Trends in biofertilisation and agroecological practices for the sustainable enhancement of CAM plants growth in arid environment: the case of Opuntia ficus-indica

Abstract

Climate change is intensifying environmental constraints in arid and semi-arid regions, where agricultural systems face recurrent drought, soil degradation, salinity, nutrient depletion, and increasing biotic pressures. While perennial crops are increasingly recognized for their role in stabilizing agroecosystems, the mechanistic integration of plant functional traits, microbial symbioses, and agroecological practices remains insufficiently addressed, particularly in Crassulacean Acid Metabolism (CAM) species. Opuntia ficus-indica, a widely cultivated CAM perennial, represents a relevant model for understanding plant resilience under water-limited conditions due to its high water-use efficiency and stress-adaptive traits. This review addresses this gap by synthesizing current knowledge through a structured framework encompassing: (i) functional traits of perennial and CAM plants, (ii) responses of O. ficus-indica to major abiotic and biotic stresses, (iii) agroecological practices for stress mitigation, and (iv) the role of plant growth-promoting rhizobacteria (PGPR) and arbuscular mycorrhizal fungi (AMF) in enhancing plant resilience. Mechanistically, agroecological practices such as intercropping, organic amendments, soil conservation, and optimized water management improve soil quality and resource availability, thereby supporting plant adaptive responses. In parallel, PGPR and AMF enhance stress tolerance through complementary processes, including improved nutrient acquisition, modulation of phytohormonal balance, osmotic adjustment, ion homeostasis, and activation of antioxidant defense systems. By integrating plant functional ecology, microbial interactions, and agroecological strategies, this review proposes a conceptual framework that positions O. ficus-indica as a model CAM system for improving stress resilience. Such integrative approaches are particularly relevant for optimizing the performance and sustainability of CAM crops under multiple environmental constraints in arid and semi-arid regions.