Agrobiodiversity and Sustainability of Oasis Agrosystems in Palm Groves of Sahara and Sahel in Chad

Abstract

The cultivation of date palm, a pillar of oasis agrosystem constitutes a real source of development in arid and semi-arid zones because of its fruit’s rich in sugars and various products, essential to daily life of the populations. In Chad, date production has experienced a decline since the sixties, in relation to diseases, pests and poorly performing cultivation techniques, environmental factors are major causes of the degradation of phoeniculture as well as insecurity and the phenomenon of rural exodus. In order to assess the potential of oasis agroecosystems based on the date palm in Chad, an ethnobotanical survey was carried out among date farmers of Sahara and Sahel. The cultivars of date palm is mainly cultivated in Sahara in the North of the country where it allows a rich and diversified subsistence agriculture (market gardening, fruit trees, cereals and fodder), which excludes the use of chemical inputs in production. Our study made it possible to highlight an important genetic diversity with more than 200 cultivars, resulting from empirical selection and multiplied by offshoot. In Sahara, date palms cultivars have only one fruit production season per year with satisfactory productivity, an acceptable price and farmers have a good knowledge of cultivation practises. In central part of the country corresponding to the Sahelian zone, oasis agrosystems are also found in basins. The climatic conditions favour two production seasons and the income from the sale of dates from the first fruit production season (April and May) is greater than those from the second production season (June to September). The strengthening of the local knowledge and the extension of palm groves made it possible to increase production and income and would contribute to food security and the maintenance of populations in Chad and more generally in Sahel’s countries.

Influence of geographical isolation and anthropic activities on genetic differentiation of date palm populations in Niger

“…Conversely, those of the Sahel are recent (100 years) and few cultural practices are applied (Ibrahim et al, 2020). The same information was reported by the study carried out in Chad by Oumar et al, (2022). The implementation of certain cultural practices such as modes of multiplication and modes of reproduction, leads to the appearance of new phenotypes and therefore a genotypic variation which can be interesting but also has several disadvantages (Gros-Balthazard, 2012).…”

Chromosome-scale assembly uncovers genomic compartmentation of Fusarium oxysporum f. sp. albedinis, the causal agent of Bayoud disease in date palm

“…In the context of oasis agricultural systems, it is noteworthy that all these plant hosts, including watermelon, tomato, cruciferous plants, flax, tulips, and melon, can be found cocultivated in the same geographical areas within oases ( El-Saied et al, 2015 ; Mahmoud et al, 2022 ; Houssni et al, 2023 ). This adds an interesting dimension to our findings regarding the shared ancestry and presence of specific SIX genes in FOA isolate.…”

Oasis agriculture revitalization and carbon sequestration for climate-resilient communities

“…Date palm oases are of immense cultural, economic, and ecological significance. They serve as a crucial source of income through date production, contribute to biodiversity by providing habitats for various species, and aid in mitigating desertification by stabilizing soils with their extensive root systems (Mahmoud et al, 2022;Zemni et al, 2022;Gros-Balthazard et al, 2023).…”

“…Additionally, crops cultivated alongside date palms include barley, wheat, figs, citrus fruits, and pomegranates (Mahmoud et al, 2022;Zemni et al, 2022;Gros-Balthazard et al, 2023).…”