"An analysis allows us to know in plants what blood reveals in human beings."

Being able to measure their mineral content allows us to know more accurately the internal metabolism of plants, through:

1. Quantify the minerals that are not incorporated into the tissues of the plants and therefore flowing in the sap stream.
2. To know the minerals that are being absorbed through the xylem and phloem.
3. Determine the mobility of nutrients, both macro and micronutrients.
4. Determine the state of the plants using metabolic indicators (% of sugar and °Brix).
5. Knowing chemical parameters such as pH and EC.
6. Evaluate nitrogen metabolism by quantifying the levels of ammonium, nitrates, amino acids, and proteins.

Difference between sap and tissue analysis:

The most important difference is that the first one allows us to measure the flow of minerals available in metabolism and not all of them (including those that are fixed to cell walls and structures specific to the plant morphology of each crop).

Sample collection:

Sampling is key; just as in humans, it must be done on an empty stomach, which for plants corresponds to the period before dawn, when they have not yet begun active photosynthesis. In addition, the type of foliage to be sampled must be considered to achieve the greatest possible representativeness of the trees, reflecting the reality of the orchard under control and representing the individual tree being evaluated.

Interpretation:

Understanding the dynamics of minerals within plants and their behaviors, according to molecular weights, positive (cations) and negative (anions) charges, as well as the balances between them, reveals whether plants are effectively balanced internally or have the necessary elements and in sufficient quantity to carry out the different physiological processes.

Among the most important parameters to evaluate, which generally reflect whether or not the plants are functioning optimally, are:

• % of sugar and °Brix, reflecting photosynthetic activity
• The mobility of minerals
• Trace element levels
• Efficiency in nitrogen conversion.

Internal movement of plants:

The two most important structures of plant circulation are Xylem and Phloem, both main structures that conduct sap.

Xylem, responsible for the upward transport of water and mineral ions.

Phloem, responsible for the upward and downward transport of water, minerals, sugar, proteins, as well as exudates towards the root, and which plants use for the exchange of metabolites with the soil's microbial flora, when it is present in sufficient quantities.

Moving and immobile elements:

Based on their mobility, deficiencies or excesses of any of these nutrients can be detected early, whether in new foliage or mature plants, by clearly understanding their behavior within the plant's internal flow. In this way, nutrition programs can be adjusted periodically to increase not only yield potential but also to induce specific metabolic functions with production goals.

Relationship between minerals and metabolic functions:

The wide variety of minerals in the sap performs specific metabolic functions depending on how they are combined, whether by enhancing nitrogen metabolism, reproductive functions, or photosynthesis.

Conclusions:

While everything mentioned above may seem complex, it is actually just information suitable for not only fertilizing, but also nourishing plants with what they need to reach their maximum productive potential, leaving behind forensic tissue analyses, which are untimely and generally relatively rigid for a particular season, given that there are significant variations from year to year in climate, fruit load, and agronomic management.

On the other hand, it allows us to detect what is not being done correctly, such as whether the irrigation is efficient or not by evaluating the EC or the quality of the pruning by reflecting high or low sugar % and °Brix contents.

In summary, just as we humans periodically have blood tests to investigate what might be malfunctioning in our bodies, using this type of analysis in plants allows us to better adjust irrigation and nutrition, achieving the greatest possible efficiency in the entire photosynthetic process, which is responsible for the final productivity of any plant crop and, therefore, the economic business involved.

Renzo Canepa Gutierrez Chile renzo@agrocanepa.cl - + 56 9 79053241 Agro Canepa SpA