The downy mildew disease, caused by the biotrophic oomycete Peronospora variabilis, is the largest environmental threat to quinoa (Chenopodium quinoa Willd.) cultivation in the Andean highlands. However, so far no molecular information on the quinoa-Peronospora interaction has been reported. Here, we have developed tools to study the downy mildew disease in quinoa at gene expression level. Living P. variabilis could be isolated and maintained in the presence of a fungicide, allowing the characterization of downy mildew disease progression in two differently susceptible quinoa cultivars under controlled conditions. Quinoa gene expression changes induced by P. variabilis were analysed by qRT-PCR for quinoa homologues of Arabidopsis thaliana pathogen-associated genes. Overall, we observed a slower disease progression and higher tolerance in the quinoa cultivar Kurmi than in the cultivar Maniquena Real. We also observed that quinoa orthologs of A. thaliana genes involved in the salicylic acid defense response pathway (AtCAT2 and AtEP3) did not have changes in its gene expression. In contrast, quinoa orthologs of A. thaliana gene markers of the induction of the jasmonic acid response pathway (AtWRKY33 and AtHSP90) were significantly induced in plants infected with P. variabilis. These genes could be used as defense response markers to select quinoa cultivars that are more tolerant to P. variabilis infection.concentrations has further raised the interest in quinoa to meet future food demands internationally [1,[3][4][5]. However, quinoa production in the major original cultivation areas is strongly limited by the downy mildew disease, which can reduce the yield by 35-90% [6-9]. The downy mildew disease is caused by the oomycete P. variabilis Gäum. [4, 10, 11] and has been spread to every continent where quinoa is cultivated [12][13][14][15][16]. The worldwide distribution of P. variabilis has likely been expanded by commercial trade of infected seeds [17, 18]. P. variabilis specifically infects Chenopodium species and is an obligate biotroph [19,20]. Little is known about P. variabilis biology, including mode of transmission, leaf penetration and signals for sporangiospore and oospore formation [21]. Most of the studies of P. variabilis have been oriented on screening quinoa cultivars for resistance in agricultural fields and observe quantitative differences in susceptibility [6-8, 16, 22, 23]. Some studies have evaluated the resistance of different quinoa cultivars to P. variabilis infection under controlled conditions [24,25] or detached leaf assays [12]. However, mechanistic understanding or molecular studies of the interaction of quinoa with P. variabilis or the downy mildew disease progression are not available. With the recent availability of the genomic sequences of quinoa [26][27][28] and the close relatives to P. variabilis, Peronospora tabacina [29] and Hyaloperonospora arabidopsidis [30,31], improved methodology and knowledge on the infection cycle of P. variabilis can open up for detailed molecular studies...

SARS-CoV-2 genomic surveillance has Illumina technology as the golden standard. However, Oxford Nanopore Technology (ONT) provides significant improvements in accessibility, turnaround time and portability. Characteristics that gives developing countries the opportunity to perform genome surveillance. The most used protocol to sequence SARS-CoV-2 with ONT is an amplicon-sequencing protocol provided by the ARTIC Network which requires DNA ligation. Ligation reagents can be difficult to obtain in countries like Bolivia. Thus, here we provide an alternative for library preparation using the rapid PCR barcoding kit (ONT). We mapped more than 3.9 million sequence reads that allowed us to sequence twelve SARS-CoV-2 genomes from three different Bolivian cities. The average sequencing depth was 324X and the average genome length was 29527 bp. Thus, we could cover in average a 98,7% of the reference genome. The twelve genomes were successfully assigned to four different nextstrain clades (20A, 20B, 20E and 20G) and we could observe two main lineages of SARS-CoV-2 circulating in Bolivia. Therefore, this alternative library preparation for SARS-CoV-2 genome sequencing is effective to identify SARS-CoV-2 variants with high accuracy and without the need of DNA ligation. Hence, providing another tool to perform SARS-CoV-2 genome surveillance in developing countries.