SUMMARY: The grapevine industry is of high economic importance in several countries worldwide. Its growing market demand led to an acceleration of the entire production processes, implying increasing use of water resources at the expense of environmental water balance and the hydrological cycle. Furthermore, in recent decades climate change and the consequent expansion of drought have further compromised water availability, making current agricultural systems even more fragile from ecological and economical perspectives. Consequently, farmers' income and welfare are increasingly unpredictable and unstable. Therefore, it is urgent to improve the resilience of vineyards, and of agro‐ecosystems in general, by developing sustainable and environmentally friendly farming practices by more rational biological and natural resources use. The PRIMA project PROSIT addresses these challenges by characterizing and harnessing grapevine‐associated microbiota to propose innovative and sustainable agronomic practices. PROSIT aims to determine the efficacy of natural microbiomes transferred from grapevines adapted to arid climate to commonly cultivated grapevine cultivars. In doing so it will test those natural microbiome effects on drought tolerance. This multidisciplinary project will utilize in vitro culture techniques, bioimaging, microbiological tests, metabolomics, metabarcoding and epigenetic analyses. These will be combined to shed light on molecular mechanisms triggered in plants by microbial associations upon water stress. To this end it is hoped that the project will serve as a blueprint not only for studies uncovering the microbiome role in drought stress in a wide range of species, but also for analyzing its effect on a wide range of stresses commonly encountered in modern agricultural systems.

Cereals are prone to viral infections and the economic impact of these has increased in recent years. Among these diseases barley yellow dwarf (BYD) is one of the most destructive diseases of cereals today. For three consecutive years (2014–2015–2016) surveys were carried out in order to search for BYDV species (BYDV-PAV and -MAV) as well as other cereal viruses, wheat spindle streak mosaic virus (WSSMV), southern bean mosaic virus (SBMV) and barley stripe mosaic virus (BSMV) in seven regions of Algeria (Algiers, Boumerdes, Tipaza Médéa, Adrar, Khenchla and Batna). Targeted samples were taken randomly from plants of different cereal species (wheat, barley, oats). The sample were analyzed by DAS-ELISA and RT-PCR. The results of ELISA and PCR tests showed the presence of BYDV-PAV in barley, durum wheat, soft wheat and oats. Thus, this viral species were found in all the cereal regions surveyed (North, South, East and West). Seven samples (durum wheat, barley and oats) were sequenced and phylogenetic analyses performed revealed that the Algerian sequences clustered in group I and group II.

Vineyards in western and center regions of Algeria were surveyed for the Grapevine leafroll-associated virus 2 (GLRaV-2). Analyses by DAS-ELISA and Reverse Transcription Polymerase Chain Reaction (RT-PCR) reveal 15, 8% prevalence. The genetic diversity of the GLRaV-2 population was studied by phylogenetic analyses of the HSP70h gene region of seven samples sequenced in this study and other sequences downloaded from GenBank. Results reveal segregation of the GLRav-2 population into six distinct groups. An estimation of the ratio of non-synonymous substitutions per non-synonymous site to synonymous substitutions per synonymous site indicated that HSP70h gene evolve under positive selection. Similarity plot constructed with representative sequence from each group confirmed previous results. All Algerian isolates belong to group PN. As far as we know, this is the first characterization of GLRaV-2 isolates from Algeria.

Grapevine rupestris stem pitting-associated virus (GRSPaV; Foveavirus rupestris, Betaflexiviridae) is the most widespread grapevine virus in most viticulture regions, and this virus has high genetic variability. Genetic diversity of GRSPaV in Algeria was examined, based on the complete capsid protein (CP) gene. Similarity proportions between the CP sequences varied from 76% to 99%. The complete coding sequence of Algerian GRSPaV isolate ALG99 (8,646 nt) was determined using high-throughput sequencing and bioinformatic analyses. Algerian GRSPaV isolates clustered into four groups, with most sequences in groups III and IV. This research is the first to determine the genetic variability of GRSPaV in Algeria.