The effect of arbuscular mycorrhizal fungi (AMF) on industrial tomato (Lycopersicon esculentum Mill. cv. Isma F1) cultivated in North-Eastern Algeria was evaluated under greenhouse and field conditions in a vertisol soil intended for the cultivation of industrial tomato. In the greenhouse, a commercial AMF inoculum and native fungal isolates consisting of Funneliformis mosseae and Septoglomus constrictum, were added in sterilized or non-sterilized soil and tested for their effects on the growth of tomato. Inoculation with exotic AMF in the commercial inoculum or with native isolates had similar effects in increasing mycorrhizal root colonization rates and tomato growth. In the field, the commercial AMF inoculant was combined with three rates of chemical fertilizer used for the cultivation of industrial tomato (mono-ammonium phosphate, ammonium sulphate and NPK, applied at 0, 50 and 100% of the recommended dose). Introduced AMF significantly improved mycorrhizal root colonization levels, growth and yield as compared to the indigenous AMF alone. In addition, in the presence of the mycorrhizal inoculant, an application of 50% of recommended fertilizer dose provided the same yield as the full fertilizer dose without inoculation. Results clearly show that in this soil, plants needed both fertilization and AMF inoculation to achieve optimal growth and yield, and that the application of AMF can compensate for the reduction in chemical fertilizers, offering a more sustainable farming system that is respectful of the environment.

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Scarcity and endemism are considered the most important concepts of a region’s biodiversity and conservation. Nevertheless, our understanding of the models of scarcity and endemism is limited to high biodiversity regions as, for example, the wilaya of Souk Ahras, northeastern Algeria. In this study, we have compiled a list of all heritage species, their taxonomic composition, and geographic distribution. A total of 119 species was documented, and their distribution was as analyzed in the biological environments of two distinct phytogeographic sectors — C1 and H2. The rate of scarcity and endemism increased alongside the organic matter richness and, as a result, the forest and pre-forest area supported an over-representation of these species. The preservation of this biodiversity, exceptional and threatened, urgently requires appropriate scientific studies and environmental protection as short term measures.

Two native Algerian mycorrhizal fungi (Glomus mosseae and Glomus intraradices) were tested for their effect on the growth of micropropagated olive tree (Olea europaea L.). The effect of inoculation of plantlets with G. mosseae was also compared with chemical fertilization using osmocote. Specific molecular techniques were then used to detect the presence of the two fungi. Highly significant increases in growth were evident for inoculated plants compared with uninoculated ones. For a slightly lower shoot growth, G. mosseae doubled the root growth of the inoculated plantlets, compared to that of the fertilized plants. This change in the root: shoot ratio permitted greater utilization of soil resources and strengthened the plant's capacity to resist transplantation shock and water stress. The abundance of the two fungi in the roots of wild olives just as in the inoculated olives is indicative of the predominance of G. intraradices when the natural microflora is present.

The identification of priority conservation areas (PCA) plays an important role in biodiversity conservation, but uncertainties create challenges for conservation planning. The objective was to test a method based on 'taxonomic distinctness' (TD) and to identify PCA to quantify the heritage value of a territory and establish the most appropriate conservation measures. The researchers performed a systematic and phytogeographical analysis of ten islands in northeastern Algeria, a biological hotspot with heterogeneous ecosystem types and subject to socio-economic pressures. The biological diversity represented by 223 species in these environments reflects a high rate of endemicity (13%).