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L’association de cultures avec les oliviers – arbre emblématique de la région – est une pratique ancienne en Méditerranée. Cette agroforesterie est reconnue pour fournir de multiples services écosystémiques. En Tunisie, l’un des plus importants pays producteurs d’huile d’olive, les systèmes agroforestiers à base d’oliviers sont peu documentés. Ce travail vise à caractériser les principaux systèmes oléicoles agroforestiers existants au nord et au centre du pays, et à comprendre les raisons qui sous-tendent leur adoption. Pour ce faire, une analyse cartographique a d’abord été réalisée pour appréhender la diversité des milieux oléicoles à l’échelle nationale. Vingt-et-un systèmes oléicoles différents ont été identifiés. Sur cette base, un diagnostic agronomique sur deux sites représentatifs de cette diversité a permis de caractériser la structure des systèmes agroforestiers à l’échelle parcellaire. Cinq types de systèmes agroforestiers à base d’oliviers se distinguent en fonction du choix des espèces associées : cultures maraîchères, polyculture, arbres fruitiers, pâturage pour le cheptel et grandes cultures. Une série d’enquêtes a enfin été réalisée auprès d’agriculteurs pour comprendre les choix d’agencement de ces systèmes et la perception qu’ils en ont. Leur mise en place et les pratiques culturales des agriculteurs sont souvent déterminées par des contraintes économiques ou foncières, et non d’intérêts agronomiques et environnementaux.

Organic matter water extract, or so-called 'tea', may be used to correct nutrient deficiencies in crops or enhance their defense systems. Such tea mixtures are prepared locally by Mediterranean farmers to offset a multitude of constraints, particularly a scarcity of organic manure or high synthetic input costs. However, the diverse range of tea production and usage practices and farmers' underlying rationales have yet to be thoroughly studied. Yet locally they constitute real alternatives that allow farmers to maintain their income levels while reducing reliance on chemical inputs. The main objective of this study was to gain insight into farmers' rationale and practices regarding the production of homemade dry manure tea (HMT) in North Africa, while also highlighting the benefits perceived by farmers. Nearly 50 interviews with farmers were thus conducted in three irrigated cropping areas in Morocco, Algeria and Tunisia. Our results showed that HMT is widely used in intensified family horticultural cropping systems that usually rely on drip irrigation and chemical fertilization. The analysis of farmers' practices revealed that HMT was generally made from aged manure that was pure or consisted of a mixture of sheep, cow or poultry dung. The production protocol varied in terms of drenching techniques, maceration time, container volume and type, and filtration techniques. Farmers applied the derived tea via the drip irrigation system, regularly or with a limited number of applications. The analysis of farmers' rationales and perceptions regarding HMT clearly highlighted that they felt that these practices played a positive role. HMT was considered to improve vegetative growth, yield and, to a lesser extent, soil properties. These benefits could in turn lead to decreased use of synthetic fertilizers by farmers, while boosting their income. The increased understanding of HMT and the underlying rationales showcased in this study could help scientists better analyze and assess these practices in the future. The findings could also facilitate improvement and wider dissemination of these practices to achieve more sustainable irrigation systems in the intensified irrigated cropping areas that abound in North Africa. [ABSTRACT FROM AUTHOR]

Recent trends in peach orchards have focused on intensification and high density plantings using different Prunus rootstock species with different vigor traits. This investigation aims to study the physiological behavior of different Prunus rootstocks in order to identify the most suitable rootstock under warm Mediterranean conditions. Field agronomic performance and foliar nutrient content of the flat peach cultivar 'Subirana' grafted on ten different Prunus rootstocks were studied on calcareous soil typical of the Mediterranean area. Ten rootstocks: 'ADAGAF 04-03', 'AGAF 0301-04', 'Garnem', 'Krymsk® 1', 'Krymsk® 86', 'PAC 847', 'PADAC 04-01', 'PADAC 150', 'PM 105 AD', and 'Rootpac® 70', were considered. Vegetative growth, chlorophyll SPAD index, leaf mineral status and deviation from the optimum percentage (DOP) index were determined. Leaf chlorophyll content varied depending on the rootstock. 'PADAC 04-01' and 'ADAGAF 04-03' showed higher chlorophyll index. The lowest SPAD values were observed for the most dwarfing rootstock 'Krymsk® 1', which showed visual chlorosis symptoms, and lower leaf mineral contents compared to the other rootstocks. Peach trees on Prunus rootstocks showed differences in leaf macronutrient and micronutrient content. 'Rootpac® 70', 'ADAGAF 04-03' and 'PADAC 04-01' had better adaptation under warm Tunisian conditions but high ΣDOP index. The most invigorating 'Garnem' had the highest imbalanced nutritional status, but continues to perform well under warm conditions. Interesting results were obtained with 'Rootpac® 70' showing one of the best balanced nutritional values (average ΣDOP index). However, the most dwarfing rootstock 'Krymsk® 1' presented the worst adaptation to the studied warm Mediterranean conditions. [ABSTRACT FROM AUTHOR]