Understanding how grapevines perceive and adapt to different environments will provide us with an insight into how to better manage crop quality. Mounting evidence suggests that epigenetic mechanisms are a key interface between the environment and the genotype that ultimately affect the plant’s phenotype. Moreover, it is now widely accepted that epigenetic mechanisms are a source of useful variability during crop varietal selection that could affect crop performance. While the contribution of DNA methylation to plant performance has been extensively studied in other major crops, very little work has been done in grapevine. To study the genetic and epigenetic diversity across 22 vineyards planted with the cultivar Shiraz in six wine sub-regions of the Barossa, South Australia Methylation Sensitive Amplified Polymorphisms (MSAP) were used to obtain global patterns of DNA methylation. The observed epigenetic profiles showed a high level of differentiation that grouped vineyards by their area of provenance despite the low genetic differentiation between vineyards and sub-regions. Pairwise epigenetic distances between vineyards indicate that the main contributor (23-24%) to the detected variability is associated to the distribution of the vineyards on the N-S axis. Analysis of the methylation profiles of vineyards pruned with the same system increased the positive correlation observed between geographic distance and epigenetic distance suggesting that pruning system affects inter-vineyard epigenetic differentiation. Finally, methylation sensitive Genotyping By Sequencing identified 3,598 differentially methylated genes in grapevine leaves that were assigned to 1,144 unique GO terms of which 8.6% were associated with response to environmental stimulus. Our results suggest that DNA methylation differences between vineyards and sub-regions within The Barossa are influenced both by the geographic location and, to a lesser extent, by pruning system. Finally, we discuss how epigenetic variability can be used as a tool to understand and potentially modulate terroir in grapevine.

RNA silencing is a eukaryotic mechanism for RNA-based gene regulation that plays an essential role in diverse biological processes, such as defence against viral infections. The P1 of rice yellow mottle virus (RYMV) is a movement protein and displays RNA silencing suppression activity with variable efficiency, depending on the origin of the isolates. In this study, the positive selection pressure acting on the P1 protein gene was assessed. A site-by-site analysis of thed_N/d_Sratio was performed and 18 positively selected sites were identified. Four of these were mutated, and the ability to suppress RNA silencing was evaluated for the resulting mutants in a transient expression assay. All mutations affected quantitatively RNA silencing suppression, one caused a significant decrease in the activity and three significantly increased it. This work demonstrates, for what is to the best of our knowledge the first time, that the RYMV gene encoding the P1 RNA silencing suppressor is under adaptive evolution.

Salinity can negatively impact crop growth and yield. Changes in DNA methylation are known to occur when plants are challenged by stress and have been associated with the regulation of stress-response genes. However, the role of DNA-methylation in moderating gene expression in response to salt stress has been relatively poorly studied among crops such as barley. Here, we assessed the extent of salt-induced alterations of DNA methylation in barley and their putative role in perturbed gene expression. Using Next Generation Sequencing, we screened the leaf and root methylomes of five divergent barley varieties grown under control and three salt concentrations, to seek genotype independent salt-induced changes in DNA methylation. Salt stress caused increased methylation in leaves but diminished methylation in roots with a higher number of changes in leaves than in roots, indicating that salt induced changes to global methylation are organ specific. Differentially Methylated Markers (DMMs) were mostly located in close proximity to repeat elements, but also in 1094 genes, of which many possessed gene ontology (GO) terms associated with plant responses to stress. Identified markers have potential value as sentinels of salt stress and provide a starting point to allow understanding of the functional role of DNA methylation in facilitating barley’s response to this stressor.

In Burkina Faso, dietary patterns lack diversification and is characterized by a low consumption of vegetables. This is attributable to rooted eating habits, limited accessibility to vegetables, and a lack of awareness regarding the positive health effects and overall well-being associated with vegetable consumption. Raising consumers’ awareness about the benefits of high intake of vegetables such as tomatoes can boost vegetable demand and supply. This review aims to highlight the nutritional characteristics and health benefits of tomato consumption, as well as its socio-economic importance for the population, especially women and youth. The literature revealed that tomato is recognized as a good source of carbohydrates, proteins, fatty acids, minerals, vitamins, amino acids and phenolic compounds and has therapeutic properties that can treat diarrhea and hypertension. A number of studies have reported that tomato’s consumption help reduce the risk of cardiovascular disease, cancer and diabetes. Furthermore, tomato cultivation generates substantial income for producers and so reduces seasonal unemployment and poverty in many regions. Additionally, tomato cultivation can contribute to the resilience of populations to tackle the effects of climate change by enhancing food and nutritional security.

Groundnut (Arachis hypogaea L.) is a major food and cash crop in Burkina Faso. Due to the growing demand for raw oilseeds, there is an increasing interest in groundnut production from traditional rain-fed areas to irrigated environments. However, despite implementation of many initiatives in the past to increase groundnut productivity and production, the groundnut industry still struggles to prosper due to the fact of several constraints including minimal development research and fluctuating markets. Yield penalty due to the presence of drought and biotic stresses continue to be a major drawback for groundnut production. This review traces progress in the groundnut breeding that started in Burkina Faso before the country’s political independence in 1960 through to present times. Up to the 1980s, groundnut improvement was led by international research institutions such as IRHO (Institute of Oils and Oleaginous Research) and ICRISAT (International Crops Research Institute for the Semi-Arid Tropics). However, international breeding initiatives were not sufficient to establish a robust domestic groundnut breeding programme. This review also provides essential information about opportunities and challenges for groundnut research in Burkina Faso, emphasising the need for institutional attention to genetic improvement of the crop.