During the summer and autumn months we often talk about the importance of accumulating reserves for the plant, the importance of the root as a storage facility and the accumulation of reserves in shoots. During this period it is time to analyse the work carried out and quantitatively identify the reserves that we will have in the plant for the reproductive processes and initial sprouting.
The quantification of reserves must be carried out in a laboratory, sending samples, as is done with soil and leaf samples; the type of root must be between 5 and 8 mm thick and, ideally, taken from a representative number of trees in the irrigation sector.
The radical importance of quantifying reserve levels is due to the fact that we are also quantifying the efficiency of our nutritional and biostimulation strategy for summer and autumn, and, in this way, we can make corrections over time. “Without data, no type of optimization can begin.”
Within the analyses the following must be measured: Arginine, Starch, Phosphorus, Potassium, Nitrogen, Protein and Calcium.
The ranges of the data provided will depend on the species to be worked on; it has been possible to identify that not all species store their reserves in shoots as in roots, in the same relationship between elements and compounds. Cherry trees, for example, store a large amount of starch in roots just like an almond tree, but much lower levels of Arginine, compared to an almond tree that has a very high capacity to store Arginine; and if compared to a walnut tree, it has the capacity to store more Arginine than a cherry tree and a lower amount of starch (Table No. 1).
Table No. 1.- Analysis of root reserves of different species.
Laboratory: Agrolab.
These differences between species require that parameters be established for cherry trees, depending on the rootstock, variety and age of the orchards.
Laboratory analysis regarding the reality of orchards
Laboratory analyses provide us with concentrations, either in percentages or mg/gr; but there is a need to compare the data provided by the laboratory with the amount of roots in the orchards. This is extremely important, since if we consider that the root (5-8 mm) is a cellar where reserves are kept, having a large cellar is not the same as having a small cellar; if you have a large root as shown in the image on the right (Photo No. 1), the cubic quantity of reserves will be large, even if the laboratory analyses show average values. On the other hand, if we have a shortage of roots, however high the laboratory data may be, the total quantity per tree will be an insufficient figure.
Photo No. 1: Root differences in Lapins cherry orchards on colt.
In addition to this, it is necessary to take into account the times in which root samples should be taken, depending on the soil and species; internal reserve movements can occur much earlier than one might think. For example, in loamy soils, for a Chandler walnut tree, internal reserve movements towards the upper section of the tree begin in the second half of July, many months before the tree begins its reproductive process. This season, work has already begun on these parameters in cherry trees, so that in the next two seasons parameters can be defined by commercial variety, rootstock, internal movements according to previous data and soil types.
