Transcriptomic Analysis of Quinoa Reveals a Group of Germin-Like Proteins Induced by Trichoderma

In silico analysis of betaine aldehyde dehydrogenase (BADH) gene in different cultivars of Chenopodium quinoa

Chenopodium quinoa is an emerging halophyte plant that has gained significant attention from researchers in recent years due to its high nutritional value and resilience to environmental stress. This plant serves as an excellent substitute for rice and wheat. However, there has been limited research on it, leaving many of its genes still unidentified. The objective of this research was to identify gene patterns and conduct a bioinformatics analysis across various fields. The expression sequence of the betaine aldehyde dehydrogenase (BADH) gene was predicted using bioinformatics software such as PlantCARE and PlantPan. The findings indicated that different cultivars provide valuable information regarding resistance to the binding sites of MYB transcription factors, hormone response regions, and both promoter and enhancer regions, which contain 32 cis-regulatory elements. This emphasized the role of the BADH gene in responding to abiotic stress. Additionally, the research revealed that the BADH gene activates oxidoreductase activity across different cultivars, influencing NAD or NADP receptors that contribute to stress resistance. The protein lengths identified were 454 and 500 amino acids, respectively. Chloroplast analysis revealed that the GC content for the BADH gene was 37%. From this analysis, it was determined that out of 128 distinct functional genes in the genome, approximately 84 are protein-coding genes. An examination of the domains and motifs in the target genes showed that they contain two conserved sequences: Aldedh and DUF1487. Furthermore, miRNA analysis and promoter investigations indicated that the BADH gene plays a vital role in activating processes related to arginase, protein kinases, superoxide dismutase, tubulins, and membrane proteins. The gene is also crucial for activating nuclear transcription factors through receptor activation. In conclusion, the results suggest that BADH genes contribute to the plant's resistance to salt stress through various mechanisms. Stress acts as a trigger for the activation of this gene, effectively safeguarding the plant against the detrimental effects of environmental stresses.

Unveiling changes in rhizosphere-associated bacteria linked to the genotype and water stress in quinoa

Drought is among the main abiotic factors causing agronomical losses worldwide. To minimize its impact, several strategies have been proposed, including the use of plant growth-promoting bacteria (PGPBs), as they have demonstrated roles in counteracting abiotic stress. This aspect has been little explored in emergent crops such as quinoa, which has the potential to contribute to reducing food insecurity. Thus, here we hypothesize that the genotype, water environment and the type of inoculant are determining factors in shaping quinoa rhizosphere bacterial communities, affecting plant performance. To address this, two different quinoa cultivars (with contrasting water stress tolerance), two water conditions (optimal and limiting water conditions) and different soil infusions were used to define the relevance of these factors. Different bacterial families that vary among genotypes and water conditions were identified. Certain families were enriched under water stress conditions, such as the Nocardioidaceae, highly present in the water-sensitive cultivar F15, or the Pseudomonadaceae, Burkholderiaceae and Sphingomonadaceae, more abundant in the tolerant cultivar F16, which also showed larger total polyphenol content. These changes demonstrate that the genotype and environment highly contribute to shaping the root-inhabiting bacteria in quinoa, and they suggest that this plant species is a great source of PGPBs for utilization under water-liming conditions.

Shotgun proteomics of quinoa seeds reveals chitinases enrichment under rainfed conditions

Quinoa is an Andean crop whose cultivation has been extended to many different parts of the world in the last decade. It shows a great capacity for adaptation to diverse climate conditions, including environmental stressors, and, moreover, the seeds are very nutritious in part due to their high protein content, which is rich in essential amino acids. They are gluten-free seeds and contain good amounts of other nutrients such as unsaturated fatty acids, vitamins, or minerals. Also, the use of quinoa hydrolysates and peptides has been linked to numerous health benefits. Altogether, these aspects have situated quinoa as a crop able to contribute to food security worldwide. Aiming to deepen our understanding of the protein quality and function of quinoa seeds and how they can vary when this crop is subjected to water-limiting conditions, a shotgun proteomics analysis was performed to obtain the proteomes of quinoa seeds harvested from two different water regimes in the field: rainfed and irrigated conditions. Differentially increased levels of proteins determined in seeds from each field condition were analysed, and the enrichment of chitinase-related proteins in seeds harvested from rainfed conditions was found. These proteins are described as pathogen-related proteins and can be accumulated under abiotic stress. Thus, our findings suggest that chitinase-like proteins in quinoa seeds can be potential biomarkers of drought. Also, this study points to the need for further research to unveil their role in conferring tolerance when coping with water-deficient conditions.

The Disease Progression and Molecular Defense Response in Chenopodium Quinoa Infected with Peronospora Variabilis, the Causal Agent of Quinoa Downy Mildew

Downy mildew disease, caused by the biotrophic oomycete Peronospora variabilis, is the largest threat to the cultivation of quinoa (Chenopodium quinoa Willd.) in the Andean highlands, and occurs worldwide. However, so far, no molecular study of the quinoa-Peronospora interaction has been reported. Here, we developed tools to study downy mildew disease in quinoa at the gene expression level. P. variabilis was isolated and maintained, allowing the study of downy mildew disease progression in two quinoa cultivars under controlled conditions. Quinoa gene expression changes induced by P. variabilis were analyzed by qRT-PCR, for quinoa homologues of A. thaliana pathogen-associated genes. Overall, we observed a slower disease progression and higher tolerance in the quinoa cultivar Kurmi than in the cultivar Maniqueña Real. The quinoa orthologs of putative defense genes such as the catalase CqCAT2 and the endochitinase CqEP3 showed no changes in gene expression. In contrast, quinoa orthologs of other defense response genes such as the transcription factor CqWRKY33 and the chaperone CqHSP90 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.