Harnessing the power of photosynthesis
During our schooling days, we were all taught the basic principles of photosynthesis, that is, plants use sunlight, water and carbon dioxide to produce sugars and oxygen. In this blog, we delve a little deeper into photosynthesis and why harnessing its power is key to farm health.
Photosynthesis – the basics
Unlike animals (including humans), plants cannot roam around consuming food to provide them with energy to carry out the necessary processes to sustain life. Plants rely on energy from the sun (sunlight), carbon dioxide (CO2), water (H2O) and the microorganisms in the soil to supply them with nutrients they need to grow and thrive. This symbiotic relationship has developed over 500 million years, and up until industrial agriculture, this was working very well. Indirectly, the process of photosynthesis sustains life on Earth by providing organic matter, food and oxygen.1
Photosynthesis actually has two stages, like the word photo (light) and synthesis (make).
Stage One –
Light energy is absorbed by the chlorophyll in the plants and is converted into chemical energy. The water molecule is split into Hydrogen and Oxygen and ATP (Adenosine Trisphosphate) is created.
Some oxygen is used by the cells for the plant for respiration, the rest diffuses out of the stomata of the leaves.
Stage Two –
The ATP from stage one in the presence of specific enzymes breaks down and releases energy to combine the hydrogen and carbon dioxide to form sugar2.
The complete photosynthesis process looks like this –
CO2 + H2O + light energy = C6H12O6 + O2
Carbon Dioxide + Water + sunlight = glucose (sugar) + Oxygen
What happens in respiration?
While photosynthesis can only happen while the plant has access to light energy, respiration occurs both during the day and at night. Unlike photosynthesis, respiration takes place in all cells of the plant, including the roots.
During respiration, glucose combines with oxygen to form energy (ATP*), carbon dioxide and water. During daylight, when the stomata are open, water vapour and carbon dioxide are released into the atmosphere. *(ATP powers the activities within the plant cell)
Gas exchange cannot occur at night, as the stomata are closed. However, the plant roots can absorb the oxygen needed for respiration during the night; this is why soil aeration is so important for plants to complete this vital process.
The energy created by respiration is critical for protein synthesis and cell division.
If soils have poor drainage or waterlogging the roots are deprived of oxygen, which can result in disease and reduced yields.
Complete photosynthesis
Glucose is a simple sugar. For plants to grow, reproduce and flower, they need to convert glucose into more complex sugars, carbohydrates (like starch and cellulose) and fats.
For photosynthesis to be complete, plants need to convert simple sugars, by linking them together to form more complex carbohydrate molecules that are essential for improving plant structure and disease resistance.
According to John Kempf, most plants are only photosynthesising to 25% of their genetic capacity3. By providing balanced nutrients to plants, we can easily boost photosynthesis by 3 or 4 times, which will not only increase the quantity, but also the quality of the sugars.
Roles of sugars, carbohydrates and fats
The molecules and compounds found in plants play vital and specific roles.
Glucose: provides energy and is the building block for more complex compounds
Starch: energy store in plants
Cellulose: structural component giving cell walls rigidity and support
Sucrose: acts as a signalling or messenger molecule in the plant
Fructose: key energy source and is involved in attracting animals for pollination and seed dispersal
Lipids (fats): structural components of cell membranes, energy storage, signalling molecules and response to environmental stress (ie waxy layer on leaf)
How do I increase photosynthesis?
Advancing Ecological Agriculture provides a Plant Health Pyramid, which delves into the 4 Levels of immunity and how to achieve complete resistance to diseases and insects4, and is discussed on the Biological Farming RoundTable podcast.
When applying your foliar nutrient program, adding NutriSoil Biological Solution will help increase photosynthesis and nutrient uptake efficiency. The diversity of microbes and other compounds, such as secondary metabolites, humic and fulvic substances (to name a few), found in NutriSoil, is key to maximising this process.
Along with balanced nutrition, biology is key to optimising photosynthesis, and NutriSoil Biological Solution makes the ideal biological companion to your nutritional application.
References
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1. https://www.sciencedirect.com/topics/neuroscience/photosynthesis
2. https://www.bbc.co.uk/bitesize/guides/zcktw6f/revision/3
3. https://advancingecoag.com/article/plant-health-pyramid-1-photosynthesis/
