How binomial (traditional rainfed olive grove-Crocus sativus) crops impact the soil bacterial community and enhance microbial capacities

• Published in: Journal of environmental management 2023-11, Vol.345, p.118572-118572, Article 118572
• Main Authors: Aguilera-Huertas, Jesús, Cuartero, Jessica, Ros, Margarita, Pascual, Jose Antonio, Parras-Alcántara, Luis, González-Rosado, Manuel, Özbolat, Onurcan, Zornoza, Raúl, Egea-Cortines, Marcos, Hurtado-Navarro, María, Lozano-García, Beatriz
• Format: Article
• Language: English
• Subjects: antifungal properties; Arthrobacter; Avena sativa; bacterial communities; Bacterial community; Bacteroidetes; Conventional tillage; cover crops; Crocus sativus; environmental management; Enzymatic activities; Intercropping; Lavandula; nitrogen fixation; olives; Proteobacteria; Saffron; soil; soil bacteria; Spontaneous vegetation; tillage; total nitrogen; total organic carbon; Vicia sativa
• ISSN: 0301-4797; 1095-8630
• DOI: 10.1016/j.jenvman.2023.118572

Intercropping can favour the yield of the main crop. However, because of the potential competition among woody crops, this system is rarely used by farmers. To increase knowledge about the intercropping system, we have explored three different combinations of alley cropping in rainfed olive groves compared to conventional management (CP): (i) Crocus sativus (D-S); (ii) Vicia sativa/Avena sativa in annual rotation (D-O); and (iii) Lavandula x intermedia (D-L). Different soil chemical properties were analyzed to evaluate the effects of alley cropping, while 16S rRNA amplification and enzymatic activities were determined to study the changes that occurred in soil microbial communities and activity. In addition, the influence of intercropping on the potential functionality of the soil microbial community was measured. Data revealed that the intercropping systems highly affected the microbial community and soil properties. The D-S cropping system increased soil total organic carbon and total nitrogen that were correlated with the bacterial community, indicating that both parameters were the main drivers shaping the structure of the bacterial community. The D-S soil cropping system had significantly higher relative abundances of the phyla Bacteroidetes, Proteobacteria, and Patescibacteria compared to the other systems and the genera Adhaeribacter, Arthrobacter, Rubellimicrobium, and Ramlibacter, related to C and N functions. D-S soil was also related to the highest relative abundances of Pseudoarthrobacter and Haliangium, associated with the plant growth–promoting effect, antifungal activity, and a potential P solubilizer. A potentially increase of C fixation and N fixation in soils was also observed in the D-S cropping system. These positive changes were related to the cessation of tillage and the development of a spontaneous cover crop, which increased soil protection. Thus, management practices that contribute to increasing soil cover should be encouraged to improve soil functionality. [Display omitted] •Intercropping affects soil microbial communities improving soil health.•Soil cover (saffron + spontaneous cover) affected microbial community.•Soil C and N increased with saffron + spontaneous cover.•Management increasing soil cover should be encouraged to enhance soil functionality.