“Opuntia ficus indica cladodes as bioproducts from Sicilian organic orchards"

Italy is the most important supplier of Opuntia ficus-indica (OFI) fruits in Europe. Despite the widespread consumption of cladodes for food and feed in many countries, the industrial interest for them is just at infancy stage in Italy. In specialized OFI orchards, pruning produces annually a range of 6-10 tons/hectare of cladodes and immature fruits, which represents the main costs for farmers, not easy to be disposed. The possibility of recovering this biomass from waste and recycling into high added value bio-products, implies non only a reduction of crop management costs, but it could generate an income diversification for farmers. Recent studies on cladode high-value components, contribute to boost the European market demand for bio-products mainly addressed to food/nutraceutical/pharmaceutical applications. In this perspective, the experimental work was focused on: 1) the detection of the effects of type of soil (sandy or clayey), irrigation and seasonal variations on chemical composition (polysaccharide and polyphenols content) of cladodes in plants grown in Sicilian organic orchards (Italy; two years experimental randomized field trials); 2) the improvement of plant growth by microbial bio-stimulant inoculations in OFI plants grown in pots; 3) the determination of the physiological and biological effects of soil amendment with cladode residues on plant growth. The field trials indicated that seasonal variations, type of soils and irrigation regime influenced significantly the qualitative and quantitative composition of carbohydrates and phenolic compounds. Therefore, natural resources and cultural practices are crucial in defining the quality of cladodes when addressed to food/nutraceutical applications. Besides, the inoculation with plant growth promoting bacteria seems to accelerate the cladode sprouting. Compared with the control, the presence of cladode residues into soil increased the availability of soil water, determining an apparent reduction in soil density. Due to is ‘multi-functionality’ OFI is indicated as one of the species of the future, our results may contribute to disclose its potentialities in the contest of bioeconomy and circular economy.