RESIOLIVA Operational Group: Improving the resilience and sustainability of rainfed olive groves through consortia of beneficial fungi, biochar, and phytosanitary certification

The project will be developed in two phases.

1. The Documentary Phase will comprise the first stage of the project. During this phase, information will be gathered on the work carried out by other research teams and companies, primarily focused on obtaining information on: the development of certified mycorrhizal olive plants; preliminary studies on biochar production from olive biomass, olive pomace, and olive pits and their application in soils in conjunction with Trichoderma sp.; the prediction of study parameters to evaluate the plant's effects in the field; and the development of methodologies to assess its effects on the carbon cycle and soil quality.
2. The Experimental Phase will be coordinated by Plantas Continental, SA, with the participation of all partners in this Operational Group. It will include the following tasks:
   1. Activity 1.- Certified Plant Production. Plantas Continental, SA will produce Certified Plants (mycorrhizal and non-mycorrhizal) in sufficient quantities to ensure that all trials have a similar plant count. In a super-intensive olive grove, the approximate number of plants is around 1,700 plants/ha. The plant will be produced at the company's own facilities in the hamlet of Rivero de Posadas, in the municipality of Posadas (Córdoba). The mycorrhization of the plants will be monitored by Cambrico Biotech.
   2. Activity 2.- Production and supply of agronomically suitable biochar and its characterization. Carboliva, SLU will produce the biochar required for the entire project from plant residues from olive groves, including dried olive pomace and olive pits. Researchers from the IRNAS-CSIC team will conduct a complete characterization of the biochars supplied by Carboliva, SLU.
   3. Activity 3.- Planting under dryland conditions. The planting will take place on a dryland olive grove in the municipality of Fuentes de Andalucía (Seville). Biochar will be incorporated into the soil to locate it in the area where the olive tree roots will establish themselves. A dosage of 5 t/ha has been chosen.
   4. Activity 4.- Effect of atmospheric CO2 emissions on soil C sequestration and quality The flux of CO2 from the soil to the atmosphere is an important component of the total carbon balance and an essential variable in any study of global climate change. CO2 emissions will be measured periodically in the soils of the study plots, using the LI-COR “Automated Soil CO2 Flux System” equipment available at IRNAS-CSIC. For each plot, 6 PVC rings (8 cm radius x 5 cm height) will be installed and maintained throughout the project for bimonthly measurements of CO2 emissions. This task will be led by the IRNAS-CSIC Research Group.
   5. Activity 2.5.- Evaluation of plant development in the field We will work with Certified Olive Plants; mycorrhizal and non-mycorrhizal. And of each of these modalities, three treatments are applied: Biochar + Trichoderma, Biochar and Control. Of each of the treatments, 1 ha will be planted and the following aspects will be analyzed on each of them to evaluate their adaptability and resilience: Losses, Growth, Health and Harvest