Updated: Jan 7
A new experiment conducted by Green Praxis to adapt fruit production to a drier climate. The underlying idea is that microscopic organisms (mycorrhizae) in the soil play a key role in supporting tree growth. It was the expertise of Professor Robin Duponnois of IRD that validated this experiment. These micro-organisms are associated with specific "companion" or "nurse" plants. We will therefore associate trees with different types of companion plants to show how much better they can do when these associations are implemented.
Photo: 4 types of 'nurse" plants. Genista, cistus, dorycnium and Lavandula.
Objective: : The experiment will be carried out on 4 plots. Each plot will be planted with 15 pear trees of local varieties and 15 apricot trees of local varieties (which will ensure the adaptation of the plant genome to the conditions of the test site) - the total will be about 120 trees. These species will be planted at a distance that will allow them to grow well. In each plot, companion plants will also be planted to evaluate the effect of species associations on fruit tree productivity and the development of mycorrhizae in the soil.
Context: in the Mediterranean area, plants are likely to suffer greatly from the effects of climate change, especially prolonged drought. It is known that mycorrhizal associations help plants to adapt to drought and that the latter are notably favoured by the establishment of plants of the Fabaceae family.
Protocol: Four different plots will be installed and monitored; as much as possible, they should be in similar conditions (same altitude, exposure, slope, edaphic humidity, and surrounding vegetation, etc.).
Plot 1: Cistus albidus as companion plant; as dense as possible.
Plot 2: Lavandula angustifolia as companion plant; as dense as possible.
Plot 3: Dorycnium pentaphyllum in companion plant, as dense as possible
Plot 4: nothing (control plot).
Monitoring and evaluation: If possible, an initial state of the presence/quantity of mycorrhizae in the soils of the four plots will be carried out by the IRD. Then, a periodic (annual) evaluation of mycorrhizal development in the plots can be carried out, in the same way, to assess whether these combinations with native species have favoured mycorrhizal development. We can replace some companion plants with larger species: Spartium junceum or a Genista (but thorny).
The productivity of the plots can also be compared by assessing the health status of the individuals and by taking some measurements indicative of their growth rate (height, trunk diameter at one meter high). It can also be assessed by comparing the quality and quantity of fruit production between plots.
UPDATE 5th January 2021 - Trees in the ground! On 5th January 2021, a team of 6 determined individuals from the Green Praxis company - investors, advisors and founders executed the planting of over 140 trees. Temperatures did not rise above freezing. The grounds were prepared a few days before and we planted 4 rows of apricot and pear trees associated as planned with Lavender, cistus and broom trees. Some of the pictures we took on the day: