, growers can control the CO2 concentration by using automated devices. These devices monitor CO2 levels and release CO2 only when needed. This ensures that plants receive only the required amount of CO2, avoiding both CO2 depletion and excess, which may affect plant growth and development.

The Bottom Line

Optimal CO2 concentration is essential for tomato plants' growth and development. While high concentrations can stimulate photosynthesis and improve productivity, they can also have negative effects on growth and yield. Growers need to maintain the right balance of CO2 concentration for optimal plant productivity. Therefore, it is necessary to control and monitor CO2 concentrations in greenhouse and indoor cultivation, requiring growers to use automated devices or other means for efficient and effective control.